aspirin/omeprazole (Rx)

Prevention of Cardiovascular and Cerebrovascular Events

Indicated for patients requiring aspirin for secondary prevention of cardiovascular and cerebrovascular events who are at risk of developing aspirin-associated gastric ulcers

1 tablet PO qDay (available in combinations that contain aspirin 81 mg or 325 mg)

Cardiovascular secondary prevention: Generally 81 mg of aspirin has been accepted as an effective dose for secondary cardiovascular prevention

Consider the need for the 325-mg combination as recommended by current clinical practice guidelines

Also see Administration

Dosage Modifications

Renal impairment

• Mild-to-moderate: No dose reduction required
• Severe (GFR <10 mL/min): Avoid use owing to the aspirin component (also see Cautions)

Hepatic impairment

• Avoid use with any degree of hepatic impairment
• Hepatic impairment increases omeprazole systemic exposure

Dosing Considerations

Limitations of use

• Aspirin component is delayed release; not for use as the initial dose of aspirin therapy during onset of acute coronary syndrome, during acute myocardial infarction, or before percutaneous coronary intervention (PCI)
• The combination has not been shown to reduce the risk of gastrointestinal bleeding due to aspirin
• Not interchangeable with the individual components of aspirin and omeprazole

Safety and efficacy not established

Contraindicated (7)

• abrocitinib

  abrocitinib and aspirin both increase anticoagulation. Contraindicated. Antiplatelet drugs, except for low-dose aspirin (=81 mg qDay), during the first 3 months of treatment are contraindicated.

• dichlorphenamide

  dichlorphenamide increases levels of aspirin by unknown mechanism. Contraindicated. Coadministration of dichlorphenamide with high-dose aspirin may increase salicylate levels. Anorexia, tachypnea, lethargy, and coma reported.

• erlotinib

  omeprazole decreases levels of erlotinib by Other (see comment). Contraindicated. Comment: Concomitant use of proton pump inhibitors with erlotinib should be avoided if possible. Drugs that alter pH of upper GI tract may alter the solubility of erlotinib and reduce its bioavailability. .

• fezolinetant

  omeprazole will increase the level or effect of fezolinetant by affecting hepatic enzyme CYP1A2 metabolism. Contraindicated. Fezolinetant AUC and peak plasma concentration are increased if coadministered with drugs that are weak, moderate, or strong CYP1A2 inhibitors

• mavacamten

  omeprazole will increase the level or effect of mavacamten by affecting hepatic enzyme CYP2C19 metabolism. Contraindicated. Strong or moderate CYP2C19 inhibitors may increase mavacamten systemic exposure, resulting in heart failure due to systolic dysfunction.

• mifepristone

  aspirin, mifepristone. Other (see comment). Contraindicated. Comment: Aspirin induced antiplatelet activity may induce excessive bleeding after an abortion w/mifepristone (RU 486).

• nelfinavir

  omeprazole decreases levels of nelfinavir by unspecified interaction mechanism. Contraindicated. Coadministration may lead to loss of nelfinavir virologic response and development of resistance; mechanism may be CYP2C19 inhibition of nelfinavir conversion to active M8 metabolite, and also PPIs decreasing gastric pH resulting in decreased nelfinavir absorption.

Serious - Use Alternative (69)

• abametapir

  abametapir will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For 2 weeks after abametapir application, avoid taking drugs that are CYP3A4 substrates. If not feasible, avoid use of abametapir.

• abrocitinib

  omeprazole will increase the level or effect of abrocitinib by decreasing metabolism. Avoid or Use Alternate Drug. Abrocitinib is a CYP2C9 and CYP2C19 substrate. Drugs that are moderate-to-strong inhibitors of both CYP2C9 and CYP2C19 increase systemic exposure of abrocitinib and its active metabolites, which may increase adverse effects.

• acalabrutinib

  omeprazole decreases levels of acalabrutinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Acalabrutinib solubility decreases with increasing gastric pH. Due to the long-lasting effect of PPIs, separation of doses may not eliminate the interaction.

• apalutamide

  apalutamide will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug. Coadministration of apalutamide, a strong CYP2C19 inducer, with drugs that are CYP2C19 substrates can result in lower exposure to these medications. Avoid or substitute another drug for these medications when possible. Evaluate for loss of therapeutic effect if medication must be coadministered.
  
  apalutamide will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of apalutamide, a strong CYP3A4 inducer, with drugs that are CYP3A4 substrates can result in lower exposure to these medications. Avoid or substitute another drug for these medications when possible. Evaluate for loss of therapeutic effect if medication must be coadministered. Adjust dose according to prescribing information if needed.

• atazanavir

  omeprazole will decrease the level or effect of atazanavir by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Atazanavir solubility decreases as pH increases. Substantially reduced plasma concentrations of atazanavir are expected if PPIs are coadministered. PPI dose should not exceed a dose comparable to omeprazole 20 mg and must be taken ~12 h before atazanavir/ritonavir in treatment naive-patients. PPIs are not recommended in treatment-experienced taking atazanavir.

• benazepril

  aspirin, benazepril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• caplacizumab

  caplacizumab, aspirin. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug.

• captopril

  aspirin, captopril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• carbamazepine

  carbamazepine will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

• ceritinib

  omeprazole decreases effects of ceritinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• cilostazol

  omeprazole will increase the level or effect of cilostazol by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

• clopidogrel

  omeprazole decreases effects of clopidogrel by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug. Clopidogrel efficacy may be reduced by drugs that inhibit CYP2C19. Inhibition of platelet aggregation by clopidogrel is entirely due to an active metabolite. Clopidogrel is metabolized to this active metabolite in part by CYP2C19. .

• dacomitinib

  omeprazole will increase the level or effect of dacomitinib by unspecified interaction mechanism. Avoid or Use Alternate Drug. Concomitant use with a PPI decreases dacomitinib concentrations, which may reduce dacomitinib efficacy. Avoid use of PPIs with dacomitinib. As an alternative to PPIs, use locally-acting antacids or an H2-receptor antagonist. Administer at least 6 hours before or 10 hours after taking an H2-receptor antagonist.

• dasatinib

  omeprazole will decrease the level or effect of dasatinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• digoxin

  omeprazole will increase the level or effect of digoxin by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• duloxetine

  omeprazole will decrease the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

• enalapril

  aspirin, enalapril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• enzalutamide

  enzalutamide will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• erdafitinib

  omeprazole will increase the level or effect of erdafitinib by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug. If coadministration of a strong CYP2C9 inhibitors is unavoidable, closely monitor adverse reactions and modify dose of erdafitinib accordingly. If strong CYP2C9 inhibitor is discontinued, consider increasing erdafitinib dose in the absence of any drug-related toxicities.

• fedratinib

  omeprazole will increase the level or effect of fedratinib by Other (see comment). Avoid or Use Alternate Drug. Avoid coadministration of fedratinib (a CYP3A4 and CYP2C19 substrate) with dual CYP3A4 and CYP2C19 inhibitor. Effect of coadministration of a dual CYP3A4 and CYP2C19 inhibitor with fedratinib has not been studied.

• fexinidazole

  fexinidazole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Fexinidazole inhibits CYP3A4. Coadministration may increase risk for adverse effects of CYP3A4 substrates.

• fluvoxamine

  fluvoxamine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

• fosinopril

  aspirin, fosinopril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• ibuprofen

  ibuprofen decreases effects of aspirin by Other (see comment). Avoid or Use Alternate Drug. Comment: Ibuprofen decreases the antiplatelet effects of low-dose aspirin by blocking the active site of platelet cyclooxygenase. Administer ibuprofen 8 h before aspirin or at least 2-4 h after aspirin. The effect of other NSAIDs on aspirin is not established.
  
  ibuprofen increases toxicity of aspirin by anticoagulation. Avoid or Use Alternate Drug. increases risk of bleeding.

• ibuprofen IV

  ibuprofen IV increases toxicity of aspirin by anticoagulation. Avoid or Use Alternate Drug. increases risk of bleeding.
  
  ibuprofen IV decreases effects of aspirin by Other (see comment). Avoid or Use Alternate Drug. Comment: Ibuprofen decreases the antiplatelet effects of low-dose aspirin by blocking the active site of platelet cyclooxygenase. Administer ibuprofen 8 h before aspirin or at least 2-4 h after aspirin. The effect of other NSAIDs on aspirin is not established.

• idelalisib

  idelalisib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Idelalisib is a strong CYP3A inhibitor; avoid coadministration with sensitive CYP3A substrates

• indinavir

  omeprazole will decrease the level or effect of indinavir by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• infigratinib

  omeprazole will decrease the level or effect of infigratinib by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• isoniazid

  isoniazid will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

• itraconazole

  omeprazole will decrease the level or effect of itraconazole by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• ivosidenib

  ivosidenib will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternative therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs.

• ketoconazole

  omeprazole will decrease the level or effect of ketoconazole by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• ketorolac

  aspirin, ketorolac. Either increases toxicity of the other by pharmacodynamic synergism. Contraindicated.

• ketorolac intranasal

  aspirin, ketorolac intranasal. Either increases toxicity of the other by pharmacodynamic synergism. Contraindicated.

• lesinurad

  aspirin decreases effects of lesinurad by unspecified interaction mechanism. Avoid or Use Alternate Drug. Aspirin at doses >325 mg/day may decrease lesinurad efficacy. Aspirin doses 325 mg/day or less (ie, for cardiovascular event prophylaxis) does not decrease lesinurad efficacy and can be coadministered.

• levoketoconazole

  omeprazole will decrease the level or effect of levoketoconazole by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• lisinopril

  aspirin, lisinopril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• lonafarnib

  omeprazole will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of lonafarnib (a sensitive CYP3A substrate) with weak CYP3A inhibitors is unavoidable, reduce to, or continue lonafarnib at starting dose. Closely monitor for arrhythmias and events (eg, syncope, heart palpitations) since lonafarnib effect on QT interval is unknown.
  
  lonafarnib will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug. Lonafarnib may increase the AUC and peak concentration of CYP2C19 substrates. If coadministration unavoidable, monitor for adverse reactions and reduce the CYP2C19 substrate dose in accordance with its approved product labeling.

• macimorelin

  aspirin, macimorelin. unspecified interaction mechanism. Avoid or Use Alternate Drug. Drugs that directly affect the pituitary secretion of growth hormone (GH) may impact the accuracy of the macimorelin diagnostic test. Allow sufficient washout time of drugs affecting GH release before administering macimorelin. .

• measles, mumps, rubella and varicella vaccine, live

  aspirin, measles, mumps, rubella and varicella vaccine, live. Mechanism: unspecified interaction mechanism. Avoid or Use Alternate Drug. Risk of Reye's Syndrome with combination; avoid salicylate use for 6 wks after vaccination.

• mesalamine

  omeprazole decreases effects of mesalamine by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Applies only to sustained release dosage form.

• methotrexate

  aspirin increases levels of methotrexate by decreasing renal clearance. Avoid or Use Alternate Drug. Caution should be exercised when salicylates are given in combination with methotrexate. Risk for drug interactions with methotrexate is greatest during high-dose methotrexate therapy, it has been recommended that any of these drugs be used cautiously with methotrexate even when methotrexate is used in low doses.

• mifepristone

  aspirin will decrease the level or effect of mifepristone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• mitotane

  aspirin will decrease the level or effect of mitotane by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• moexipril

  aspirin, moexipril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• neratinib

  omeprazole will decrease the level or effect of neratinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• nilotinib

  omeprazole will decrease the level or effect of nilotinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Nilotinib has a pH-dependent solubility and solubility is decreased at higher pH; separating doses may not eliminate this effect because of PPI extended duration of action

• nisoldipine

  omeprazole will increase the level or effect of nisoldipine by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• pazopanib

  omeprazole will decrease the level or effect of pazopanib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Avoid coadministration of pazopanib with drugs that raise gastric pH; consider short-acting antacids in place of PPIs and H2 antagonists; separate antacid and pazopanib dosing by several hours

• pemetrexed

  aspirin increases levels of pemetrexed by unspecified interaction mechanism. Avoid or Use Alternate Drug. Interrupt dosing in all patients taking NSAIDs with long elimination half-lives for at least 5d before, the day of, and 2d following pemetrexed administration. If coadministration of an NSAID is necessary, closely monitor patients for toxicity, especially myelosuppression, renal toxicity, and GI toxicity.

• perindopril

  aspirin, perindopril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• pexidartinib

  omeprazole will decrease the level or effect of pexidartinib by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Avoid coadministration of proton pump inhibitors (PPIs) with pexidartinib. Use H2-receptor antagonists or antacids if needed. When using alternatives to PPIs, administer pexidartinib 2 hr before or after taking locally-acting antacids OR administer pexidartinib at least 2 hr before or 10 hr after taking an H2-receptor antagonist.

• phenobarbital

  phenobarbital will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• probenecid

  aspirin decreases effects of probenecid by acidic (anionic) drug competition for renal tubular clearance. Avoid or Use Alternate Drug. Aspirin decreases uricosuric action of probenecid.

• quinapril

  aspirin, quinapril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• ramipril

  aspirin, ramipril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• rifampin

  rifampin will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• rifapentine

  rifapentine will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• secobarbital

  secobarbital will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• secretin

  omeprazole, secretin. Other (see comment). Avoid or Use Alternate Drug. Comment: Concomitant use of PPIs may cause a hyperresponse in gastrin secretion in response to stimulation testing with secretin, falsely suggesting gastrinoma. The time it takes for serum gastrin concentrations to return to baseline following discontinuation of PPIs is specific to the individual PPI. Temporarily stop omeprazole treatment at least 14 days before assessing to allow gastrin levels to return to baseline.

• siponimod

  omeprazole will increase the level or effect of siponimod by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with drugs that cause moderate CYP2C9 AND a moderate or strong CYP3A4 inhibition is not recommended. Caution if siponimod coadministered with moderate CYP2C9 inhibitors alone.

• sofosbuvir/velpatasvir

  omeprazole will decrease the level or effect of sofosbuvir/velpatasvir by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Velpatasvir solubility decreases as gastric pH increases (practically insoluble at pH >5). Coadministration of sofosbuvir/velpatasvir with omeprazole or other PPIs is not recommended. If considered medically necessary, give sofosbuvir/velpatasvir with food 4 hr before omeprazole 20 mg. Use with other PPIs has not been studied.

• sotorasib

  omeprazole will decrease the level or effect of sotorasib by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug. If use with an acid-reducing agent cannot be avoided, administer sotorasib 4 hr before or 10 hr after administration of a locally-acting antacid.

• sparsentan

  omeprazole decreases effects of sparsentan by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Proton pump inhibitors may decrease sparsentan exposure which may reduce efficacy of sparsentan.

• ticlopidine

  aspirin increases effects of ticlopidine by pharmacodynamic synergism. Avoid or Use Alternate Drug. Enhanced risk of hemorrhage.

• trandolapril

  aspirin, trandolapril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• tucatinib

  tucatinib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.

• varicella virus vaccine live

  aspirin, varicella virus vaccine live. Mechanism: unspecified interaction mechanism. Avoid or Use Alternate Drug. Risk of Reye's Syndrome with combination; avoid salicylate use for 6 wks after vaccination.

• voxelotor

  voxelotor will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.

Monitor Closely (357)

• abciximab

  aspirin, abciximab. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• abrocitinib

  omeprazole will increase the level or effect of abrocitinib by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Start abrocitinib 50 mg qDay when coadministered with CYP2C19 inhibitors. If adequate response not achieved after 12 weeks, may increase to 100 mg qDay. Discontinue if inadequate response after dosage increase.

• acalabrutinib

  acalabrutinib increases effects of aspirin by anticoagulation. Modify Therapy/Monitor Closely. Coadministration of acalabrutinib with antiplatelets or anticoagulants may further increase risk of hemorrhage. Monitor for signs of bleeding and consider the benefit-risk of withholding acalabrutinib for 3-7 days presurgery and postsurgery depending upon the type of surgery and the risk of bleeding.

• acebutolol

  acebutolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of acebutolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• aceclofenac

  aceclofenac and aspirin both increase anticoagulation. Use Caution/Monitor.
  
  aceclofenac and aspirin both increase serum potassium. Use Caution/Monitor.

• acemetacin

  acemetacin and aspirin both increase anticoagulation. Use Caution/Monitor.
  
  acemetacin and aspirin both increase serum potassium. Use Caution/Monitor.

• acetazolamide

  acetazolamide, aspirin. Either increases levels of the other by Other (see comment). Use Caution/Monitor. Comment: Carbonic anhydrase inhibitors (CAIs) and salicylates inhibit each other's renal tubular secretion, resulting in increased plasma levels. CAIs also shift salicylates from plasma to the CNS, leading to potential neurotoxicity.
  
  acetazolamide, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Use Caution/Monitor. Salicylate levels increased at moderate doses; risk of CNS toxicity. Salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• agrimony

  aspirin and agrimony both increase anticoagulation. Use Caution/Monitor.

• albuterol

  aspirin increases and albuterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• alfalfa

  aspirin and alfalfa both increase anticoagulation. Use Caution/Monitor.

• alfuzosin

  aspirin decreases effects of alfuzosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• aliskiren

  aspirin will decrease the level or effect of aliskiren by Other (see comment). Use Caution/Monitor. In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, coadministration of NSAIDs with drugs that affect RAAS may increase the risk of renal impairment (including acute renal failure) and cause loss of antihypertensive effect. Monitor renal function periodically.

• alteplase

  aspirin, alteplase. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• American ginseng

  aspirin and American ginseng both increase anticoagulation. Use Caution/Monitor.

• amiloride

  amiloride and aspirin both increase serum potassium. Modify Therapy/Monitor Closely.

• amobarbital

  amobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• amoxicillin

  amoxicillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  amoxicillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• ampicillin

  omeprazole will decrease the level or effect of ampicillin by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.
  
  ampicillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.

• anagrelide

  aspirin, anagrelide. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; increases risk of bleeding; monitor closely.
  
  anagrelide, aspirin. Either increases toxicity of the other by Mechanism: pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; increases risk of bleeding; monitor closely.

• armodafinil

  armodafinil will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• antithrombin alfa

  antithrombin alfa and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.
  
  aspirin, antithrombin alfa. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• antithrombin III

  antithrombin III and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.
  
  aspirin, antithrombin III. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• apixaban

  aspirin and apixaban both increase anticoagulation. Modify Therapy/Monitor Closely. Both drugs have the potential to cause bleeding. The need for simultaneous use of low-dose aspirin (<100 mg/day) with anticoagulants are common for patients with cardiovascular disease, but may result in increased bleeding; monitor closely. Promptly evaluate any signs or symptoms of blood loss if treated concomitantly with low-dose aspiriin. Avoid coadministration with chronic use of higher dose aspirin. In 1 trial (APPRAISE-2), therapy was terminated because of significantly increased bleeding when apixaban was administered with dual antiplatelet therapy (eg, aspirin plus clopidogrel) compared with single antiplatelet treatment

• arformoterol

  aspirin increases and arformoterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• argatroban

  argatroban and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.
  
  aspirin, argatroban. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• asenapine

  aspirin decreases effects of asenapine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• atenolol

  atenolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of atenolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• avapritinib

  omeprazole will increase the level or effect of avapritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• axitinib

  omeprazole increases levels of axitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• azficel-T

  azficel-T, aspirin. Other (see comment). Use Caution/Monitor. Comment: Patients taking aspirin may experience increased bruising or bleeding at biopsy and/or injection sites. Concomitant use of aspirin is not recommended. .

• azilsartan

  aspirin, azilsartan. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of azilsartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.

• belumosudil

  omeprazole will decrease the level or effect of belumosudil by increasing gastric pH. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Increase belumosudil dosage to 200 mg PO BID when coadministered with proton pump inhibitors.

• belzutifan

  omeprazole will increase the level or effect of belzutifan by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Belzutifan is a CYP2C19 substrate. Coadministration with CYP2C19 inhibitors may increase incidence or severity of adverse effects. Monitor for anemia and hypoxia and reduce belzutifan dose as recommended.

• bemiparin

  bemiparin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• benazepril

  benazepril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.

• bendamustine

  omeprazole decreases levels of bendamustine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Concentrations of active metabolites may be increased.

• bendroflumethiazide

  aspirin increases and bendroflumethiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• betaxolol

  betaxolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of betaxolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• betrixaban

  aspirin, betrixaban. Either increases levels of the other by anticoagulation. Use Caution/Monitor.

• bimatoprost

  bimatoprost, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• bisoprolol

  bisoprolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of bisoprolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• bivalirudin

  bivalirudin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.
  
  aspirin, bivalirudin. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• bortezomib

  bortezomib will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• bosutinib

  omeprazole decreases levels of bosutinib by Other (see comment). Use Caution/Monitor. Comment: PPIs may decrease bosutinib concentration by ~45%; bosutinib displays pH-dependent solubility.

• brinzolamide

  brinzolamide, aspirin. Either increases levels of the other by Other (see comment). Use Caution/Monitor. Comment: Carbonic anhydrase inhibitors (CAIs) and salicylates inhibit each other's renal tubular secretion, resulting in increased plasma levels. CAIs also shift salicylates from plasma to the CNS, leading to potential neurotoxicity.

• budesonide

  omeprazole decreases effects of budesonide by increasing gastric pH. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Enteric-coated budesonide dissolves at pH >5.5. Also, dissolution of extended-release budesonide tablets is pH dependent. Coadministration with drugs that increase gastric pH may cause these budesonide products to prematurely dissolve, and possibly affect release properties and absorption of the drug in the duodenum.

• bumetanide

  aspirin increases and bumetanide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  aspirin decreases effects of bumetanide by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• butabarbital

  butabarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• butalbital

  butalbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• candesartan

  candesartan and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of candesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  candesartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.

• cannabidiol

  omeprazole will increase the level or effect of cannabidiol by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider reducing the cannabidiol dose when coadministered with a strong CYP2C19 inhibitor.
  
  cannabidiol will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider reducing the dose of sensitive CYP2C19 substrates, as clinically appropriate, when coadministered with cannabidiol.

• capecitabine

  omeprazole decreases effects of capecitabine by unknown mechanism. Use Caution/Monitor. Retrospective data suggest elevated gastric pH caused by PPI use may impair capecitabine tablet dissolution and/or reduce absorption.

• captopril

  captopril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, elderly or volume depleted individuals.

• carbamazepine

  carbamazepine will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• carbenoxolone

  aspirin increases and carbenoxolone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• carbonyl iron

  omeprazole will decrease the level or effect of carbonyl iron by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• carvedilol

  carvedilol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of carvedilol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• cefpodoxime

  omeprazole decreases effects of cefpodoxime by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• cefuroxime

  omeprazole decreases effects of cefuroxime by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• celecoxib

  aspirin and celecoxib both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and celecoxib both increase serum potassium. Use Caution/Monitor.

• celiprolol

  celiprolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of celiprolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• cenobamate

  cenobamate will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.
  
  cenobamate will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider a dose reduction of CYP2C19 substrates, as clinically appropriate, when used concomitantly with cenobamate.

• chlorothiazide

  aspirin increases and chlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• chlorpropamide

  aspirin increases effects of chlorpropamide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.

• chlorthalidone

  aspirin increases and chlorthalidone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• choline magnesium trisalicylate

  aspirin and choline magnesium trisalicylate both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and choline magnesium trisalicylate both increase serum potassium. Use Caution/Monitor.

• cilostazol

  aspirin, cilostazol. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• cinnamon

  aspirin and cinnamon both increase anticoagulation. Use Caution/Monitor.

• ciprofloxacin

  aspirin decreases levels of ciprofloxacin by Other (see comment). Use Caution/Monitor. Comment: Buffered aspirin may decrease absorption of quinolones. Consider administering 2 hr before or 6 hr after, buffered aspirin administration.
  
  omeprazole will decrease the level or effect of ciprofloxacin by unknown mechanism. Use Caution/Monitor. Absorption of the ciprofloxacin ER tablet was slightly diminished (20%) when coadministered with omeprazole.

• citalopram

  omeprazole will increase the level or effect of citalopram by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Citalopram 20 mg/day is the maximum recommended dose for patients taking CYP2C19 inhibitors because of the risk of QT prolongation.
  
  citalopram, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. If possible, avoid concurrent use.

• clobazam

  omeprazole will increase the level or effect of clobazam by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Dosage adjustment may be required; CYP2C19 inhibitors may result in increased exposure to N-desmethylclobazam (active metabolite).

• clomipramine

  clomipramine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. Clomipramine inhib. serotonin uptake by platelets.

• clopidogrel

  aspirin, clopidogrel. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• clozapine

  omeprazole will decrease the level or effect of clozapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

• cobicistat

  cobicistat will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• collagenase clostridium histolyticum

  aspirin increases toxicity of collagenase clostridium histolyticum by anticoagulation. Use Caution/Monitor. Collagenase clostridium histolyticum has high incidence of ecchymosis/contusion at injection site; avoid concomitant anticoagulants (except for low-dose aspirin, ie, up to 150 mg/day).

• conivaptan

  conivaptan will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cordyceps

  aspirin and cordyceps both increase anticoagulation. Use Caution/Monitor.

• cortisone

  aspirin, cortisone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.

• crizotinib

  omeprazole will decrease the level or effect of crizotinib by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor. Drugs that elevate the gastric pH may decrease the solubility of crizotinib and subsequently reduce its bioavailability. However, no formal studies have been conducted.

• cyclopenthiazide

  aspirin increases and cyclopenthiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• cyclosporine

  omeprazole, cyclosporine. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Long-term use of PPIs may cause hypomagnesemia and increase this risk when coadministered with drugs that may also decrease magnesium levels.

• dabigatran

  dabigatran and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely. Both drugs have the potential to cause bleeding. The need for simultaneous use of low-dose aspirin (<100 mg/day) with anticoagulants are common for patients with cardiovascular disease, but may result in increased bleeding; monitor closely. Promptly evaluate any signs or symptoms of blood loss if treated concomitantly with low-dose aspirin. Avoid coadministration with chronic use of higher dose aspirin

• dabrafenib

  omeprazole will decrease the level or effect of dabrafenib by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor. Drugs that alter upper GI tract pH (eg, PPIs, H2-blockers, antacids) may decrease dabrafenib solubility and reduce its bioavailability
  
  dabrafenib will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Use alternative if available

• dalteparin

  dalteparin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.
  
  aspirin, dalteparin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• deferasirox

  deferasirox, aspirin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase GI bleeding, ulceration and irritation. Use with caution.

• defibrotide

  defibrotide increases effects of aspirin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Defibrotide may enhance effects of platelet inhibitors.

• deflazacort

  aspirin, deflazacort. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.

• desirudin

  aspirin, desirudin. Either increases levels of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• dexamethasone

  aspirin, dexamethasone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.

• dextroamphetamine

  omeprazole, dextroamphetamine. Other (see comment). Use Caution/Monitor. Comment: Reduced gastric acidity caused by proton pump inhibitors decreases time to Tmax for amphetamine and dextroamphetamine. AUC was unaffected. .

• diazepam intranasal

  omeprazole will increase the level or effect of diazepam intranasal by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Strong or moderate CYP2C19 inhibitors may decrease rate of diazepam elimination, thereby increasing adverse reactions to diazepam.

• dichlorphenamide

  dichlorphenamide and omeprazole both decrease serum potassium. Use Caution/Monitor.

• diclofenac

  aspirin and diclofenac both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and diclofenac both increase serum potassium. Use Caution/Monitor.

• dicloxacillin

  dicloxacillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.

• diflunisal

  aspirin and diflunisal both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and diflunisal both increase serum potassium. Use Caution/Monitor.

• digoxin

  aspirin and digoxin both increase serum potassium. Use Caution/Monitor.
  
  omeprazole increases toxicity of digoxin by Other (see comment). Use Caution/Monitor. Comment: Prolonged use of PPIs may cause hypomagnesemia and increase risk for digoxin toxicity.

• dipyridamole

  aspirin, dipyridamole. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• efavirenz

  efavirenz will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  efavirenz will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• dobutamine

  aspirin increases and dobutamine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dong quai

  aspirin and dong quai both increase anticoagulation. Use Caution/Monitor.

• dopexamine

  aspirin increases and dopexamine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• doxazosin

  aspirin decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• drospirenone

  drospirenone and aspirin both increase serum potassium. Modify Therapy/Monitor Closely.

• duloxetine

  duloxetine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• edoxaban

  edoxaban, aspirin. Either increases toxicity of the other by anticoagulation. Modify Therapy/Monitor Closely. Both drugs have the potential to cause bleeding. The need for simultaneous use of low-dose aspirin (<100 mg/day) with anticoagulants are common for patients with cardiovascular disease, but may result in increased bleeding; monitor closely. Promptly evaluate any signs or symptoms of blood loss if treated concomitantly with low-dose aspirin. Avoid coadministration with chronic use of higher dose aspirin.

• elagolix

  elagolix will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak inhibitor of CYP2C19. No dose adjustments are needed for omeprazole with 40 mg/day or less. Consider omeprazole dose reduction with higher omeprazole doses (eg, dose for Zollinger-Ellison) if coadministered with elagolix.
  
  elagolix decreases levels of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.

• eltrombopag

  omeprazole will decrease the level or effect of eltrombopag by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

• eluxadoline

  omeprazole increases levels of eluxadoline by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. As a precautionary measure due to incomplete information on the metabolism of eluxadoline, use caution when coadministered with strong CYP2C19 inhibitors.

• elvitegravir/cobicistat/emtricitabine/tenofovir DF

  elvitegravir/cobicistat/emtricitabine/tenofovir DF, aspirin. Either increases toxicity of the other by decreasing renal clearance. Modify Therapy/Monitor Closely. Toxicity may result from coadministration of emtricitabine and tenofovir with other drugs that are also primarily excreted by glomerular filtration and/or active tubular secretion including high-dose or multiple-dose NSAIDs; alternatives to NSAIDs should be considered.

• enalapril

  enalapril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.

• encorafenib

  encorafenib, omeprazole. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Encorafenib both inhibits and induces CYP3A4 at clinically relevant plasma concentrations. Coadministration of encorafenib with sensitive CYP3A4 substrates may result in increased toxicity or decreased efficacy of these agents.

• enoxaparin

  enoxaparin and aspirin both increase anticoagulation. Use Caution/Monitor. Additive effects are intended when both drugs are prescribed as indicated for unstable angina, non-Q-wave MI, and STEMI
  
  aspirin, enoxaparin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• ephedrine

  aspirin increases and ephedrine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epinephrine

  aspirin increases and epinephrine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epinephrine racemic

  aspirin increases and epinephrine racemic decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epoprostenol

  aspirin and epoprostenol both increase anticoagulation. Use Caution/Monitor.

• eprosartan

  eprosartan and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of eprosartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  eprosartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.

• eptifibatide

  aspirin, eptifibatide. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• escitalopram

  omeprazole will increase the level or effect of escitalopram by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  escitalopram, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• eslicarbazepine acetate

  eslicarbazepine acetate will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• esmolol

  esmolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of esmolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• ethacrynic acid

  aspirin increases and ethacrynic acid decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• etodolac

  aspirin and etodolac both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and etodolac both increase serum potassium. Use Caution/Monitor.

• etravirine

  etravirine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• fedratinib

  fedratinib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.

• fenbufen

  aspirin and fenbufen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and fenbufen both increase serum potassium. Use Caution/Monitor.

• fennel

  aspirin and fennel both increase anticoagulation. Use Caution/Monitor.

• fenoprofen

  aspirin and fenoprofen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and fenoprofen both increase serum potassium. Use Caution/Monitor.

• ferric gluconate

  omeprazole will decrease the level or effect of ferric gluconate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ferric maltol

  omeprazole will decrease the level or effect of ferric maltol by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ferrous fumarate

  omeprazole will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ferrous gluconate

  omeprazole will decrease the level or effect of ferrous gluconate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ferrous sulfate

  omeprazole will decrease the level or effect of ferrous sulfate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• feverfew

  aspirin and feverfew both increase anticoagulation. Use Caution/Monitor.

• fexinidazole

  fexinidazole will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• finerenone

  omeprazole will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or weak CYP3A4 inhibitors. Adjust finererone dosage as needed.

• fish oil

  fish oil, aspirin. Other (see comment). Use Caution/Monitor. Comment: Patients taking fish oil and an anticoagulant or other drug affecting coagulation should be monitored periodically due to potential increased risk of bleeding. .

• fish oil triglycerides

  fish oil triglycerides will increase the level or effect of aspirin by anticoagulation. Use Caution/Monitor. Prolonged bleeding reported in patients taking antiplatelet agents or anticoagulants and oral omega-3 fatty acids. Periodically monitor bleeding time in patients receiving fish oil triglycerides and concomitant antiplatelet agents or anticoagulants.

• flibanserin

  omeprazole will increase the level or effect of flibanserin by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Coadministration of flibanserin with strong CYP2C19 inhibitors may increase flibanserin exposure and increase the risk of hypotension, syncope, and CNS depression.
  
  omeprazole will increase the level or effect of flibanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Increased flibanserin adverse effects may occur if coadministered with multiple weak CYP3A4 inhibitors.

• fluconazole

  fluconazole will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• fludrocortisone

  aspirin, fludrocortisone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.

• fluoxetine

  fluoxetine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• flurbiprofen

  aspirin and flurbiprofen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and flurbiprofen both increase serum potassium. Use Caution/Monitor.

• fluvoxamine

  fluvoxamine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding SSRIs inhib. serotonin uptake by platelets.

• fondaparinux

  fondaparinux and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• formoterol

  aspirin increases and formoterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• forskolin

  aspirin and forskolin both increase anticoagulation. Use Caution/Monitor.

• fosamprenavir

  omeprazole will decrease the level or effect of fosamprenavir by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• fosinopril

  fosinopril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.

• fosphenytoin

  omeprazole will increase the level or effect of fosphenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  fosphenytoin will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• furosemide

  aspirin increases and furosemide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• garlic

  aspirin and garlic both increase anticoagulation. Use Caution/Monitor.

• gefitinib

  omeprazole decreases levels of gefitinib by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor. Avoid coadministration of gefitinib with PPIs if possible. If treatment with a PPI is required, separate gefitinib and PPI doses by 12 hr.

• gentamicin

  aspirin increases and gentamicin decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• ginger

  aspirin and ginger both increase anticoagulation. Use Caution/Monitor.

• ginkgo biloba

  aspirin and ginkgo biloba both increase anticoagulation. Use Caution/Monitor.

• glimepiride

  aspirin increases effects of glimepiride by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.

• glipizide

  aspirin increases effects of glipizide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.

• glyburide

  omeprazole will increase the level or effect of glyburide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  aspirin increases effects of glyburide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.

• green tea

  green tea increases effects of aspirin by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical, due to caffeine content). Combination may increase risk of bleeding.

• iloperidone

  iloperidone increases levels of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Iloperidone is a time-dependent CYP3A inhibitor and may lead to increased plasma levels of drugs predominantly eliminated by CYP3A4.

• griseofulvin

  griseofulvin decreases levels of aspirin by unknown mechanism. Use Caution/Monitor.

• heparin

  heparin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.
  
  aspirin, heparin. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• horse chestnut seed

  aspirin and horse chestnut seed both increase anticoagulation. Use Caution/Monitor.

• hyaluronidase

  aspirin decreases effects of hyaluronidase by Other (see comment). Use Caution/Monitor. Comment: Salicylates, when given in large systemic doses, may render tissues partially resistant to the action of hyaluronidase. Patients may require larger amounts of hyaluronidase for equivalent dispersing effect.

• hydralazine

  aspirin decreases effects of hydralazine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• hydrochlorothiazide

  aspirin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• hydrocortisone

  aspirin, hydrocortisone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.

• ibrutinib

  ibrutinib will increase the level or effect of aspirin by anticoagulation. Use Caution/Monitor. Ibrutinib may increase the risk of hemorrhage in patients receiving antiplatelet or anticoagulant therapies and monitor for signs of bleeding.

• ibuprofen

  aspirin and ibuprofen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and ibuprofen both increase serum potassium. Use Caution/Monitor.

• ibuprofen IV

  aspirin will increase the level or effect of ibuprofen IV by acidic (anionic) drug competition for renal tubular clearance. Modify Therapy/Monitor Closely.
  
  aspirin and ibuprofen IV both increase anticoagulation. Modify Therapy/Monitor Closely.
  
  aspirin and ibuprofen IV both increase serum potassium. Use Caution/Monitor.

• icosapent

  icosapent, aspirin. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Icosapent may prolong bleeding time; monitor periodically if coadministered with other drugs that affect bleeding.

• imatinib

  imatinib, aspirin. Either increases toxicity of the other by Other (see comment). Modify Therapy/Monitor Closely. Comment: Imatinib may cause thrombocytopenia; bleeding risk increased when imatinib is coadministered with anticoagulants, NSAIDs, platelet inhibitors, and thrombolytic agents.

• imipramine

  omeprazole will increase the level or effect of imipramine by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• indapamide

  aspirin increases and indapamide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• indomethacin

  aspirin and indomethacin both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and indomethacin both increase serum potassium. Use Caution/Monitor.

• insulin aspart

  aspirin increases effects of insulin aspart by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin aspart protamine/insulin aspart

  aspirin increases effects of insulin aspart protamine/insulin aspart by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin degludec

  aspirin increases effects of insulin degludec by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin degludec/insulin aspart

  aspirin, insulin degludec/insulin aspart. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.

• insulin detemir

  aspirin increases effects of insulin detemir by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin glargine

  aspirin increases effects of insulin glargine by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin glulisine

  aspirin increases effects of insulin glulisine by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin inhaled

  aspirin increases effects of insulin inhaled by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin isophane human/insulin regular human

  aspirin increases effects of insulin isophane human/insulin regular human by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin lispro

  aspirin increases effects of insulin lispro by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin lispro protamine/insulin lispro

  aspirin increases effects of insulin lispro protamine/insulin lispro by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin NPH

  aspirin increases effects of insulin NPH by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin regular human

  aspirin increases effects of insulin regular human by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• irbesartan

  irbesartan and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.

• iron dextran complex

  omeprazole will decrease the level or effect of iron dextran complex by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• iron sucrose

  omeprazole will decrease the level or effect of iron sucrose by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• isavuconazonium sulfate

  omeprazole will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• isoproterenol

  aspirin increases and isoproterenol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• istradefylline

  istradefylline will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates.

• ketoprofen

  aspirin and ketoprofen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and ketoprofen both increase serum potassium. Use Caution/Monitor.

• ketorolac

  aspirin and ketorolac both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and ketorolac both increase serum potassium. Use Caution/Monitor.

• ketorolac intranasal

  aspirin and ketorolac intranasal both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and ketorolac intranasal both increase serum potassium. Use Caution/Monitor.

• labetalol

  labetalol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of labetalol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• latanoprost

  latanoprost, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• latanoprostene bunod ophthalmic

  latanoprostene bunod ophthalmic, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• ledipasvir/sofosbuvir

  omeprazole decreases levels of ledipasvir/sofosbuvir by Other (see comment). Use Caution/Monitor. Comment: Ledipasvir solubility decreases as pH increases; drugs that increase gastric pH are expected to decrease levels of ledipasvir; proton-pump inhibitor doses comparable to omeprazole <20 mg can be administered simultaneously with ledipasvir/sofosbuvir under fasted conditions.

• lemborexant

  omeprazole will increase the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Lower nightly dose of lemborexant recommended if coadministered with weak CYP3A4 inhibitors. See drug monograph for specific dosage modification.

• letermovir

  letermovir increases levels of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor and dose adjustment may be necessary.

• levalbuterol

  aspirin increases and levalbuterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• levomilnacipran

  levomilnacipran, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. SNRIs may further impair platelet activity in patients taking antiplatelet or anticoagulant drugs.

• lisinopril

  lisinopril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.

• lithium

  aspirin increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.

• lomitapide

  omeprazole increases levels of lomitapide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lomitapide dose should not exceed 30 mg/day.

• lornoxicam

  aspirin and lornoxicam both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and lornoxicam both increase serum potassium. Use Caution/Monitor.

• losartan

  aspirin decreases effects of losartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  losartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  omeprazole will increase the level or effect of losartan by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. May inhibit the conversion of losartan to its active metabolite E-3174. Importance of interaction not established; monitor individual therapeutic response to determine losartan dosage.
  
  losartan and aspirin both increase serum potassium. Use Caution/Monitor.

• lumacaftor/ivacaftor

  lumacaftor/ivacaftor, omeprazole. affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. In vitro studies suggest that lumacaftor may induce and ivacaftor may inhibit CYP2C19 substrates. .
  
  lumacaftor/ivacaftor will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lumacaftor/ivacaftor is a strong CYP3A4 inhibitor and also has the potential to induce CYP2C19 and both induce and inhibitor P-gp.

• meclofenamate

  aspirin and meclofenamate both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and meclofenamate both increase serum potassium. Use Caution/Monitor.

• mefenamic acid

  aspirin and mefenamic acid both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and mefenamic acid both increase serum potassium. Use Caution/Monitor.

• melatonin

  melatonin increases effects of aspirin by anticoagulation. Use Caution/Monitor. Melatonin may decrease prothrombin time.

• meloxicam

  aspirin and meloxicam both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and meloxicam both increase serum potassium. Use Caution/Monitor.

• mesalamine

  mesalamine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive nephrotoxicity.

• metaproterenol

  aspirin increases and metaproterenol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• methazolamide

  methazolamide, aspirin. Either increases levels of the other by Other (see comment). Use Caution/Monitor. Comment: Carbonic anhydrase inhibitors (CAIs) and salicylates inhibit each other's renal tubular secretion, resulting in increased plasma levels. CAIs also shift salicylates from plasma to the CNS, leading to potential neurotoxicity.

• methotrexate

  omeprazole increases levels of methotrexate by decreasing renal clearance. Use Caution/Monitor. Temporary withdrawal of PPI may be considered in some patients.

• methyclothiazide

  aspirin increases and methyclothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor. .

• methylphenidate

  omeprazole decreases effects of methylphenidate by enhancing GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Since the characteristics of methylphenidate extended release capsules (Ritalin LA) are pH dependent, coadministration of antacids or acid suppressants could alter the release of methylphenidate. Consider separating the administration of the antacid and the methylphenidate extended-release capsules may be avoided.

• methylprednisolone

  aspirin, methylprednisolone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.

• metolazone

  aspirin increases and metolazone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• metoprolol

  metoprolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of metoprolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• midazolam intranasal

  omeprazole will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of mild CYP3A4 inhibitors with midazolam intranasal may cause higher midazolam systemic exposure, which may prolong sedation.

• milnacipran

  milnacipran, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• mistletoe

  aspirin increases and mistletoe decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• modafinil

  modafinil will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• moexipril

  moexipril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.

• moxisylyte

  aspirin decreases effects of moxisylyte by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• mycophenolate

  aspirin will increase the level or effect of mycophenolate by acidic (anionic) drug competition for renal tubular clearance. Use Caution/Monitor.
  
  omeprazole will decrease the level or effect of mycophenolate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor. Potential interaction applies to mycophenolate mofetil. Enteric coated mycophenolate sodium formulation is less sensitive to this interaction. Clinical significance unclear.

• nabumetone

  aspirin and nabumetone both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and nabumetone both increase serum potassium. Use Caution/Monitor.

• nateglinide

  omeprazole will increase the level or effect of nateglinide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• nadolol

  nadolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of nadolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• nafcillin

  nafcillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  nafcillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• naproxen

  aspirin and naproxen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and naproxen both increase serum potassium. Use Caution/Monitor.

• nebivolol

  nebivolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of nebivolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• nefazodone

  nefazodone, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• nettle

  aspirin increases and nettle decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• nitazoxanide

  nitazoxanide, aspirin. Either increases levels of the other by Mechanism: plasma protein binding competition. Use Caution/Monitor.

• nitroglycerin rectal

  aspirin will increase the level or effect of nitroglycerin rectal by Other (see comment). Use Caution/Monitor. The pharmacological effects of nitroglycerin may be enhanced by concomitant administration of aspirin.

• nitroglycerin sublingual

  aspirin increases effects of nitroglycerin sublingual by additive vasodilation. Use Caution/Monitor. Vasodilatory and hemodynamic effects of NTG may be enhanced by coadministration with aspirin (additive effect desirable for emergent treatment).

• norepinephrine

  aspirin increases and norepinephrine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• olmesartan

  olmesartan and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of olmesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  olmesartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.

• ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC)

  ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC) will decrease the level or effect of omeprazole by unspecified interaction mechanism. Use Caution/Monitor. Monitor for decreased omeprazole efficacy; consider increasing omeprazole dose in patients whose symptoms are not well controlled (not to exceed 40 mg/day)

• omega 3 carboxylic acids

  omega 3 carboxylic acids, aspirin. Other (see comment). Use Caution/Monitor. Comment: Patients taking omega-3 acids and an anticoagulant or other drug affecting coagulation should be monitored periodically due to potential increased risk of bleeding.

• omega 3 fatty acids

  omega 3 fatty acids, aspirin. Other (see comment). Use Caution/Monitor. Comment: Patients taking omega-3-fatty acids and an anticoagulant or other drug affecting coagulation should be monitored periodically due to potential increased risk of bleeding. .

• ospemifene

  aspirin, ospemifene. Either increases levels of the other by plasma protein binding competition. Modify Therapy/Monitor Closely.

• oxacillin

  oxacillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  oxacillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• oxaprozin

  aspirin and oxaprozin both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and oxaprozin both increase serum potassium. Use Caution/Monitor.

• oxcarbazepine

  oxcarbazepine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• panax ginseng

  aspirin and panax ginseng both increase anticoagulation. Use Caution/Monitor.

• parecoxib

  aspirin and parecoxib both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and parecoxib both increase serum potassium. Use Caution/Monitor.

• paroxetine

  paroxetine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• pau d'arco

  aspirin and pau d'arco both increase anticoagulation. Use Caution/Monitor.

• pegaspargase

  pegaspargase increases effects of aspirin by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of bleeding events.

• penbutolol

  penbutolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of penbutolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• penicillin G aqueous

  penicillin G aqueous, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  penicillin G aqueous, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• pentobarbital

  pentobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• perindopril

  perindopril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high doses of aspirin,in elderly or volume depleted individuals.

• phenindione

  phenindione and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• phenobarbital

  phenobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• phenoxybenzamine

  aspirin decreases effects of phenoxybenzamine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• phentolamine

  aspirin decreases effects of phentolamine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• phenytoin

  omeprazole will increase the level or effect of phenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  phenytoin will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• phytoestrogens

  aspirin and phytoestrogens both increase anticoagulation. Use Caution/Monitor.

• pindolol

  pindolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of pindolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• pirbuterol

  aspirin increases and pirbuterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• piroxicam

  aspirin and piroxicam both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and piroxicam both increase serum potassium. Use Caution/Monitor.

• pivmecillinam

  pivmecillinam, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  pivmecillinam, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• polysaccharide iron

  omeprazole will decrease the level or effect of polysaccharide iron by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• posaconazole

  omeprazole will decrease the level or effect of posaconazole by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.
  
  posaconazole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• potassium acid phosphate

  aspirin and potassium acid phosphate both increase serum potassium. Modify Therapy/Monitor Closely.

• potassium chloride

  aspirin and potassium chloride both increase serum potassium. Modify Therapy/Monitor Closely.

• potassium citrate

  aspirin and potassium citrate both increase serum potassium. Use Caution/Monitor.

• potassium iodide

  potassium iodide and aspirin both increase serum potassium. Use Caution/Monitor.

• prasugrel

  aspirin, prasugrel. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• prazosin

  aspirin decreases effects of prazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• prednisolone

  aspirin, prednisolone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.

• prednisone

  aspirin, prednisone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.

• primidone

  primidone will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  primidone will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• propranolol

  propranolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of propranolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• protamine

  protamine and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• quinapril

  quinapril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high doses of aspirin, in elderly or volume depleted individuals.

• ramipril

  ramipril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high doses of aspirin, in elderly or volume depleted individuals.

• reishi

  aspirin and reishi both increase anticoagulation. Use Caution/Monitor.

• reteplase

  aspirin, reteplase. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• rifampin

  rifampin will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• riociguat

  omeprazole will decrease the level or effect of riociguat by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ritonavir

  ritonavir will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• rivaroxaban

  aspirin, rivaroxaban. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. Both drugs have the potential to cause bleeding. The need for simultaneous use of low-dose aspirin (<100 mg/day) with anticoagulants are common for patients with cardiovascular disease, but may result in increased bleeding; monitor closely. Promptly evaluate any signs or symptoms of blood loss if treated concomitantly with low-dose aspirin. Avoid coadministration with chronic use of higher dose aspirin.

• rivastigmine

  rivastigmine increases toxicity of aspirin by pharmacodynamic synergism. Use Caution/Monitor. Monitor patients for symptoms of active or occult gastrointestinal bleeding.

• roflumilast

  omeprazole will decrease the level or effect of roflumilast by affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Concomitant therapy may reduce therapeutic effectiveness.

• rose hips

  omeprazole will decrease the level or effect of rose hips by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• sacubitril/valsartan

  sacubitril/valsartan and aspirin both increase serum potassium. Use Caution/Monitor.
  
  sacubitril/valsartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of sacubitril/valsartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.

• salicylates (non-asa)

  aspirin and salicylates (non-asa) both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and salicylates (non-asa) both increase serum potassium. Use Caution/Monitor.

• salmeterol

  aspirin increases and salmeterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• salsalate

  aspirin and salsalate both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and salsalate both increase serum potassium. Use Caution/Monitor.

• saw palmetto

  saw palmetto increases toxicity of aspirin by unspecified interaction mechanism. Use Caution/Monitor. May increase risk of bleeding.

• secobarbital

  secobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• selumetinib

  aspirin and selumetinib both increase anticoagulation. Modify Therapy/Monitor Closely. An increased risk of bleeding may occur in patients taking a vitamin-K antagonist or an antiplatelet agent with selumetinib. Monitor for bleeding and INR or PT in patients coadministered a vitamin-K antagonist or an antiplatelet agent with selumetinib.

• sertraline

  sertraline, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• Siberian ginseng

  aspirin and Siberian ginseng both increase anticoagulation. Use Caution/Monitor.

• silodosin

  aspirin decreases effects of silodosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• sodium picosulfate/magnesium oxide/anhydrous citric acid

  aspirin, sodium picosulfate/magnesium oxide/anhydrous citric acid. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May be associated with fluid and electrolyte imbalances.

• sodium sulfate/?magnesium sulfate/potassium chloride

  sodium sulfate/?magnesium sulfate/potassium chloride increases toxicity of aspirin by Other (see comment). Use Caution/Monitor. Comment: Coadministration with medications that cause fluid and electrolyte abnormalities may increase the risk of adverse events of seizure, arrhythmias, and renal impairment.

• sodium sulfate/potassium sulfate/magnesium sulfate

  sodium sulfate/potassium sulfate/magnesium sulfate increases toxicity of aspirin by Other (see comment). Use Caution/Monitor. Comment: Coadministration with medications that cause fluid and electrolyte abnormalities may increase the risk of adverse events of seizure, arrhythmias, and renal impairment.

• sotalol

  sotalol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of sotalol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• sparsentan

  aspirin and sparsentan both increase nephrotoxicity and/or ototoxicity. Use Caution/Monitor. Coadministration of NSAIDS, including selective COX-2 inhibitors, may result in deterioration of kidney function (eg, possible kidney failure). Monitor for signs of worsening renal function with concomitant use with NSAIDs.
  
  sparsentan will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Sparsentan (a CYP2C19 inducer) decreases exposure of CYP2C19 substrates and reduces efficacy related to these substrates.

• St John's Wort

  St John's Wort will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• spironolactone

  spironolactone and aspirin both increase serum potassium. Modify Therapy/Monitor Closely.
  
  aspirin decreases effects of spironolactone by unspecified interaction mechanism. Use Caution/Monitor. When used concomitantly, spironolactone dose may need to be titrated to higher maintenance dose and the patient should be observed closely to determine if the desired effect is obtained.

• stiripentol

  stiripentol, omeprazole. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP3A4 inhibitor and inducer. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. CYP3A4 substrates may require dosage adjustment.
  
  stiripentol will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider reducing the dose of CYP2C19 substrates, if adverse reactions are experienced when administered concomitantly with stiripentol.

• succinylcholine

  aspirin and succinylcholine both increase serum potassium. Use Caution/Monitor.

• sulfamethoxazole

  aspirin, sulfamethoxazole. Either increases effects of the other by plasma protein binding competition. Use Caution/Monitor. Due to high protein binding capacity of both drugs, one may displace the other when coadministered leading to an enhanced effect of the displaced drug; risk is low with low dose aspirin.

• sulfasalazine

  aspirin and sulfasalazine both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and sulfasalazine both increase serum potassium. Use Caution/Monitor.

• sulindac

  aspirin and sulindac both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and sulindac both increase serum potassium. Use Caution/Monitor.

• tacrolimus

  omeprazole will increase the level or effect of tacrolimus by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Concomitant administration may increase tacrolimus whole blood concentrations, particularly in intermediate or poor metabolizers of CYP2C19

• tafluprost

  tafluprost, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• tamoxifen

  omeprazole will increase the level or effect of tamoxifen by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• tazemetostat

  tazemetostat will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  omeprazole will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• telmisartan

  telmisartan and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of telmisartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  telmisartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.

• temocillin

  temocillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  temocillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• tenecteplase

  aspirin, tenecteplase. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• terazosin

  aspirin decreases effects of terazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• terbutaline

  aspirin increases and terbutaline decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• ticagrelor

  aspirin, ticagrelor. Other (see comment). Use Caution/Monitor. Comment: Maintenance doses of aspirin above 100 mg decreases effectiveness of ticagrelor. Therefore, after the initial loading dose of aspirin (usually 325 mg), use ticagrelor with a maintenance dose of aspirin of 75-100 mg.

• ticarcillin

  ticarcillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  ticarcillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• timolol

  timolol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of timolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.

• tinidazole

  omeprazole will increase the level or effect of tinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tirofiban

  aspirin, tirofiban. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• tobramycin inhaled

  tobramycin inhaled and aspirin both increase nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Avoid concurrent or sequential use to decrease risk for ototoxicity

• tofacitinib

  omeprazole increases levels of tofacitinib by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. No specific dose adjustment recommended when tofacitinib coadministered with potent CYP2C19 inhibitors; decrease tofacitinib dose if coadministered with both moderate CYP3A4 and potent CYP2C19 inhibitors .

• tolazamide

  aspirin increases effects of tolazamide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.

• tolbutamide

  aspirin increases effects of tolbutamide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.

• tolfenamic acid

  aspirin and tolfenamic acid both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and tolfenamic acid both increase serum potassium. Use Caution/Monitor.

• tolmetin

  aspirin and tolmetin both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and tolmetin both increase serum potassium. Use Caution/Monitor.

• tolvaptan

  aspirin and tolvaptan both increase serum potassium. Use Caution/Monitor.

• torsemide

  aspirin increases and torsemide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• trandolapril

  trandolapril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly and volume depleted.

• travoprost ophthalmic

  travoprost ophthalmic, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• trazodone

  trazodone, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• triamcinolone acetonide injectable suspension

  aspirin, triamcinolone acetonide injectable suspension. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Aspirin in conjunction with corticosteroids in hypoprothrombinemia should used with caution. Clearance of salicylates may increase with concurrent use of corticosteroids.

• triamterene

  triamterene and aspirin both increase serum potassium. Modify Therapy/Monitor Closely.

• triclabendazole

  triclabendazole will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• valproic acid

  aspirin increases levels of valproic acid by plasma protein binding competition. Use Caution/Monitor.

• valsartan

  valsartan and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of valsartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  valsartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.

• venlafaxine

  venlafaxine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• vismodegib

  omeprazole will decrease the level or effect of vismodegib by Other (see comment). Use Caution/Monitor. Drugs that increase gastric pH alter vismodegib solubility and therefore reduce bioavailability; effect on efficacy unknown

• voclosporin

  voclosporin, aspirin. Either increases toxicity of the other by nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Coadministration with drugs associated with nephrotoxicity may increase the risk for acute and/or chronic nephrotoxicity.

• vorapaxar

  aspirin, vorapaxar. Either increases effects of the other by anticoagulation. Use Caution/Monitor. Coadministration of anticoagulants, antiplatelets, or other drug affecting coagulation should be monitored periodically due to potential increased risk of bleeding.
  
  aspirin, vorapaxar. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive antiplatelet effect may occur.

• voriconazole

  voriconazole will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  voriconazole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• vortioxetine

  aspirin, vortioxetine. Either increases effects of the other by anticoagulation. Use Caution/Monitor. Risk minimal with low-dose aspirin.

• warfarin

  omeprazole will increase the level or effect of warfarin by Other (see comment). Use Caution/Monitor. Warfarin's less potent R-enantiomer is metabolized in part by CYP3A4 (and also CYP1A2 and CYP2C19). Monitor INR more frequently if coadministered with inhibitors of these isoenzymes and adjust warfarin dose if needed.
  
  aspirin increases effects of warfarin by anticoagulation. Modify Therapy/Monitor Closely. Avoid coadministration of chronic high-dose aspirin. Aspirin's antiplatelet properties may increase anticoagulation effect of warfarin. The need for simultaneous use of low-dose aspirin and warfarin is common for patients with cardiovascular disease. .

• zanubrutinib

  aspirin, zanubrutinib. Either increases effects of the other by anticoagulation. Modify Therapy/Monitor Closely. Zanubrutinib-induced cytopenias increases risk of hemorrhage. Coadministration of zanubritinib with antiplatelets or anticoagulants may further increase this risk.

• zotepine

  aspirin decreases effects of zotepine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

Minor (168)

• aceclofenac

  aceclofenac will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• acemetacin

  acemetacin will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• acetazolamide

  acetazolamide will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  aspirin will decrease the level or effect of acetazolamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• acyclovir

  aspirin will increase the level or effect of acyclovir by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• alosetron

  omeprazole will decrease the level or effect of alosetron by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• alendronate

  aspirin, alendronate. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of GI ulceration.

• alprazolam

  omeprazole increases levels of alprazolam by decreasing metabolism. Minor/Significance Unknown.

• aluminum hydroxide

  aluminum hydroxide, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Minor/Significance Unknown. Salicylate levels increased at moderate doses; salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• ambrisentan

  omeprazole will increase the level or effect of ambrisentan by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• amikacin

  aspirin increases levels of amikacin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• aminohippurate sodium

  aspirin will increase the level or effect of aminohippurate sodium by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• anamu

  aspirin and anamu both increase anticoagulation. Minor/Significance Unknown.

• anastrozole

  aspirin will decrease the level or effect of anastrozole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  anastrozole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ascorbic acid

  ascorbic acid will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  aspirin decreases levels of ascorbic acid by increasing renal clearance. Minor/Significance Unknown.
  
  ascorbic acid increases levels of aspirin by decreasing renal clearance. Minor/Significance Unknown.

• bismuth subsalicylate

  omeprazole increases levels of bismuth subsalicylate by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• balsalazide

  aspirin will increase the level or effect of balsalazide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• bendroflumethiazide

  bendroflumethiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• bismuth subsalicylate

  bismuth subsalicylate increases effects of aspirin by pharmacodynamic synergism. Minor/Significance Unknown.

• blessed thistle

  blessed thistle decreases effects of omeprazole by pharmacodynamic antagonism. Minor/Significance Unknown. Theoretical interaction.

• bosentan

  omeprazole will increase the level or effect of bosentan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  bosentan will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• bumetanide

  aspirin, bumetanide. Other (see comment). Minor/Significance Unknown. Comment: Salicylates are less likely than other NSAIDs to interact w/bumetanide.

• calcium carbonate

  calcium carbonate, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Minor/Significance Unknown. Salicylate levels increased at moderate doses; salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• carbamazepine

  omeprazole increases levels of carbamazepine by decreasing metabolism. Minor/Significance Unknown. Monitor plasma levels when used concomitantly.

• carvedilol

  omeprazole will increase the level or effect of carvedilol by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• cefadroxil

  cefadroxil will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefamandole

  cefamandole will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefepime

  cefepime will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefixime

  cefixime will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefpirome

  cefpirome will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefprozil

  cefprozil will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ceftazidime

  ceftazidime will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ceftibuten

  ceftibuten will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• celecoxib

  aspirin will increase the level or effect of celecoxib by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cephalexin

  cephalexin will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ceritinib

  aspirin will decrease the level or effect of ceritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• chlordiazepoxide

  omeprazole increases levels of chlordiazepoxide by decreasing metabolism. Minor/Significance Unknown.

• chlorothiazide

  chlorothiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• chlorpropamide

  aspirin will increase the level or effect of chlorpropamide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  aspirin increases effects of chlorpropamide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• chlorthalidone

  chlorthalidone will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• choline magnesium trisalicylate

  aspirin will increase the level or effect of choline magnesium trisalicylate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• chromium

  aspirin increases levels of chromium by unspecified interaction mechanism. Minor/Significance Unknown.

• clomipramine

  omeprazole will increase the level or effect of clomipramine by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• clonazepam

  omeprazole increases levels of clonazepam by decreasing metabolism. Minor/Significance Unknown.

• clorazepate

  omeprazole increases levels of clorazepate by decreasing metabolism. Minor/Significance Unknown.

• cortisone

  cortisone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• creatine

  creatine, aspirin. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. (Theoretical interaction) Combination may have additive nephrotoxic effects.

• cyanocobalamin

  aspirin decreases levels of cyanocobalamin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
  
  omeprazole decreases levels of cyanocobalamin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• cyclopenthiazide

  cyclopenthiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cyclophosphamide

  cyclophosphamide will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• cyclophosphamide

  aspirin will decrease the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• danshen

  aspirin and danshen both increase anticoagulation. Minor/Significance Unknown.

• darifenacin

  darifenacin will decrease the level or effect of omeprazole by Other (see comment). Minor/Significance Unknown. Effectiveness of proton pump inhibitors may be decreased theoretically if administered with other antisecretory agents

• deflazacort

  deflazacort decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• devil's claw

  aspirin and devil's claw both increase anticoagulation. Minor/Significance Unknown.
  
  devil's claw decreases effects of omeprazole by pharmacodynamic antagonism. Minor/Significance Unknown.

• dexamethasone

  dexamethasone will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  dexamethasone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• diazepam

  omeprazole will increase the level or effect of diazepam by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• diclofenac

  aspirin will increase the level or effect of diclofenac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• diclofenac topical

  diclofenac topical, aspirin. Either increases effects of the other by pharmacodynamic synergism. Minor/Significance Unknown. Although low, there is systemic exposure to diclofenac topical; theoretically, concomitant administration with systemic NSAIDS or aspirin may result in increased NSAID adverse effects.

• diflunisal

  aspirin will increase the level or effect of diflunisal by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• diltiazem

  diltiazem increases effects of aspirin by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.

• dronedarone

  dronedarone will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• elvitegravir/cobicistat/emtricitabine/tenofovir DF

  elvitegravir/cobicistat/emtricitabine/tenofovir DF, omeprazole. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Based on drug interaction studies conducted with the components of Stribild, no clinically significant drug interactions have been either observed or are expected when coadministered with PPIs.

• eplerenone

  aspirin decreases effects of eplerenone by pharmacodynamic antagonism. Minor/Significance Unknown. NSAIDs decrease prostaglandin synthesis.

• eslicarbazepine acetate

  eslicarbazepine acetate decreases effects of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Monitor for GI symptoms; net increased or decreased effect on PPI action unclear due to opposing CYP450 actions.

• estazolam

  omeprazole increases levels of estazolam by decreasing metabolism. Minor/Significance Unknown.

• ethanol

  ethanol increases toxicity of aspirin by pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of GI bleeding.

• etodolac

  aspirin will increase the level or effect of etodolac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• etravirine

  omeprazole will increase the level or effect of etravirine by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.
  
  omeprazole will increase the level or effect of etravirine by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• fenbufen

  aspirin will increase the level or effect of fenbufen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• fenoprofen

  aspirin will increase the level or effect of fenoprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ferric carboxymaltose

  omeprazole will decrease the level or effect of ferric carboxymaltose by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown.

• feverfew

  aspirin decreases effects of feverfew by pharmacodynamic antagonism. Minor/Significance Unknown.

• fludrocortisone

  fludrocortisone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• fluoxetine

  fluoxetine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• flurazepam

  omeprazole increases levels of flurazepam by decreasing metabolism. Minor/Significance Unknown.

• flurbiprofen

  aspirin will increase the level or effect of flurbiprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• fluvastatin

  omeprazole will increase the level or effect of fluvastatin by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• folic acid

  aspirin decreases levels of folic acid by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• furosemide

  aspirin decreases effects of furosemide by pharmacodynamic antagonism. Minor/Significance Unknown. NSAIDs decrease prostaglandin synthesis.

• ganciclovir

  aspirin will increase the level or effect of ganciclovir by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• gentamicin

  aspirin increases levels of gentamicin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• glimepiride

  aspirin increases effects of glimepiride by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• glipizide

  aspirin increases effects of glipizide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.
  
  omeprazole will increase the level or effect of glipizide by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• glyburide

  aspirin increases effects of glyburide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• ibuprofen IV

  omeprazole will increase the level or effect of ibuprofen IV by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• hydrochlorothiazide

  hydrochlorothiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• hydrocortisone

  hydrocortisone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• ibuprofen

  aspirin will increase the level or effect of ibuprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• imidapril

  aspirin decreases effects of imidapril by pharmacodynamic antagonism. Minor/Significance Unknown. NSAIDs decrease prostaglandin synthesis.

• indapamide

  indapamide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• indomethacin

  aspirin will increase the level or effect of indomethacin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ketoprofen

  aspirin will increase the level or effect of ketoprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ketorolac

  aspirin will increase the level or effect of ketorolac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ketorolac intranasal

  aspirin will increase the level or effect of ketorolac intranasal by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• L-methylfolate

  aspirin decreases levels of L-methylfolate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• larotrectinib

  larotrectinib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  aspirin will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• levoketoconazole

  levoketoconazole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  aspirin will decrease the level or effect of levoketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• levothyroxine

  omeprazole decreases levels of levothyroxine by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Conflicting evidence regarding this interaction exists.

• lornoxicam

  aspirin will increase the level or effect of lornoxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• lidocaine

  omeprazole will decrease the level or effect of lidocaine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• liothyronine

  omeprazole decreases levels of liothyronine by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Conflicting evidence regarding this interaction exists.

• liotrix

  omeprazole decreases levels of liotrix by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Conflicting evidence regarding this interaction exists.

• lisdexamfetamine

  omeprazole, lisdexamfetamine. Other (see comment). Minor/Significance Unknown. Comment: Reduced gastric acidity caused by proton pump inhibitors decreases time to Tmax for amphetamine and dextroamphetamine. AUC was unaffected. .

• lorazepam

  omeprazole increases levels of lorazepam by decreasing metabolism. Minor/Significance Unknown.

• meclofenamate

  aspirin will increase the level or effect of meclofenamate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• mefenamic acid

  aspirin will increase the level or effect of mefenamic acid by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• meloxicam

  aspirin will increase the level or effect of meloxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• mesalamine

  aspirin will increase the level or effect of mesalamine by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• methamphetamine

  omeprazole decreases levels of methamphetamine by Other (see comment). Minor/Significance Unknown. Comment: Time to maximum concentration (Tmax) of amphetamine is decreased compared to when administered alone; monitor patients for changes in clinical effect and adjust therapy based on clinical response.

• methyclothiazide

  methyclothiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• methylprednisolone

  methylprednisolone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• metolazone

  metolazone will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• mexiletine

  omeprazole will decrease the level or effect of mexiletine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• midazolam

  omeprazole increases levels of midazolam by decreasing metabolism. Minor/Significance Unknown.

• mitotane

  mitotane decreases levels of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.

• nabumetone

  aspirin will increase the level or effect of nabumetone by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• naproxen

  aspirin will increase the level or effect of naproxen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• neomycin PO

  aspirin increases levels of neomycin PO by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• noni juice

  aspirin and noni juice both increase serum potassium. Minor/Significance Unknown.

• ofloxacin

  ofloxacin, aspirin. Other (see comment). Minor/Significance Unknown. Comment: Risk of CNS stimulation/seizure. Mechanism: Displacement of GABA from receptors in brain.

• olanzapine

  omeprazole will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• ospemifene

  omeprazole increases levels of ospemifene by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• oxaprozin

  aspirin will increase the level or effect of oxaprozin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• parecoxib

  aspirin will increase the level or effect of parecoxib by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• paromomycin

  aspirin increases levels of paromomycin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• penicillin VK

  penicillin VK, aspirin. Either increases levels of the other by decreasing renal clearance. Minor/Significance Unknown.

• pentazocine

  aspirin, pentazocine. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Possible risk of renal papillary necrosis w/chronic Tx.

• phytoestrogens

  omeprazole decreases levels of phytoestrogens by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• piperacillin

  piperacillin, aspirin. Either increases effects of the other by receptor binding competition. Minor/Significance Unknown. Salicylic acid could be displaced from protein binding sites or it could itself displace other protein-bound drugs and result in an enhanced effect of the displaced drug.

• piroxicam

  aspirin will increase the level or effect of piroxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ponatinib

  omeprazole decreases levels of ponatinib by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown.

• prednisolone

  prednisolone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• prednisone

  prednisone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• quazepam

  omeprazole increases levels of quazepam by decreasing metabolism. Minor/Significance Unknown.

• ribociclib

  ribociclib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• riluzole

  omeprazole will decrease the level or effect of riluzole by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• rose hips

  rose hips will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  aspirin decreases levels of rose hips by increasing renal clearance. Minor/Significance Unknown.
  
  rose hips increases levels of aspirin by decreasing renal clearance. Minor/Significance Unknown.

• ruxolitinib

  omeprazole will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ruxolitinib topical

  omeprazole will increase the level or effect of ruxolitinib topical by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• salicylates (non-asa)

  aspirin will increase the level or effect of salicylates (non-asa) by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• salsalate

  aspirin will increase the level or effect of salsalate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• sodium bicarbonate

  sodium bicarbonate, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Minor/Significance Unknown. Salicylate levels increased at moderate doses; salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• sodium citrate/citric acid

  sodium citrate/citric acid, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Minor/Significance Unknown. Salicylate levels increased at moderate doses; salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• stiripentol

  aspirin will decrease the level or effect of stiripentol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• streptomycin

  aspirin increases levels of streptomycin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• sulfadiazine

  aspirin increases levels of sulfadiazine by unspecified interaction mechanism. Minor/Significance Unknown.

• sulfamethoxazole

  omeprazole will increase the level or effect of sulfamethoxazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• sulfasalazine

  aspirin will increase the level or effect of sulfasalazine by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• sulfisoxazole

  aspirin increases levels of sulfisoxazole by unspecified interaction mechanism. Minor/Significance Unknown.

• sulindac

  aspirin will increase the level or effect of sulindac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• teniposide

  aspirin increases levels of teniposide by unspecified interaction mechanism. Minor/Significance Unknown.

• theophylline

  omeprazole will decrease the level or effect of theophylline by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.
  
  omeprazole increases toxicity of theophylline by Other (see comment). Minor/Significance Unknown. Comment: Prolonged use of proton pump inhibitors can cause hypochlorhydria, which in turn causes peristalsis in small intestine to increase and peristalsis in the proximal colon to decrease; monitor for toxicity.

• thyroid desiccated

  omeprazole decreases levels of thyroid desiccated by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Conflicting evidence regarding this interaction exists.

• tiludronate

  aspirin decreases levels of tiludronate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• tizanidine

  omeprazole will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• tobramycin

  aspirin increases levels of tobramycin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• tolazamide

  aspirin increases effects of tolazamide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• tolbutamide

  omeprazole will increase the level or effect of tolbutamide by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  aspirin increases effects of tolbutamide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• tolfenamic acid

  aspirin will increase the level or effect of tolfenamic acid by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• triazolam

  omeprazole increases levels of triazolam by decreasing metabolism. Minor/Significance Unknown.

• tolmetin

  aspirin will increase the level or effect of tolmetin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• triamcinolone acetonide injectable suspension

  triamcinolone acetonide injectable suspension decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• triamterene

  triamterene, aspirin. Other (see comment). Minor/Significance Unknown. Comment: Risk of acute renal failure. Mechanism: NSAIDs decrease prostaglandin synthesis, which normally protect against nephrotoxicity.
  
  aspirin increases toxicity of triamterene by pharmacodynamic antagonism. Minor/Significance Unknown. NSAIDs decrease prostaglandin synthesis, increasing the risk of nephrotoxicity.

• valganciclovir

  aspirin will increase the level or effect of valganciclovir by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• vancomycin

  aspirin increases levels of vancomycin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in neonates.

• verapamil

  verapamil increases effects of aspirin by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.

• voriconazole

  omeprazole will increase the level or effect of voriconazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• willow bark

  aspirin will increase the level or effect of willow bark by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  willow bark increases effects of aspirin by pharmacodynamic synergism. Minor/Significance Unknown. Willow bark contains salicylic acid, which may have additive effects/toxicity with salicylate drugs.

• abametapir

  Serious - Use Alternative (1)abametapir will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For 2 weeks after abametapir application, avoid taking drugs that are CYP3A4 substrates. If not feasible, avoid use of abametapir.

• abciximab

  Monitor Closely (1)aspirin, abciximab. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• abrocitinib

  Contraindicated (1)abrocitinib and aspirin both increase anticoagulation. Contraindicated. Antiplatelet drugs, except for low-dose aspirin (=81 mg qDay), during the first 3 months of treatment are contraindicated.Monitor Closely (1)omeprazole will increase the level or effect of abrocitinib by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Start abrocitinib 50 mg qDay when coadministered with CYP2C19 inhibitors. If adequate response not achieved after 12 weeks, may increase to 100 mg qDay. Discontinue if inadequate response after dosage increase.Serious - Use Alternative (1)omeprazole will increase the level or effect of abrocitinib by decreasing metabolism. Avoid or Use Alternate Drug. Abrocitinib is a CYP2C9 and CYP2C19 substrate. Drugs that are moderate-to-strong inhibitors of both CYP2C9 and CYP2C19 increase systemic exposure of abrocitinib and its active metabolites, which may increase adverse effects.

• acalabrutinib

  Monitor Closely (1)acalabrutinib increases effects of aspirin by anticoagulation. Modify Therapy/Monitor Closely. Coadministration of acalabrutinib with antiplatelets or anticoagulants may further increase risk of hemorrhage. Monitor for signs of bleeding and consider the benefit-risk of withholding acalabrutinib for 3-7 days presurgery and postsurgery depending upon the type of surgery and the risk of bleeding.Serious - Use Alternative (1)omeprazole decreases levels of acalabrutinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Acalabrutinib solubility decreases with increasing gastric pH. Due to the long-lasting effect of PPIs, separation of doses may not eliminate the interaction.

• acebutolol

  Monitor Closely (2)aspirin decreases effects of acebutolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  acebutolol and aspirin both increase serum potassium. Use Caution/Monitor.

• aceclofenac

  Monitor Closely (2)aceclofenac and aspirin both increase anticoagulation. Use Caution/Monitor.
  
  aceclofenac and aspirin both increase serum potassium. Use Caution/Monitor.Minor (1)aceclofenac will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• acemetacin

  Monitor Closely (2)acemetacin and aspirin both increase anticoagulation. Use Caution/Monitor.
  
  acemetacin and aspirin both increase serum potassium. Use Caution/Monitor.Minor (1)acemetacin will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• acetazolamide

  Monitor Closely (2)acetazolamide, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Use Caution/Monitor. Salicylate levels increased at moderate doses; risk of CNS toxicity. Salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).
  
  acetazolamide, aspirin. Either increases levels of the other by Other (see comment). Use Caution/Monitor. Comment: Carbonic anhydrase inhibitors (CAIs) and salicylates inhibit each other's renal tubular secretion, resulting in increased plasma levels. CAIs also shift salicylates from plasma to the CNS, leading to potential neurotoxicity.Minor (2)acetazolamide will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  aspirin will decrease the level or effect of acetazolamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• acyclovir

  Minor (1)aspirin will increase the level or effect of acyclovir by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• agrimony

  Monitor Closely (1)aspirin and agrimony both increase anticoagulation. Use Caution/Monitor.

• albuterol

  Monitor Closely (1)aspirin increases and albuterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• alendronate

  Minor (1)aspirin, alendronate. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of GI ulceration.

• alfalfa

  Monitor Closely (1)aspirin and alfalfa both increase anticoagulation. Use Caution/Monitor.

• alfuzosin

  Monitor Closely (1)aspirin decreases effects of alfuzosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• aliskiren

  Monitor Closely (1)aspirin will decrease the level or effect of aliskiren by Other (see comment). Use Caution/Monitor. In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, coadministration of NSAIDs with drugs that affect RAAS may increase the risk of renal impairment (including acute renal failure) and cause loss of antihypertensive effect. Monitor renal function periodically.

• alosetron

  Minor (1)omeprazole will decrease the level or effect of alosetron by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• alprazolam

  Minor (1)omeprazole increases levels of alprazolam by decreasing metabolism. Minor/Significance Unknown.

• alteplase

  Monitor Closely (1)aspirin, alteplase. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• aluminum hydroxide

  Minor (1)aluminum hydroxide, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Minor/Significance Unknown. Salicylate levels increased at moderate doses; salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• ambrisentan

  Minor (1)omeprazole will increase the level or effect of ambrisentan by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• American ginseng

  Monitor Closely (1)aspirin and American ginseng both increase anticoagulation. Use Caution/Monitor.

• amikacin

  Minor (1)aspirin increases levels of amikacin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• amiloride

  Monitor Closely (1)amiloride and aspirin both increase serum potassium. Modify Therapy/Monitor Closely.

• aminohippurate sodium

  Minor (1)aspirin will increase the level or effect of aminohippurate sodium by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• amobarbital

  Monitor Closely (1)amobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• amoxicillin

  Monitor Closely (2)amoxicillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  amoxicillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• ampicillin

  Monitor Closely (2)omeprazole will decrease the level or effect of ampicillin by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.
  
  ampicillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.

• anagrelide

  Monitor Closely (2)aspirin, anagrelide. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; increases risk of bleeding; monitor closely.
  
  anagrelide, aspirin. Either increases toxicity of the other by Mechanism: pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; increases risk of bleeding; monitor closely.

• anamu

  Minor (1)aspirin and anamu both increase anticoagulation. Minor/Significance Unknown.

• anastrozole

  Minor (2)anastrozole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  aspirin will decrease the level or effect of anastrozole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• antithrombin alfa

  Monitor Closely (2)aspirin, antithrombin alfa. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.
  
  antithrombin alfa and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• antithrombin III

  Monitor Closely (2)aspirin, antithrombin III. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.
  
  antithrombin III and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• apalutamide

  Serious - Use Alternative (2)apalutamide will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug. Coadministration of apalutamide, a strong CYP2C19 inducer, with drugs that are CYP2C19 substrates can result in lower exposure to these medications. Avoid or substitute another drug for these medications when possible. Evaluate for loss of therapeutic effect if medication must be coadministered.
  
  apalutamide will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of apalutamide, a strong CYP3A4 inducer, with drugs that are CYP3A4 substrates can result in lower exposure to these medications. Avoid or substitute another drug for these medications when possible. Evaluate for loss of therapeutic effect if medication must be coadministered. Adjust dose according to prescribing information if needed.

• apixaban

  Monitor Closely (1)aspirin and apixaban both increase anticoagulation. Modify Therapy/Monitor Closely. Both drugs have the potential to cause bleeding. The need for simultaneous use of low-dose aspirin (<100 mg/day) with anticoagulants are common for patients with cardiovascular disease, but may result in increased bleeding; monitor closely. Promptly evaluate any signs or symptoms of blood loss if treated concomitantly with low-dose aspiriin. Avoid coadministration with chronic use of higher dose aspirin. In 1 trial (APPRAISE-2), therapy was terminated because of significantly increased bleeding when apixaban was administered with dual antiplatelet therapy (eg, aspirin plus clopidogrel) compared with single antiplatelet treatment

• arformoterol

  Monitor Closely (1)aspirin increases and arformoterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• argatroban

  Monitor Closely (2)aspirin, argatroban. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.
  
  argatroban and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• armodafinil

  Monitor Closely (1)armodafinil will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• ascorbic acid

  Minor (3)ascorbic acid will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  aspirin decreases levels of ascorbic acid by increasing renal clearance. Minor/Significance Unknown.
  
  ascorbic acid increases levels of aspirin by decreasing renal clearance. Minor/Significance Unknown.

• asenapine

  Monitor Closely (1)aspirin decreases effects of asenapine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• atazanavir

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of atazanavir by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Atazanavir solubility decreases as pH increases. Substantially reduced plasma concentrations of atazanavir are expected if PPIs are coadministered. PPI dose should not exceed a dose comparable to omeprazole 20 mg and must be taken ~12 h before atazanavir/ritonavir in treatment naive-patients. PPIs are not recommended in treatment-experienced taking atazanavir.

• atenolol

  Monitor Closely (2)aspirin decreases effects of atenolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  atenolol and aspirin both increase serum potassium. Use Caution/Monitor.

• avapritinib

  Monitor Closely (1)omeprazole will increase the level or effect of avapritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• axitinib

  Monitor Closely (1)omeprazole increases levels of axitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• azficel-T

  Monitor Closely (1)azficel-T, aspirin. Other (see comment). Use Caution/Monitor. Comment: Patients taking aspirin may experience increased bruising or bleeding at biopsy and/or injection sites. Concomitant use of aspirin is not recommended. .

• azilsartan

  Monitor Closely (2)aspirin, azilsartan. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of azilsartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.

• balsalazide

  Minor (1)aspirin will increase the level or effect of balsalazide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• belumosudil

  Monitor Closely (1)omeprazole will decrease the level or effect of belumosudil by increasing gastric pH. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Increase belumosudil dosage to 200 mg PO BID when coadministered with proton pump inhibitors.

• belzutifan

  Monitor Closely (1)omeprazole will increase the level or effect of belzutifan by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Belzutifan is a CYP2C19 substrate. Coadministration with CYP2C19 inhibitors may increase incidence or severity of adverse effects. Monitor for anemia and hypoxia and reduce belzutifan dose as recommended.

• bemiparin

  Monitor Closely (1)bemiparin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• benazepril

  Monitor Closely (1)benazepril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, benazepril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• bendamustine

  Monitor Closely (1)omeprazole decreases levels of bendamustine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Concentrations of active metabolites may be increased.

• bendroflumethiazide

  Monitor Closely (1)aspirin increases and bendroflumethiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)bendroflumethiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• betaxolol

  Monitor Closely (2)aspirin decreases effects of betaxolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  betaxolol and aspirin both increase serum potassium. Use Caution/Monitor.

• betrixaban

  Monitor Closely (1)aspirin, betrixaban. Either increases levels of the other by anticoagulation. Use Caution/Monitor.

• bimatoprost

  Monitor Closely (1)bimatoprost, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• bismuth subsalicylate

  Minor (2)bismuth subsalicylate increases effects of aspirin by pharmacodynamic synergism. Minor/Significance Unknown.
  
  omeprazole increases levels of bismuth subsalicylate by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• bisoprolol

  Monitor Closely (2)aspirin decreases effects of bisoprolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  bisoprolol and aspirin both increase serum potassium. Use Caution/Monitor.

• bivalirudin

  Monitor Closely (2)aspirin, bivalirudin. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.
  
  bivalirudin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• blessed thistle

  Minor (1)blessed thistle decreases effects of omeprazole by pharmacodynamic antagonism. Minor/Significance Unknown. Theoretical interaction.

• bortezomib

  Monitor Closely (1)bortezomib will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• bosentan

  Minor (2)omeprazole will increase the level or effect of bosentan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  bosentan will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• bosutinib

  Monitor Closely (1)omeprazole decreases levels of bosutinib by Other (see comment). Use Caution/Monitor. Comment: PPIs may decrease bosutinib concentration by ~45%; bosutinib displays pH-dependent solubility.

• brinzolamide

  Monitor Closely (1)brinzolamide, aspirin. Either increases levels of the other by Other (see comment). Use Caution/Monitor. Comment: Carbonic anhydrase inhibitors (CAIs) and salicylates inhibit each other's renal tubular secretion, resulting in increased plasma levels. CAIs also shift salicylates from plasma to the CNS, leading to potential neurotoxicity.

• budesonide

  Monitor Closely (1)omeprazole decreases effects of budesonide by increasing gastric pH. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Enteric-coated budesonide dissolves at pH >5.5. Also, dissolution of extended-release budesonide tablets is pH dependent. Coadministration with drugs that increase gastric pH may cause these budesonide products to prematurely dissolve, and possibly affect release properties and absorption of the drug in the duodenum.

• bumetanide

  Monitor Closely (2)aspirin decreases effects of bumetanide by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.
  
  aspirin increases and bumetanide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)aspirin, bumetanide. Other (see comment). Minor/Significance Unknown. Comment: Salicylates are less likely than other NSAIDs to interact w/bumetanide.

• butabarbital

  Monitor Closely (1)butabarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• butalbital

  Monitor Closely (1)butalbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• calcium carbonate

  Minor (1)calcium carbonate, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Minor/Significance Unknown. Salicylate levels increased at moderate doses; salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• candesartan

  Monitor Closely (3)candesartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of candesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  candesartan and aspirin both increase serum potassium. Use Caution/Monitor.

• cannabidiol

  Monitor Closely (2)omeprazole will increase the level or effect of cannabidiol by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider reducing the cannabidiol dose when coadministered with a strong CYP2C19 inhibitor.
  
  cannabidiol will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider reducing the dose of sensitive CYP2C19 substrates, as clinically appropriate, when coadministered with cannabidiol.

• capecitabine

  Monitor Closely (1)omeprazole decreases effects of capecitabine by unknown mechanism. Use Caution/Monitor. Retrospective data suggest elevated gastric pH caused by PPI use may impair capecitabine tablet dissolution and/or reduce absorption.

• caplacizumab

  Serious - Use Alternative (1)caplacizumab, aspirin. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug.

• captopril

  Monitor Closely (1)captopril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, captopril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• carbamazepine

  Monitor Closely (1)carbamazepine will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)carbamazepine will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.Minor (1)omeprazole increases levels of carbamazepine by decreasing metabolism. Minor/Significance Unknown. Monitor plasma levels when used concomitantly.

• carbenoxolone

  Monitor Closely (1)aspirin increases and carbenoxolone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• carbonyl iron

  Monitor Closely (1)omeprazole will decrease the level or effect of carbonyl iron by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• carvedilol

  Monitor Closely (2)carvedilol and aspirin both increase serum potassium. Use Caution/Monitor.
  
  aspirin decreases effects of carvedilol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.Minor (1)omeprazole will increase the level or effect of carvedilol by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• cefadroxil

  Minor (1)cefadroxil will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefamandole

  Minor (1)cefamandole will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefepime

  Minor (1)cefepime will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefixime

  Minor (1)cefixime will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefpirome

  Minor (1)cefpirome will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefpodoxime

  Monitor Closely (1)omeprazole decreases effects of cefpodoxime by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• cefprozil

  Minor (1)cefprozil will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ceftazidime

  Minor (1)ceftazidime will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ceftibuten

  Minor (1)ceftibuten will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cefuroxime

  Monitor Closely (1)omeprazole decreases effects of cefuroxime by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• celecoxib

  Monitor Closely (2)aspirin and celecoxib both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and celecoxib both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of celecoxib by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• celiprolol

  Monitor Closely (2)aspirin decreases effects of celiprolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  celiprolol and aspirin both increase serum potassium. Use Caution/Monitor.

• cenobamate

  Monitor Closely (2)cenobamate will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.
  
  cenobamate will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider a dose reduction of CYP2C19 substrates, as clinically appropriate, when used concomitantly with cenobamate.

• cephalexin

  Minor (1)cephalexin will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ceritinib

  Serious - Use Alternative (1)omeprazole decreases effects of ceritinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.Minor (1)aspirin will decrease the level or effect of ceritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• chlordiazepoxide

  Minor (1)omeprazole increases levels of chlordiazepoxide by decreasing metabolism. Minor/Significance Unknown.

• chlorothiazide

  Monitor Closely (1)aspirin increases and chlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)chlorothiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• chlorpropamide

  Monitor Closely (1)aspirin increases effects of chlorpropamide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.Minor (2)aspirin will increase the level or effect of chlorpropamide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  aspirin increases effects of chlorpropamide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• chlorthalidone

  Monitor Closely (1)aspirin increases and chlorthalidone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)chlorthalidone will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• choline magnesium trisalicylate

  Monitor Closely (2)aspirin and choline magnesium trisalicylate both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and choline magnesium trisalicylate both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of choline magnesium trisalicylate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• chromium

  Minor (1)aspirin increases levels of chromium by unspecified interaction mechanism. Minor/Significance Unknown.

• cilostazol

  Monitor Closely (1)aspirin, cilostazol. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.Serious - Use Alternative (1)omeprazole will increase the level or effect of cilostazol by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

• cinnamon

  Monitor Closely (1)aspirin and cinnamon both increase anticoagulation. Use Caution/Monitor.

• ciprofloxacin

  Monitor Closely (2)aspirin decreases levels of ciprofloxacin by Other (see comment). Use Caution/Monitor. Comment: Buffered aspirin may decrease absorption of quinolones. Consider administering 2 hr before or 6 hr after, buffered aspirin administration.
  
  omeprazole will decrease the level or effect of ciprofloxacin by unknown mechanism. Use Caution/Monitor. Absorption of the ciprofloxacin ER tablet was slightly diminished (20%) when coadministered with omeprazole.

• citalopram

  Monitor Closely (2)omeprazole will increase the level or effect of citalopram by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Citalopram 20 mg/day is the maximum recommended dose for patients taking CYP2C19 inhibitors because of the risk of QT prolongation.
  
  citalopram, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. If possible, avoid concurrent use.

• clobazam

  Monitor Closely (1)omeprazole will increase the level or effect of clobazam by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Dosage adjustment may be required; CYP2C19 inhibitors may result in increased exposure to N-desmethylclobazam (active metabolite).

• clomipramine

  Monitor Closely (1)clomipramine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. Clomipramine inhib. serotonin uptake by platelets.Minor (1)omeprazole will increase the level or effect of clomipramine by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• clonazepam

  Minor (1)omeprazole increases levels of clonazepam by decreasing metabolism. Minor/Significance Unknown.

• clopidogrel

  Monitor Closely (1)aspirin, clopidogrel. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.Serious - Use Alternative (1)omeprazole decreases effects of clopidogrel by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug. Clopidogrel efficacy may be reduced by drugs that inhibit CYP2C19. Inhibition of platelet aggregation by clopidogrel is entirely due to an active metabolite. Clopidogrel is metabolized to this active metabolite in part by CYP2C19. .

• clorazepate

  Minor (1)omeprazole increases levels of clorazepate by decreasing metabolism. Minor/Significance Unknown.

• clozapine

  Monitor Closely (1)omeprazole will decrease the level or effect of clozapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

• cobicistat

  Monitor Closely (1)cobicistat will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• collagenase clostridium histolyticum

  Monitor Closely (1)aspirin increases toxicity of collagenase clostridium histolyticum by anticoagulation. Use Caution/Monitor. Collagenase clostridium histolyticum has high incidence of ecchymosis/contusion at injection site; avoid concomitant anticoagulants (except for low-dose aspirin, ie, up to 150 mg/day).

• conivaptan

  Monitor Closely (1)conivaptan will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• cordyceps

  Monitor Closely (1)aspirin and cordyceps both increase anticoagulation. Use Caution/Monitor.

• cortisone

  Monitor Closely (1)aspirin, cortisone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.Minor (1)cortisone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• creatine

  Minor (1)creatine, aspirin. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. (Theoretical interaction) Combination may have additive nephrotoxic effects.

• crizotinib

  Monitor Closely (1)omeprazole will decrease the level or effect of crizotinib by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor. Drugs that elevate the gastric pH may decrease the solubility of crizotinib and subsequently reduce its bioavailability. However, no formal studies have been conducted.

• cyanocobalamin

  Minor (2)omeprazole decreases levels of cyanocobalamin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.
  
  aspirin decreases levels of cyanocobalamin by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• cyclopenthiazide

  Monitor Closely (1)aspirin increases and cyclopenthiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)cyclopenthiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cyclophosphamide

  Minor (2)cyclophosphamide will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  aspirin will decrease the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• cyclosporine

  Monitor Closely (1)omeprazole, cyclosporine. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Long-term use of PPIs may cause hypomagnesemia and increase this risk when coadministered with drugs that may also decrease magnesium levels.

• dabigatran

  Monitor Closely (1)dabigatran and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely. Both drugs have the potential to cause bleeding. The need for simultaneous use of low-dose aspirin (<100 mg/day) with anticoagulants are common for patients with cardiovascular disease, but may result in increased bleeding; monitor closely. Promptly evaluate any signs or symptoms of blood loss if treated concomitantly with low-dose aspirin. Avoid coadministration with chronic use of higher dose aspirin

• dabrafenib

  Monitor Closely (2)dabrafenib will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Use alternative if available
  
  omeprazole will decrease the level or effect of dabrafenib by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor. Drugs that alter upper GI tract pH (eg, PPIs, H2-blockers, antacids) may decrease dabrafenib solubility and reduce its bioavailability

• dacomitinib

  Serious - Use Alternative (1)omeprazole will increase the level or effect of dacomitinib by unspecified interaction mechanism. Avoid or Use Alternate Drug. Concomitant use with a PPI decreases dacomitinib concentrations, which may reduce dacomitinib efficacy. Avoid use of PPIs with dacomitinib. As an alternative to PPIs, use locally-acting antacids or an H2-receptor antagonist. Administer at least 6 hours before or 10 hours after taking an H2-receptor antagonist.

• dalteparin

  Monitor Closely (2)aspirin, dalteparin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.
  
  dalteparin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• danshen

  Minor (1)aspirin and danshen both increase anticoagulation. Minor/Significance Unknown.

• darifenacin

  Minor (1)darifenacin will decrease the level or effect of omeprazole by Other (see comment). Minor/Significance Unknown. Effectiveness of proton pump inhibitors may be decreased theoretically if administered with other antisecretory agents

• dasatinib

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of dasatinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• deferasirox

  Monitor Closely (1)deferasirox, aspirin. Other (see comment). Use Caution/Monitor. Comment: Combination may increase GI bleeding, ulceration and irritation. Use with caution.

• defibrotide

  Monitor Closely (1)defibrotide increases effects of aspirin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Defibrotide may enhance effects of platelet inhibitors.

• deflazacort

  Monitor Closely (1)aspirin, deflazacort. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.Minor (1)deflazacort decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• desirudin

  Monitor Closely (1)aspirin, desirudin. Either increases levels of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• devil's claw

  Minor (2)devil's claw decreases effects of omeprazole by pharmacodynamic antagonism. Minor/Significance Unknown.
  
  aspirin and devil's claw both increase anticoagulation. Minor/Significance Unknown.

• dexamethasone

  Monitor Closely (1)aspirin, dexamethasone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.Minor (2)dexamethasone will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  dexamethasone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• dextroamphetamine

  Monitor Closely (1)omeprazole, dextroamphetamine. Other (see comment). Use Caution/Monitor. Comment: Reduced gastric acidity caused by proton pump inhibitors decreases time to Tmax for amphetamine and dextroamphetamine. AUC was unaffected. .

• diazepam

  Minor (1)omeprazole will increase the level or effect of diazepam by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• diazepam intranasal

  Monitor Closely (1)omeprazole will increase the level or effect of diazepam intranasal by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Strong or moderate CYP2C19 inhibitors may decrease rate of diazepam elimination, thereby increasing adverse reactions to diazepam.

• dichlorphenamide

  Contraindicated (1)dichlorphenamide increases levels of aspirin by unknown mechanism. Contraindicated. Coadministration of dichlorphenamide with high-dose aspirin may increase salicylate levels. Anorexia, tachypnea, lethargy, and coma reported.Monitor Closely (1)dichlorphenamide and omeprazole both decrease serum potassium. Use Caution/Monitor.

• diclofenac

  Monitor Closely (2)aspirin and diclofenac both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and diclofenac both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of diclofenac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• diclofenac topical

  Minor (1)diclofenac topical, aspirin. Either increases effects of the other by pharmacodynamic synergism. Minor/Significance Unknown. Although low, there is systemic exposure to diclofenac topical; theoretically, concomitant administration with systemic NSAIDS or aspirin may result in increased NSAID adverse effects.

• dicloxacillin

  Monitor Closely (1)dicloxacillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.

• diflunisal

  Monitor Closely (2)aspirin and diflunisal both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and diflunisal both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of diflunisal by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• digoxin

  Monitor Closely (2)aspirin and digoxin both increase serum potassium. Use Caution/Monitor.
  
  omeprazole increases toxicity of digoxin by Other (see comment). Use Caution/Monitor. Comment: Prolonged use of PPIs may cause hypomagnesemia and increase risk for digoxin toxicity.Serious - Use Alternative (1)omeprazole will increase the level or effect of digoxin by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• diltiazem

  Minor (1)diltiazem increases effects of aspirin by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.

• dipyridamole

  Monitor Closely (1)aspirin, dipyridamole. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• dobutamine

  Monitor Closely (1)aspirin increases and dobutamine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• dong quai

  Monitor Closely (1)aspirin and dong quai both increase anticoagulation. Use Caution/Monitor.

• dopexamine

  Monitor Closely (1)aspirin increases and dopexamine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• doxazosin

  Monitor Closely (1)aspirin decreases effects of doxazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• dronedarone

  Minor (1)dronedarone will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• drospirenone

  Monitor Closely (1)drospirenone and aspirin both increase serum potassium. Modify Therapy/Monitor Closely.

• duloxetine

  Monitor Closely (1)duloxetine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.Serious - Use Alternative (1)omeprazole will decrease the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

• edoxaban

  Monitor Closely (1)edoxaban, aspirin. Either increases toxicity of the other by anticoagulation. Modify Therapy/Monitor Closely. Both drugs have the potential to cause bleeding. The need for simultaneous use of low-dose aspirin (<100 mg/day) with anticoagulants are common for patients with cardiovascular disease, but may result in increased bleeding; monitor closely. Promptly evaluate any signs or symptoms of blood loss if treated concomitantly with low-dose aspirin. Avoid coadministration with chronic use of higher dose aspirin.

• efavirenz

  Monitor Closely (2)efavirenz will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  efavirenz will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• elagolix

  Monitor Closely (2)elagolix will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak inhibitor of CYP2C19. No dose adjustments are needed for omeprazole with 40 mg/day or less. Consider omeprazole dose reduction with higher omeprazole doses (eg, dose for Zollinger-Ellison) if coadministered with elagolix.
  
  elagolix decreases levels of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.

• eltrombopag

  Monitor Closely (1)omeprazole will decrease the level or effect of eltrombopag by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

• eluxadoline

  Monitor Closely (1)omeprazole increases levels of eluxadoline by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. As a precautionary measure due to incomplete information on the metabolism of eluxadoline, use caution when coadministered with strong CYP2C19 inhibitors.

• elvitegravir/cobicistat/emtricitabine/tenofovir DF

  Monitor Closely (1)elvitegravir/cobicistat/emtricitabine/tenofovir DF, aspirin. Either increases toxicity of the other by decreasing renal clearance. Modify Therapy/Monitor Closely. Toxicity may result from coadministration of emtricitabine and tenofovir with other drugs that are also primarily excreted by glomerular filtration and/or active tubular secretion including high-dose or multiple-dose NSAIDs; alternatives to NSAIDs should be considered.Minor (1)elvitegravir/cobicistat/emtricitabine/tenofovir DF, omeprazole. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Based on drug interaction studies conducted with the components of Stribild, no clinically significant drug interactions have been either observed or are expected when coadministered with PPIs.

• enalapril

  Monitor Closely (1)enalapril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, enalapril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• encorafenib

  Monitor Closely (1)encorafenib, omeprazole. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Encorafenib both inhibits and induces CYP3A4 at clinically relevant plasma concentrations. Coadministration of encorafenib with sensitive CYP3A4 substrates may result in increased toxicity or decreased efficacy of these agents.

• enoxaparin

  Monitor Closely (2)enoxaparin and aspirin both increase anticoagulation. Use Caution/Monitor. Additive effects are intended when both drugs are prescribed as indicated for unstable angina, non-Q-wave MI, and STEMI
  
  aspirin, enoxaparin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• enzalutamide

  Serious - Use Alternative (1)enzalutamide will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• ephedrine

  Monitor Closely (1)aspirin increases and ephedrine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epinephrine

  Monitor Closely (1)aspirin increases and epinephrine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• epinephrine racemic

  Monitor Closely (1)aspirin increases and epinephrine racemic decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• eplerenone

  Minor (1)aspirin decreases effects of eplerenone by pharmacodynamic antagonism. Minor/Significance Unknown. NSAIDs decrease prostaglandin synthesis.

• epoprostenol

  Monitor Closely (1)aspirin and epoprostenol both increase anticoagulation. Use Caution/Monitor.

• eprosartan

  Monitor Closely (3)aspirin decreases effects of eprosartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  eprosartan and aspirin both increase serum potassium. Use Caution/Monitor.
  
  eprosartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.

• eptifibatide

  Monitor Closely (1)aspirin, eptifibatide. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• erdafitinib

  Serious - Use Alternative (1)omeprazole will increase the level or effect of erdafitinib by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug. If coadministration of a strong CYP2C9 inhibitors is unavoidable, closely monitor adverse reactions and modify dose of erdafitinib accordingly. If strong CYP2C9 inhibitor is discontinued, consider increasing erdafitinib dose in the absence of any drug-related toxicities.

• erlotinib

  Contraindicated (1)omeprazole decreases levels of erlotinib by Other (see comment). Contraindicated. Comment: Concomitant use of proton pump inhibitors with erlotinib should be avoided if possible. Drugs that alter pH of upper GI tract may alter the solubility of erlotinib and reduce its bioavailability. .

• escitalopram

  Monitor Closely (2)omeprazole will increase the level or effect of escitalopram by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  escitalopram, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• eslicarbazepine acetate

  Monitor Closely (1)eslicarbazepine acetate will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.Minor (1)eslicarbazepine acetate decreases effects of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Monitor for GI symptoms; net increased or decreased effect on PPI action unclear due to opposing CYP450 actions.

• esmolol

  Monitor Closely (2)aspirin decreases effects of esmolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  esmolol and aspirin both increase serum potassium. Use Caution/Monitor.

• estazolam

  Minor (1)omeprazole increases levels of estazolam by decreasing metabolism. Minor/Significance Unknown.

• ethacrynic acid

  Monitor Closely (1)aspirin increases and ethacrynic acid decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• ethanol

  Minor (1)ethanol increases toxicity of aspirin by pharmacodynamic synergism. Minor/Significance Unknown. Increased risk of GI bleeding.

• etodolac

  Monitor Closely (2)aspirin and etodolac both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and etodolac both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of etodolac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• etravirine

  Monitor Closely (1)etravirine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.Minor (2)omeprazole will increase the level or effect of etravirine by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.
  
  omeprazole will increase the level or effect of etravirine by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• fedratinib

  Monitor Closely (1)fedratinib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.Serious - Use Alternative (1)omeprazole will increase the level or effect of fedratinib by Other (see comment). Avoid or Use Alternate Drug. Avoid coadministration of fedratinib (a CYP3A4 and CYP2C19 substrate) with dual CYP3A4 and CYP2C19 inhibitor. Effect of coadministration of a dual CYP3A4 and CYP2C19 inhibitor with fedratinib has not been studied.

• fenbufen

  Monitor Closely (2)aspirin and fenbufen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and fenbufen both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of fenbufen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• fennel

  Monitor Closely (1)aspirin and fennel both increase anticoagulation. Use Caution/Monitor.

• fenoprofen

  Monitor Closely (2)aspirin and fenoprofen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and fenoprofen both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of fenoprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ferric carboxymaltose

  Minor (1)omeprazole will decrease the level or effect of ferric carboxymaltose by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown.

• ferric gluconate

  Monitor Closely (1)omeprazole will decrease the level or effect of ferric gluconate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ferric maltol

  Monitor Closely (1)omeprazole will decrease the level or effect of ferric maltol by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ferrous fumarate

  Monitor Closely (1)omeprazole will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ferrous gluconate

  Monitor Closely (1)omeprazole will decrease the level or effect of ferrous gluconate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ferrous sulfate

  Monitor Closely (1)omeprazole will decrease the level or effect of ferrous sulfate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• feverfew

  Monitor Closely (1)aspirin and feverfew both increase anticoagulation. Use Caution/Monitor.Minor (1)aspirin decreases effects of feverfew by pharmacodynamic antagonism. Minor/Significance Unknown.

• fexinidazole

  Monitor Closely (1)fexinidazole will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)fexinidazole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Fexinidazole inhibits CYP3A4. Coadministration may increase risk for adverse effects of CYP3A4 substrates.

• fezolinetant

  Contraindicated (1)omeprazole will increase the level or effect of fezolinetant by affecting hepatic enzyme CYP1A2 metabolism. Contraindicated. Fezolinetant AUC and peak plasma concentration are increased if coadministered with drugs that are weak, moderate, or strong CYP1A2 inhibitors

• finerenone

  Monitor Closely (1)omeprazole will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or weak CYP3A4 inhibitors. Adjust finererone dosage as needed.

• fish oil

  Monitor Closely (1)fish oil, aspirin. Other (see comment). Use Caution/Monitor. Comment: Patients taking fish oil and an anticoagulant or other drug affecting coagulation should be monitored periodically due to potential increased risk of bleeding. .

• fish oil triglycerides

  Monitor Closely (1)fish oil triglycerides will increase the level or effect of aspirin by anticoagulation. Use Caution/Monitor. Prolonged bleeding reported in patients taking antiplatelet agents or anticoagulants and oral omega-3 fatty acids. Periodically monitor bleeding time in patients receiving fish oil triglycerides and concomitant antiplatelet agents or anticoagulants.

• flibanserin

  Monitor Closely (2)omeprazole will increase the level or effect of flibanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Increased flibanserin adverse effects may occur if coadministered with multiple weak CYP3A4 inhibitors.
  
  omeprazole will increase the level or effect of flibanserin by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Coadministration of flibanserin with strong CYP2C19 inhibitors may increase flibanserin exposure and increase the risk of hypotension, syncope, and CNS depression.

• fluconazole

  Monitor Closely (1)fluconazole will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• fludrocortisone

  Monitor Closely (1)aspirin, fludrocortisone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.Minor (1)fludrocortisone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• fluoxetine

  Monitor Closely (1)fluoxetine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.Minor (1)fluoxetine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• flurazepam

  Minor (1)omeprazole increases levels of flurazepam by decreasing metabolism. Minor/Significance Unknown.

• flurbiprofen

  Monitor Closely (2)aspirin and flurbiprofen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and flurbiprofen both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of flurbiprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• fluvastatin

  Minor (1)omeprazole will increase the level or effect of fluvastatin by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• fluvoxamine

  Monitor Closely (1)fluvoxamine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding SSRIs inhib. serotonin uptake by platelets.Serious - Use Alternative (1)fluvoxamine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

• folic acid

  Minor (1)aspirin decreases levels of folic acid by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• fondaparinux

  Monitor Closely (1)fondaparinux and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• formoterol

  Monitor Closely (1)aspirin increases and formoterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• forskolin

  Monitor Closely (1)aspirin and forskolin both increase anticoagulation. Use Caution/Monitor.

• fosamprenavir

  Monitor Closely (1)omeprazole will decrease the level or effect of fosamprenavir by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• fosinopril

  Monitor Closely (1)fosinopril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, fosinopril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• fosphenytoin

  Monitor Closely (2)omeprazole will increase the level or effect of fosphenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  fosphenytoin will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• furosemide

  Monitor Closely (1)aspirin increases and furosemide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)aspirin decreases effects of furosemide by pharmacodynamic antagonism. Minor/Significance Unknown. NSAIDs decrease prostaglandin synthesis.

• ganciclovir

  Minor (1)aspirin will increase the level or effect of ganciclovir by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• garlic

  Monitor Closely (1)aspirin and garlic both increase anticoagulation. Use Caution/Monitor.

• gefitinib

  Monitor Closely (1)omeprazole decreases levels of gefitinib by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor. Avoid coadministration of gefitinib with PPIs if possible. If treatment with a PPI is required, separate gefitinib and PPI doses by 12 hr.

• gentamicin

  Monitor Closely (1)aspirin increases and gentamicin decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)aspirin increases levels of gentamicin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• ginger

  Monitor Closely (1)aspirin and ginger both increase anticoagulation. Use Caution/Monitor.

• ginkgo biloba

  Monitor Closely (1)aspirin and ginkgo biloba both increase anticoagulation. Use Caution/Monitor.

• glimepiride

  Monitor Closely (1)aspirin increases effects of glimepiride by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.Minor (1)aspirin increases effects of glimepiride by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• glipizide

  Monitor Closely (1)aspirin increases effects of glipizide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.Minor (2)omeprazole will increase the level or effect of glipizide by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.
  
  aspirin increases effects of glipizide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• glyburide

  Monitor Closely (2)omeprazole will increase the level or effect of glyburide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  aspirin increases effects of glyburide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.Minor (1)aspirin increases effects of glyburide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• green tea

  Monitor Closely (1)green tea increases effects of aspirin by pharmacodynamic synergism. Use Caution/Monitor. (Theoretical, due to caffeine content). Combination may increase risk of bleeding.

• griseofulvin

  Monitor Closely (1)griseofulvin decreases levels of aspirin by unknown mechanism. Use Caution/Monitor.

• heparin

  Monitor Closely (2)aspirin, heparin. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.
  
  heparin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• horse chestnut seed

  Monitor Closely (1)aspirin and horse chestnut seed both increase anticoagulation. Use Caution/Monitor.

• hyaluronidase

  Monitor Closely (1)aspirin decreases effects of hyaluronidase by Other (see comment). Use Caution/Monitor. Comment: Salicylates, when given in large systemic doses, may render tissues partially resistant to the action of hyaluronidase. Patients may require larger amounts of hyaluronidase for equivalent dispersing effect.

• hydralazine

  Monitor Closely (1)aspirin decreases effects of hydralazine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• hydrochlorothiazide

  Monitor Closely (1)aspirin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• hydrocortisone

  Monitor Closely (1)aspirin, hydrocortisone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.Minor (1)hydrocortisone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• ibrutinib

  Monitor Closely (1)ibrutinib will increase the level or effect of aspirin by anticoagulation. Use Caution/Monitor. Ibrutinib may increase the risk of hemorrhage in patients receiving antiplatelet or anticoagulant therapies and monitor for signs of bleeding.

• ibuprofen

  Monitor Closely (2)aspirin and ibuprofen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and ibuprofen both increase serum potassium. Use Caution/Monitor.Serious - Use Alternative (2)ibuprofen increases toxicity of aspirin by anticoagulation. Avoid or Use Alternate Drug. increases risk of bleeding.
  
  ibuprofen decreases effects of aspirin by Other (see comment). Avoid or Use Alternate Drug. Comment: Ibuprofen decreases the antiplatelet effects of low-dose aspirin by blocking the active site of platelet cyclooxygenase. Administer ibuprofen 8 h before aspirin or at least 2-4 h after aspirin. The effect of other NSAIDs on aspirin is not established.Minor (1)aspirin will increase the level or effect of ibuprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ibuprofen IV

  Monitor Closely (3)aspirin and ibuprofen IV both increase anticoagulation. Modify Therapy/Monitor Closely.
  
  aspirin and ibuprofen IV both increase serum potassium. Use Caution/Monitor.
  
  aspirin will increase the level or effect of ibuprofen IV by acidic (anionic) drug competition for renal tubular clearance. Modify Therapy/Monitor Closely.Minor (1)omeprazole will increase the level or effect of ibuprofen IV by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.Serious - Use Alternative (2)ibuprofen IV decreases effects of aspirin by Other (see comment). Avoid or Use Alternate Drug. Comment: Ibuprofen decreases the antiplatelet effects of low-dose aspirin by blocking the active site of platelet cyclooxygenase. Administer ibuprofen 8 h before aspirin or at least 2-4 h after aspirin. The effect of other NSAIDs on aspirin is not established.
  
  ibuprofen IV increases toxicity of aspirin by anticoagulation. Avoid or Use Alternate Drug. increases risk of bleeding.

• icosapent

  Monitor Closely (1)icosapent, aspirin. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Icosapent may prolong bleeding time; monitor periodically if coadministered with other drugs that affect bleeding.

• idelalisib

  Serious - Use Alternative (1)idelalisib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Idelalisib is a strong CYP3A inhibitor; avoid coadministration with sensitive CYP3A substrates

• iloperidone

  Monitor Closely (1)iloperidone increases levels of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Iloperidone is a time-dependent CYP3A inhibitor and may lead to increased plasma levels of drugs predominantly eliminated by CYP3A4.

• imatinib

  Monitor Closely (1)imatinib, aspirin. Either increases toxicity of the other by Other (see comment). Modify Therapy/Monitor Closely. Comment: Imatinib may cause thrombocytopenia; bleeding risk increased when imatinib is coadministered with anticoagulants, NSAIDs, platelet inhibitors, and thrombolytic agents.

• imidapril

  Minor (1)aspirin decreases effects of imidapril by pharmacodynamic antagonism. Minor/Significance Unknown. NSAIDs decrease prostaglandin synthesis.

• imipramine

  Monitor Closely (1)omeprazole will increase the level or effect of imipramine by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• indapamide

  Monitor Closely (1)aspirin increases and indapamide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)indapamide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• indinavir

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of indinavir by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• indomethacin

  Monitor Closely (2)aspirin and indomethacin both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and indomethacin both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of indomethacin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• infigratinib

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of infigratinib by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• insulin aspart

  Monitor Closely (1)aspirin increases effects of insulin aspart by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin aspart protamine/insulin aspart

  Monitor Closely (1)aspirin increases effects of insulin aspart protamine/insulin aspart by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin degludec

  Monitor Closely (1)aspirin increases effects of insulin degludec by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin degludec/insulin aspart

  Monitor Closely (1)aspirin, insulin degludec/insulin aspart. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.

• insulin detemir

  Monitor Closely (1)aspirin increases effects of insulin detemir by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin glargine

  Monitor Closely (1)aspirin increases effects of insulin glargine by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin glulisine

  Monitor Closely (1)aspirin increases effects of insulin glulisine by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin inhaled

  Monitor Closely (1)aspirin increases effects of insulin inhaled by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin isophane human/insulin regular human

  Monitor Closely (1)aspirin increases effects of insulin isophane human/insulin regular human by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin lispro

  Monitor Closely (1)aspirin increases effects of insulin lispro by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin lispro protamine/insulin lispro

  Monitor Closely (1)aspirin increases effects of insulin lispro protamine/insulin lispro by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin NPH

  Monitor Closely (1)aspirin increases effects of insulin NPH by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• insulin regular human

  Monitor Closely (1)aspirin increases effects of insulin regular human by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of insulin with high doses of salicylates (3 g/day or more) may increase risk for hypoglycemia. Insulin dose adjustment and increased frequency of glucose monitoring may be required.

• irbesartan

  Monitor Closely (3)irbesartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and aspirin both increase serum potassium. Use Caution/Monitor.

• iron dextran complex

  Monitor Closely (1)omeprazole will decrease the level or effect of iron dextran complex by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• iron sucrose

  Monitor Closely (1)omeprazole will decrease the level or effect of iron sucrose by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• isavuconazonium sulfate

  Monitor Closely (1)omeprazole will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• isoniazid

  Serious - Use Alternative (1)isoniazid will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

• isoproterenol

  Monitor Closely (1)aspirin increases and isoproterenol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• istradefylline

  Monitor Closely (1)istradefylline will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates.

• itraconazole

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of itraconazole by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• ivosidenib

  Serious - Use Alternative (1)ivosidenib will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternative therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs.

• ketoconazole

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of ketoconazole by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• ketoprofen

  Monitor Closely (2)aspirin and ketoprofen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and ketoprofen both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of ketoprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ketorolac

  Monitor Closely (2)aspirin and ketorolac both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and ketorolac both increase serum potassium. Use Caution/Monitor.Serious - Use Alternative (1)aspirin, ketorolac. Either increases toxicity of the other by pharmacodynamic synergism. Contraindicated.Minor (1)aspirin will increase the level or effect of ketorolac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ketorolac intranasal

  Monitor Closely (2)aspirin and ketorolac intranasal both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and ketorolac intranasal both increase serum potassium. Use Caution/Monitor.Serious - Use Alternative (1)aspirin, ketorolac intranasal. Either increases toxicity of the other by pharmacodynamic synergism. Contraindicated.Minor (1)aspirin will increase the level or effect of ketorolac intranasal by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• L-methylfolate

  Minor (1)aspirin decreases levels of L-methylfolate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• labetalol

  Monitor Closely (2)aspirin decreases effects of labetalol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  labetalol and aspirin both increase serum potassium. Use Caution/Monitor.

• larotrectinib

  Minor (2)larotrectinib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  aspirin will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• latanoprost

  Monitor Closely (1)latanoprost, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• latanoprostene bunod ophthalmic

  Monitor Closely (1)latanoprostene bunod ophthalmic, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• ledipasvir/sofosbuvir

  Monitor Closely (1)omeprazole decreases levels of ledipasvir/sofosbuvir by Other (see comment). Use Caution/Monitor. Comment: Ledipasvir solubility decreases as pH increases; drugs that increase gastric pH are expected to decrease levels of ledipasvir; proton-pump inhibitor doses comparable to omeprazole <20 mg can be administered simultaneously with ledipasvir/sofosbuvir under fasted conditions.

• lemborexant

  Monitor Closely (1)omeprazole will increase the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Lower nightly dose of lemborexant recommended if coadministered with weak CYP3A4 inhibitors. See drug monograph for specific dosage modification.

• lesinurad

  Serious - Use Alternative (1)aspirin decreases effects of lesinurad by unspecified interaction mechanism. Avoid or Use Alternate Drug. Aspirin at doses >325 mg/day may decrease lesinurad efficacy. Aspirin doses 325 mg/day or less (ie, for cardiovascular event prophylaxis) does not decrease lesinurad efficacy and can be coadministered.

• letermovir

  Monitor Closely (1)letermovir increases levels of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor and dose adjustment may be necessary.

• levalbuterol

  Monitor Closely (1)aspirin increases and levalbuterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• levoketoconazole

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of levoketoconazole by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.Minor (2)levoketoconazole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.
  
  aspirin will decrease the level or effect of levoketoconazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• levomilnacipran

  Monitor Closely (1)levomilnacipran, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. SNRIs may further impair platelet activity in patients taking antiplatelet or anticoagulant drugs.

• levothyroxine

  Minor (1)omeprazole decreases levels of levothyroxine by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Conflicting evidence regarding this interaction exists.

• lidocaine

  Minor (1)omeprazole will decrease the level or effect of lidocaine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• liothyronine

  Minor (1)omeprazole decreases levels of liothyronine by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Conflicting evidence regarding this interaction exists.

• liotrix

  Minor (1)omeprazole decreases levels of liotrix by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Conflicting evidence regarding this interaction exists.

• lisdexamfetamine

  Minor (1)omeprazole, lisdexamfetamine. Other (see comment). Minor/Significance Unknown. Comment: Reduced gastric acidity caused by proton pump inhibitors decreases time to Tmax for amphetamine and dextroamphetamine. AUC was unaffected. .

• lisinopril

  Monitor Closely (1)lisinopril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, lisinopril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• lithium

  Monitor Closely (1)aspirin increases levels of lithium by decreasing renal clearance. Use Caution/Monitor.

• lomitapide

  Monitor Closely (1)omeprazole increases levels of lomitapide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lomitapide dose should not exceed 30 mg/day.

• lonafarnib

  Serious - Use Alternative (2)omeprazole will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of lonafarnib (a sensitive CYP3A substrate) with weak CYP3A inhibitors is unavoidable, reduce to, or continue lonafarnib at starting dose. Closely monitor for arrhythmias and events (eg, syncope, heart palpitations) since lonafarnib effect on QT interval is unknown.
  
  lonafarnib will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug. Lonafarnib may increase the AUC and peak concentration of CYP2C19 substrates. If coadministration unavoidable, monitor for adverse reactions and reduce the CYP2C19 substrate dose in accordance with its approved product labeling.

• lorazepam

  Minor (1)omeprazole increases levels of lorazepam by decreasing metabolism. Minor/Significance Unknown.

• lornoxicam

  Monitor Closely (2)aspirin and lornoxicam both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and lornoxicam both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of lornoxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• losartan

  Monitor Closely (4)aspirin decreases effects of losartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  losartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  omeprazole will increase the level or effect of losartan by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. May inhibit the conversion of losartan to its active metabolite E-3174. Importance of interaction not established; monitor individual therapeutic response to determine losartan dosage.
  
  losartan and aspirin both increase serum potassium. Use Caution/Monitor.

• lumacaftor/ivacaftor

  Monitor Closely (2)lumacaftor/ivacaftor will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lumacaftor/ivacaftor is a strong CYP3A4 inhibitor and also has the potential to induce CYP2C19 and both induce and inhibitor P-gp.
  
  lumacaftor/ivacaftor, omeprazole. affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. In vitro studies suggest that lumacaftor may induce and ivacaftor may inhibit CYP2C19 substrates. .

• macimorelin

  Serious - Use Alternative (1)aspirin, macimorelin. unspecified interaction mechanism. Avoid or Use Alternate Drug. Drugs that directly affect the pituitary secretion of growth hormone (GH) may impact the accuracy of the macimorelin diagnostic test. Allow sufficient washout time of drugs affecting GH release before administering macimorelin. .

• mavacamten

  Contraindicated (1)omeprazole will increase the level or effect of mavacamten by affecting hepatic enzyme CYP2C19 metabolism. Contraindicated. Strong or moderate CYP2C19 inhibitors may increase mavacamten systemic exposure, resulting in heart failure due to systolic dysfunction.

• measles, mumps, rubella and varicella vaccine, live

  Serious - Use Alternative (1)aspirin, measles, mumps, rubella and varicella vaccine, live. Mechanism: unspecified interaction mechanism. Avoid or Use Alternate Drug. Risk of Reye's Syndrome with combination; avoid salicylate use for 6 wks after vaccination.

• meclofenamate

  Monitor Closely (2)aspirin and meclofenamate both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and meclofenamate both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of meclofenamate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• mefenamic acid

  Monitor Closely (2)aspirin and mefenamic acid both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and mefenamic acid both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of mefenamic acid by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• melatonin

  Monitor Closely (1)melatonin increases effects of aspirin by anticoagulation. Use Caution/Monitor. Melatonin may decrease prothrombin time.

• meloxicam

  Monitor Closely (2)aspirin and meloxicam both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and meloxicam both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of meloxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• mesalamine

  Monitor Closely (1)mesalamine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive nephrotoxicity.Serious - Use Alternative (1)omeprazole decreases effects of mesalamine by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Applies only to sustained release dosage form.Minor (1)aspirin will increase the level or effect of mesalamine by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• metaproterenol

  Monitor Closely (1)aspirin increases and metaproterenol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• methamphetamine

  Minor (1)omeprazole decreases levels of methamphetamine by Other (see comment). Minor/Significance Unknown. Comment: Time to maximum concentration (Tmax) of amphetamine is decreased compared to when administered alone; monitor patients for changes in clinical effect and adjust therapy based on clinical response.

• methazolamide

  Monitor Closely (1)methazolamide, aspirin. Either increases levels of the other by Other (see comment). Use Caution/Monitor. Comment: Carbonic anhydrase inhibitors (CAIs) and salicylates inhibit each other's renal tubular secretion, resulting in increased plasma levels. CAIs also shift salicylates from plasma to the CNS, leading to potential neurotoxicity.

• methotrexate

  Monitor Closely (1)omeprazole increases levels of methotrexate by decreasing renal clearance. Use Caution/Monitor. Temporary withdrawal of PPI may be considered in some patients.Serious - Use Alternative (1)aspirin increases levels of methotrexate by decreasing renal clearance. Avoid or Use Alternate Drug. Caution should be exercised when salicylates are given in combination with methotrexate. Risk for drug interactions with methotrexate is greatest during high-dose methotrexate therapy, it has been recommended that any of these drugs be used cautiously with methotrexate even when methotrexate is used in low doses.

• methyclothiazide

  Monitor Closely (1)aspirin increases and methyclothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor. .Minor (1)methyclothiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• methylphenidate

  Monitor Closely (1)omeprazole decreases effects of methylphenidate by enhancing GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Since the characteristics of methylphenidate extended release capsules (Ritalin LA) are pH dependent, coadministration of antacids or acid suppressants could alter the release of methylphenidate. Consider separating the administration of the antacid and the methylphenidate extended-release capsules may be avoided.

• methylprednisolone

  Monitor Closely (1)aspirin, methylprednisolone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.Minor (1)methylprednisolone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• metolazone

  Monitor Closely (1)aspirin increases and metolazone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)metolazone will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• metoprolol

  Monitor Closely (2)aspirin decreases effects of metoprolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  metoprolol and aspirin both increase serum potassium. Use Caution/Monitor.

• mexiletine

  Minor (1)omeprazole will decrease the level or effect of mexiletine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• midazolam

  Minor (1)omeprazole increases levels of midazolam by decreasing metabolism. Minor/Significance Unknown.

• midazolam intranasal

  Monitor Closely (1)omeprazole will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of mild CYP3A4 inhibitors with midazolam intranasal may cause higher midazolam systemic exposure, which may prolong sedation.

• mifepristone

  Contraindicated (1)aspirin, mifepristone. Other (see comment). Contraindicated. Comment: Aspirin induced antiplatelet activity may induce excessive bleeding after an abortion w/mifepristone (RU 486).Serious - Use Alternative (1)aspirin will decrease the level or effect of mifepristone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• milnacipran

  Monitor Closely (1)milnacipran, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• mistletoe

  Monitor Closely (1)aspirin increases and mistletoe decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• mitotane

  Minor (1)mitotane decreases levels of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.Serious - Use Alternative (1)aspirin will decrease the level or effect of mitotane by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• modafinil

  Monitor Closely (1)modafinil will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• moexipril

  Monitor Closely (1)moexipril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, moexipril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• moxisylyte

  Monitor Closely (1)aspirin decreases effects of moxisylyte by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• mycophenolate

  Monitor Closely (2)aspirin will increase the level or effect of mycophenolate by acidic (anionic) drug competition for renal tubular clearance. Use Caution/Monitor.
  
  omeprazole will decrease the level or effect of mycophenolate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor. Potential interaction applies to mycophenolate mofetil. Enteric coated mycophenolate sodium formulation is less sensitive to this interaction. Clinical significance unclear.

• nabumetone

  Monitor Closely (2)aspirin and nabumetone both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and nabumetone both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of nabumetone by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• nadolol

  Monitor Closely (2)aspirin decreases effects of nadolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  nadolol and aspirin both increase serum potassium. Use Caution/Monitor.

• nafcillin

  Monitor Closely (2)nafcillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  nafcillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• naproxen

  Monitor Closely (2)aspirin and naproxen both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and naproxen both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of naproxen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• nateglinide

  Monitor Closely (1)omeprazole will increase the level or effect of nateglinide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• nebivolol

  Monitor Closely (2)aspirin decreases effects of nebivolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  nebivolol and aspirin both increase serum potassium. Use Caution/Monitor.

• nefazodone

  Monitor Closely (1)nefazodone, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• nelfinavir

  Contraindicated (1)omeprazole decreases levels of nelfinavir by unspecified interaction mechanism. Contraindicated. Coadministration may lead to loss of nelfinavir virologic response and development of resistance; mechanism may be CYP2C19 inhibition of nelfinavir conversion to active M8 metabolite, and also PPIs decreasing gastric pH resulting in decreased nelfinavir absorption.

• neomycin PO

  Minor (1)aspirin increases levels of neomycin PO by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• neratinib

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of neratinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• nettle

  Monitor Closely (1)aspirin increases and nettle decreases anticoagulation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• nilotinib

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of nilotinib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Nilotinib has a pH-dependent solubility and solubility is decreased at higher pH; separating doses may not eliminate this effect because of PPI extended duration of action

• nisoldipine

  Serious - Use Alternative (1)omeprazole will increase the level or effect of nisoldipine by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug.

• nitazoxanide

  Monitor Closely (1)nitazoxanide, aspirin. Either increases levels of the other by Mechanism: plasma protein binding competition. Use Caution/Monitor.

• nitroglycerin rectal

  Monitor Closely (1)aspirin will increase the level or effect of nitroglycerin rectal by Other (see comment). Use Caution/Monitor. The pharmacological effects of nitroglycerin may be enhanced by concomitant administration of aspirin.

• nitroglycerin sublingual

  Monitor Closely (1)aspirin increases effects of nitroglycerin sublingual by additive vasodilation. Use Caution/Monitor. Vasodilatory and hemodynamic effects of NTG may be enhanced by coadministration with aspirin (additive effect desirable for emergent treatment).

• noni juice

  Minor (1)aspirin and noni juice both increase serum potassium. Minor/Significance Unknown.

• norepinephrine

  Monitor Closely (1)aspirin increases and norepinephrine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• ofloxacin

  Minor (1)ofloxacin, aspirin. Other (see comment). Minor/Significance Unknown. Comment: Risk of CNS stimulation/seizure. Mechanism: Displacement of GABA from receptors in brain.

• olanzapine

  Minor (1)omeprazole will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• olmesartan

  Monitor Closely (3)olmesartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of olmesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  olmesartan and aspirin both increase serum potassium. Use Caution/Monitor.

• ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC)

  Monitor Closely (1)ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC) will decrease the level or effect of omeprazole by unspecified interaction mechanism. Use Caution/Monitor. Monitor for decreased omeprazole efficacy; consider increasing omeprazole dose in patients whose symptoms are not well controlled (not to exceed 40 mg/day)

• omega 3 carboxylic acids

  Monitor Closely (1)omega 3 carboxylic acids, aspirin. Other (see comment). Use Caution/Monitor. Comment: Patients taking omega-3 acids and an anticoagulant or other drug affecting coagulation should be monitored periodically due to potential increased risk of bleeding.

• omega 3 fatty acids

  Monitor Closely (1)omega 3 fatty acids, aspirin. Other (see comment). Use Caution/Monitor. Comment: Patients taking omega-3-fatty acids and an anticoagulant or other drug affecting coagulation should be monitored periodically due to potential increased risk of bleeding. .

• ospemifene

  Monitor Closely (1)aspirin, ospemifene. Either increases levels of the other by plasma protein binding competition. Modify Therapy/Monitor Closely.Minor (1)omeprazole increases levels of ospemifene by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• oxacillin

  Monitor Closely (2)oxacillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  oxacillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• oxaprozin

  Monitor Closely (2)aspirin and oxaprozin both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and oxaprozin both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of oxaprozin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• oxcarbazepine

  Monitor Closely (1)oxcarbazepine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• panax ginseng

  Monitor Closely (1)aspirin and panax ginseng both increase anticoagulation. Use Caution/Monitor.

• parecoxib

  Monitor Closely (2)aspirin and parecoxib both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and parecoxib both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of parecoxib by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• paromomycin

  Minor (1)aspirin increases levels of paromomycin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• paroxetine

  Monitor Closely (1)paroxetine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• pau d'arco

  Monitor Closely (1)aspirin and pau d'arco both increase anticoagulation. Use Caution/Monitor.

• pazopanib

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of pazopanib by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Avoid coadministration of pazopanib with drugs that raise gastric pH; consider short-acting antacids in place of PPIs and H2 antagonists; separate antacid and pazopanib dosing by several hours

• pegaspargase

  Monitor Closely (1)pegaspargase increases effects of aspirin by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of bleeding events.

• pemetrexed

  Serious - Use Alternative (1)aspirin increases levels of pemetrexed by unspecified interaction mechanism. Avoid or Use Alternate Drug. Interrupt dosing in all patients taking NSAIDs with long elimination half-lives for at least 5d before, the day of, and 2d following pemetrexed administration. If coadministration of an NSAID is necessary, closely monitor patients for toxicity, especially myelosuppression, renal toxicity, and GI toxicity.

• penbutolol

  Monitor Closely (2)aspirin decreases effects of penbutolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  penbutolol and aspirin both increase serum potassium. Use Caution/Monitor.

• penicillin G aqueous

  Monitor Closely (2)penicillin G aqueous, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  penicillin G aqueous, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• penicillin VK

  Minor (1)penicillin VK, aspirin. Either increases levels of the other by decreasing renal clearance. Minor/Significance Unknown.

• pentazocine

  Minor (1)aspirin, pentazocine. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Possible risk of renal papillary necrosis w/chronic Tx.

• pentobarbital

  Monitor Closely (1)pentobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• perindopril

  Monitor Closely (1)perindopril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high doses of aspirin,in elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, perindopril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• pexidartinib

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of pexidartinib by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Avoid coadministration of proton pump inhibitors (PPIs) with pexidartinib. Use H2-receptor antagonists or antacids if needed. When using alternatives to PPIs, administer pexidartinib 2 hr before or after taking locally-acting antacids OR administer pexidartinib at least 2 hr before or 10 hr after taking an H2-receptor antagonist.

• phenindione

  Monitor Closely (1)phenindione and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• phenobarbital

  Monitor Closely (1)phenobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)phenobarbital will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• phenoxybenzamine

  Monitor Closely (1)aspirin decreases effects of phenoxybenzamine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• phentolamine

  Monitor Closely (1)aspirin decreases effects of phentolamine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• phenytoin

  Monitor Closely (2)omeprazole will increase the level or effect of phenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.
  
  phenytoin will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• phytoestrogens

  Monitor Closely (1)aspirin and phytoestrogens both increase anticoagulation. Use Caution/Monitor.Minor (1)omeprazole decreases levels of phytoestrogens by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• pindolol

  Monitor Closely (2)aspirin decreases effects of pindolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  pindolol and aspirin both increase serum potassium. Use Caution/Monitor.

• piperacillin

  Minor (1)piperacillin, aspirin. Either increases effects of the other by receptor binding competition. Minor/Significance Unknown. Salicylic acid could be displaced from protein binding sites or it could itself displace other protein-bound drugs and result in an enhanced effect of the displaced drug.

• pirbuterol

  Monitor Closely (1)aspirin increases and pirbuterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• piroxicam

  Monitor Closely (2)aspirin and piroxicam both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and piroxicam both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of piroxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• pivmecillinam

  Monitor Closely (2)pivmecillinam, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  pivmecillinam, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• polysaccharide iron

  Monitor Closely (1)omeprazole will decrease the level or effect of polysaccharide iron by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ponatinib

  Minor (1)omeprazole decreases levels of ponatinib by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown.

• posaconazole

  Monitor Closely (2)omeprazole will decrease the level or effect of posaconazole by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.
  
  posaconazole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• potassium acid phosphate

  Monitor Closely (1)aspirin and potassium acid phosphate both increase serum potassium. Modify Therapy/Monitor Closely.

• potassium chloride

  Monitor Closely (1)aspirin and potassium chloride both increase serum potassium. Modify Therapy/Monitor Closely.

• potassium citrate

  Monitor Closely (1)aspirin and potassium citrate both increase serum potassium. Use Caution/Monitor.

• potassium iodide

  Monitor Closely (1)potassium iodide and aspirin both increase serum potassium. Use Caution/Monitor.

• prasugrel

  Monitor Closely (1)aspirin, prasugrel. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• prazosin

  Monitor Closely (1)aspirin decreases effects of prazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• prednisolone

  Monitor Closely (1)aspirin, prednisolone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.Minor (1)prednisolone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• prednisone

  Monitor Closely (1)aspirin, prednisone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of GI ulceration.Minor (1)prednisone decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• primidone

  Monitor Closely (2)primidone will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  primidone will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• probenecid

  Serious - Use Alternative (1)aspirin decreases effects of probenecid by acidic (anionic) drug competition for renal tubular clearance. Avoid or Use Alternate Drug. Aspirin decreases uricosuric action of probenecid.

• propranolol

  Monitor Closely (2)aspirin decreases effects of propranolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  propranolol and aspirin both increase serum potassium. Use Caution/Monitor.

• protamine

  Monitor Closely (1)protamine and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely.

• quazepam

  Minor (1)omeprazole increases levels of quazepam by decreasing metabolism. Minor/Significance Unknown.

• quinapril

  Monitor Closely (1)quinapril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high doses of aspirin, in elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, quinapril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• ramipril

  Monitor Closely (1)ramipril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high doses of aspirin, in elderly or volume depleted individuals.Serious - Use Alternative (1)aspirin, ramipril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• reishi

  Monitor Closely (1)aspirin and reishi both increase anticoagulation. Use Caution/Monitor.

• reteplase

  Monitor Closely (1)aspirin, reteplase. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• ribociclib

  Minor (1)ribociclib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• rifampin

  Monitor Closely (1)rifampin will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)rifampin will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• rifapentine

  Serious - Use Alternative (1)rifapentine will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• rilpivirine

  Contraindicated (1)omeprazole decreases levels of rilpivirine by increasing gastric pH. Applies only to oral form of both agents. Contraindicated. Concurrent use may cause treatment failure and/or the development of rilpivirine or NNRTI resistance owing to decreased levels.

• riluzole

  Minor (1)omeprazole will decrease the level or effect of riluzole by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• riociguat

  Monitor Closely (1)omeprazole will decrease the level or effect of riociguat by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.

• ritonavir

  Monitor Closely (1)ritonavir will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• rivaroxaban

  Monitor Closely (1)aspirin, rivaroxaban. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. Both drugs have the potential to cause bleeding. The need for simultaneous use of low-dose aspirin (<100 mg/day) with anticoagulants are common for patients with cardiovascular disease, but may result in increased bleeding; monitor closely. Promptly evaluate any signs or symptoms of blood loss if treated concomitantly with low-dose aspirin. Avoid coadministration with chronic use of higher dose aspirin.

• rivastigmine

  Monitor Closely (1)rivastigmine increases toxicity of aspirin by pharmacodynamic synergism. Use Caution/Monitor. Monitor patients for symptoms of active or occult gastrointestinal bleeding.

• roflumilast

  Monitor Closely (1)omeprazole will decrease the level or effect of roflumilast by affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Concomitant therapy may reduce therapeutic effectiveness.

• rose hips

  Monitor Closely (1)omeprazole will decrease the level or effect of rose hips by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.Minor (3)aspirin decreases levels of rose hips by increasing renal clearance. Minor/Significance Unknown.
  
  rose hips will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  rose hips increases levels of aspirin by decreasing renal clearance. Minor/Significance Unknown.

• ruxolitinib

  Minor (1)omeprazole will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• ruxolitinib topical

  Minor (1)omeprazole will increase the level or effect of ruxolitinib topical by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• sacubitril/valsartan

  Monitor Closely (3)sacubitril/valsartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of sacubitril/valsartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  sacubitril/valsartan and aspirin both increase serum potassium. Use Caution/Monitor.

• salicylates (non-asa)

  Monitor Closely (2)aspirin and salicylates (non-asa) both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and salicylates (non-asa) both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of salicylates (non-asa) by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• salmeterol

  Monitor Closely (1)aspirin increases and salmeterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• salsalate

  Monitor Closely (2)aspirin and salsalate both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and salsalate both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of salsalate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• saw palmetto

  Monitor Closely (1)saw palmetto increases toxicity of aspirin by unspecified interaction mechanism. Use Caution/Monitor. May increase risk of bleeding.

• secobarbital

  Monitor Closely (1)secobarbital will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)secobarbital will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

• secretin

  Serious - Use Alternative (1)omeprazole, secretin. Other (see comment). Avoid or Use Alternate Drug. Comment: Concomitant use of PPIs may cause a hyperresponse in gastrin secretion in response to stimulation testing with secretin, falsely suggesting gastrinoma. The time it takes for serum gastrin concentrations to return to baseline following discontinuation of PPIs is specific to the individual PPI. Temporarily stop omeprazole treatment at least 14 days before assessing to allow gastrin levels to return to baseline.

• selumetinib

  Monitor Closely (1)aspirin and selumetinib both increase anticoagulation. Modify Therapy/Monitor Closely. An increased risk of bleeding may occur in patients taking a vitamin-K antagonist or an antiplatelet agent with selumetinib. Monitor for bleeding and INR or PT in patients coadministered a vitamin-K antagonist or an antiplatelet agent with selumetinib.

• sertraline

  Monitor Closely (1)sertraline, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• Siberian ginseng

  Monitor Closely (1)aspirin and Siberian ginseng both increase anticoagulation. Use Caution/Monitor.

• silodosin

  Monitor Closely (1)aspirin decreases effects of silodosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• siponimod

  Serious - Use Alternative (1)omeprazole will increase the level or effect of siponimod by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with drugs that cause moderate CYP2C9 AND a moderate or strong CYP3A4 inhibition is not recommended. Caution if siponimod coadministered with moderate CYP2C9 inhibitors alone.

• sodium bicarbonate

  Minor (1)sodium bicarbonate, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Minor/Significance Unknown. Salicylate levels increased at moderate doses; salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• sodium citrate/citric acid

  Minor (1)sodium citrate/citric acid, aspirin. Mechanism: passive renal tubular reabsorption due to increased pH. Minor/Significance Unknown. Salicylate levels increased at moderate doses; salicylate levels decreased at large doses (d/t increased renal excretion of unchanged salicylic acid).

• sodium picosulfate/magnesium oxide/anhydrous citric acid

  Monitor Closely (1)aspirin, sodium picosulfate/magnesium oxide/anhydrous citric acid. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May be associated with fluid and electrolyte imbalances.

• sodium sulfate/?magnesium sulfate/potassium chloride

  Monitor Closely (1)sodium sulfate/?magnesium sulfate/potassium chloride increases toxicity of aspirin by Other (see comment). Use Caution/Monitor. Comment: Coadministration with medications that cause fluid and electrolyte abnormalities may increase the risk of adverse events of seizure, arrhythmias, and renal impairment.

• sodium sulfate/potassium sulfate/magnesium sulfate

  Monitor Closely (1)sodium sulfate/potassium sulfate/magnesium sulfate increases toxicity of aspirin by Other (see comment). Use Caution/Monitor. Comment: Coadministration with medications that cause fluid and electrolyte abnormalities may increase the risk of adverse events of seizure, arrhythmias, and renal impairment.

• sofosbuvir/velpatasvir

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of sofosbuvir/velpatasvir by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Velpatasvir solubility decreases as gastric pH increases (practically insoluble at pH >5). Coadministration of sofosbuvir/velpatasvir with omeprazole or other PPIs is not recommended. If considered medically necessary, give sofosbuvir/velpatasvir with food 4 hr before omeprazole 20 mg. Use with other PPIs has not been studied.

• sotalol

  Monitor Closely (2)aspirin decreases effects of sotalol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  sotalol and aspirin both increase serum potassium. Use Caution/Monitor.

• sotorasib

  Serious - Use Alternative (1)omeprazole will decrease the level or effect of sotorasib by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug. If use with an acid-reducing agent cannot be avoided, administer sotorasib 4 hr before or 10 hr after administration of a locally-acting antacid.

• sparsentan

  Monitor Closely (2)aspirin and sparsentan both increase nephrotoxicity and/or ototoxicity. Use Caution/Monitor. Coadministration of NSAIDS, including selective COX-2 inhibitors, may result in deterioration of kidney function (eg, possible kidney failure). Monitor for signs of worsening renal function with concomitant use with NSAIDs.
  
  sparsentan will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Sparsentan (a CYP2C19 inducer) decreases exposure of CYP2C19 substrates and reduces efficacy related to these substrates. Serious - Use Alternative (1)omeprazole decreases effects of sparsentan by increasing gastric pH. Applies only to oral form of both agents. Avoid or Use Alternate Drug. Proton pump inhibitors may decrease sparsentan exposure which may reduce efficacy of sparsentan.

• spironolactone

  Monitor Closely (2)aspirin decreases effects of spironolactone by unspecified interaction mechanism. Use Caution/Monitor. When used concomitantly, spironolactone dose may need to be titrated to higher maintenance dose and the patient should be observed closely to determine if the desired effect is obtained.
  
  spironolactone and aspirin both increase serum potassium. Modify Therapy/Monitor Closely.

• St John's Wort

  Monitor Closely (1)St John's Wort will decrease the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• stiripentol

  Monitor Closely (2)stiripentol will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider reducing the dose of CYP2C19 substrates, if adverse reactions are experienced when administered concomitantly with stiripentol.
  
  stiripentol, omeprazole. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP3A4 inhibitor and inducer. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. CYP3A4 substrates may require dosage adjustment.Minor (1)aspirin will decrease the level or effect of stiripentol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

• streptomycin

  Minor (1)aspirin increases levels of streptomycin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• succinylcholine

  Monitor Closely (1)aspirin and succinylcholine both increase serum potassium. Use Caution/Monitor.

• sulfadiazine

  Minor (1)aspirin increases levels of sulfadiazine by unspecified interaction mechanism. Minor/Significance Unknown.

• sulfamethoxazole

  Monitor Closely (1)aspirin, sulfamethoxazole. Either increases effects of the other by plasma protein binding competition. Use Caution/Monitor. Due to high protein binding capacity of both drugs, one may displace the other when coadministered leading to an enhanced effect of the displaced drug; risk is low with low dose aspirin.Minor (1)omeprazole will increase the level or effect of sulfamethoxazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

• sulfasalazine

  Monitor Closely (2)aspirin and sulfasalazine both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and sulfasalazine both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of sulfasalazine by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• sulfisoxazole

  Minor (1)aspirin increases levels of sulfisoxazole by unspecified interaction mechanism. Minor/Significance Unknown.

• sulindac

  Monitor Closely (2)aspirin and sulindac both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and sulindac both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of sulindac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• tacrolimus

  Monitor Closely (1)omeprazole will increase the level or effect of tacrolimus by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Concomitant administration may increase tacrolimus whole blood concentrations, particularly in intermediate or poor metabolizers of CYP2C19

• tafluprost

  Monitor Closely (1)tafluprost, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• tamoxifen

  Monitor Closely (1)omeprazole will increase the level or effect of tamoxifen by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

• tazemetostat

  Monitor Closely (2)tazemetostat will decrease the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
  
  omeprazole will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• telmisartan

  Monitor Closely (3)telmisartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of telmisartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  telmisartan and aspirin both increase serum potassium. Use Caution/Monitor.

• temocillin

  Monitor Closely (2)temocillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  temocillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• tenecteplase

  Monitor Closely (1)aspirin, tenecteplase. Either increases toxicity of the other by anticoagulation. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• teniposide

  Minor (1)aspirin increases levels of teniposide by unspecified interaction mechanism. Minor/Significance Unknown.

• terazosin

  Monitor Closely (1)aspirin decreases effects of terazosin by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.

• terbutaline

  Monitor Closely (1)aspirin increases and terbutaline decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• theophylline

  Minor (2)omeprazole will decrease the level or effect of theophylline by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.
  
  omeprazole increases toxicity of theophylline by Other (see comment). Minor/Significance Unknown. Comment: Prolonged use of proton pump inhibitors can cause hypochlorhydria, which in turn causes peristalsis in small intestine to increase and peristalsis in the proximal colon to decrease; monitor for toxicity.

• thyroid desiccated

  Minor (1)omeprazole decreases levels of thyroid desiccated by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Conflicting evidence regarding this interaction exists.

• ticagrelor

  Monitor Closely (1)aspirin, ticagrelor. Other (see comment). Use Caution/Monitor. Comment: Maintenance doses of aspirin above 100 mg decreases effectiveness of ticagrelor. Therefore, after the initial loading dose of aspirin (usually 325 mg), use ticagrelor with a maintenance dose of aspirin of 75-100 mg.

• ticarcillin

  Monitor Closely (2)ticarcillin, aspirin. Either increases levels of the other by plasma protein binding competition. Use Caution/Monitor.
  
  ticarcillin, aspirin. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• ticlopidine

  Serious - Use Alternative (1)aspirin increases effects of ticlopidine by pharmacodynamic synergism. Avoid or Use Alternate Drug. Enhanced risk of hemorrhage.

• tiludronate

  Minor (1)aspirin decreases levels of tiludronate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• timolol

  Monitor Closely (2)aspirin decreases effects of timolol by pharmacodynamic antagonism. Use Caution/Monitor. Long term (>1 wk) NSAID use. NSAIDs decrease prostaglandin synthesis.
  
  timolol and aspirin both increase serum potassium. Use Caution/Monitor.

• tinidazole

  Monitor Closely (1)omeprazole will increase the level or effect of tinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

• tirofiban

  Monitor Closely (1)aspirin, tirofiban. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. The need for simultaneous use of low-dose aspirin and anticoagulant or antiplatelet agents are common for patients with cardiovascular disease; monitor closely.

• tizanidine

  Minor (1)omeprazole will decrease the level or effect of tizanidine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

• tobramycin

  Minor (1)aspirin increases levels of tobramycin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in preterm infants.

• tobramycin inhaled

  Monitor Closely (1)tobramycin inhaled and aspirin both increase nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Avoid concurrent or sequential use to decrease risk for ototoxicity

• tofacitinib

  Monitor Closely (1)omeprazole increases levels of tofacitinib by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. No specific dose adjustment recommended when tofacitinib coadministered with potent CYP2C19 inhibitors; decrease tofacitinib dose if coadministered with both moderate CYP3A4 and potent CYP2C19 inhibitors .

• tolazamide

  Monitor Closely (1)aspirin increases effects of tolazamide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.Minor (1)aspirin increases effects of tolazamide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• tolbutamide

  Monitor Closely (1)aspirin increases effects of tolbutamide by unknown mechanism. Use Caution/Monitor. Risk of hypoglycemia.Minor (2)omeprazole will increase the level or effect of tolbutamide by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.
  
  aspirin increases effects of tolbutamide by plasma protein binding competition. Minor/Significance Unknown. Large dose of salicylate.

• tolfenamic acid

  Monitor Closely (2)aspirin and tolfenamic acid both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and tolfenamic acid both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of tolfenamic acid by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• tolmetin

  Monitor Closely (2)aspirin and tolmetin both increase anticoagulation. Use Caution/Monitor.
  
  aspirin and tolmetin both increase serum potassium. Use Caution/Monitor.Minor (1)aspirin will increase the level or effect of tolmetin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• tolvaptan

  Monitor Closely (1)aspirin and tolvaptan both increase serum potassium. Use Caution/Monitor.

• torsemide

  Monitor Closely (1)aspirin increases and torsemide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• trandolapril

  Monitor Closely (1)trandolapril, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly with high dose aspirin, in elderly and volume depleted.Serious - Use Alternative (1)aspirin, trandolapril. pharmacodynamic antagonism. Avoid or Use Alternate Drug. Coadministration may result in a significant decrease in renal function. NSAIDs may diminish the antihypertensive effect of ACE inhibitors. The mechanism of these interactions is likely related to the ability of NSAIDs to reduce the synthesis of vasodilating renal prostaglandins.

• travoprost ophthalmic

  Monitor Closely (1)travoprost ophthalmic, aspirin. unspecified interaction mechanism. Use Caution/Monitor. There are conflicting reports from studies of either increased or decreased IOP when ophthalmic prostaglandins are coadministered with NSAIDs (either systemic or ophthalmic).

• trazodone

  Monitor Closely (1)trazodone, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• triamcinolone acetonide injectable suspension

  Monitor Closely (1)aspirin, triamcinolone acetonide injectable suspension. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Aspirin in conjunction with corticosteroids in hypoprothrombinemia should used with caution. Clearance of salicylates may increase with concurrent use of corticosteroids.Minor (1)triamcinolone acetonide injectable suspension decreases levels of aspirin by increasing renal clearance. Minor/Significance Unknown.

• triamterene

  Monitor Closely (1)triamterene and aspirin both increase serum potassium. Modify Therapy/Monitor Closely.Minor (2)triamterene, aspirin. Other (see comment). Minor/Significance Unknown. Comment: Risk of acute renal failure. Mechanism: NSAIDs decrease prostaglandin synthesis, which normally protect against nephrotoxicity.
  
  aspirin increases toxicity of triamterene by pharmacodynamic antagonism. Minor/Significance Unknown. NSAIDs decrease prostaglandin synthesis, increasing the risk of nephrotoxicity.

• triazolam

  Minor (1)omeprazole increases levels of triazolam by decreasing metabolism. Minor/Significance Unknown.

• triclabendazole

  Monitor Closely (1)triclabendazole will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

• tucatinib

  Serious - Use Alternative (1)tucatinib will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.

• valganciclovir

  Minor (1)aspirin will increase the level or effect of valganciclovir by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• valproic acid

  Monitor Closely (1)aspirin increases levels of valproic acid by plasma protein binding competition. Use Caution/Monitor.

• valsartan

  Monitor Closely (3)valsartan, aspirin. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: May result in renal function deterioration, particularly in elderly or volume depleted individuals.
  
  aspirin decreases effects of valsartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  valsartan and aspirin both increase serum potassium. Use Caution/Monitor.

• vancomycin

  Minor (1)aspirin increases levels of vancomycin by decreasing renal clearance. Minor/Significance Unknown. Interaction mainly occurs in neonates.

• varicella virus vaccine live

  Serious - Use Alternative (1)aspirin, varicella virus vaccine live. Mechanism: unspecified interaction mechanism. Avoid or Use Alternate Drug. Risk of Reye's Syndrome with combination; avoid salicylate use for 6 wks after vaccination.

• venlafaxine

  Monitor Closely (1)venlafaxine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

• verapamil

  Minor (1)verapamil increases effects of aspirin by unknown mechanism. Minor/Significance Unknown. Enhanced antiplatelet activity.

• vismodegib

  Monitor Closely (1)omeprazole will decrease the level or effect of vismodegib by Other (see comment). Use Caution/Monitor. Drugs that increase gastric pH alter vismodegib solubility and therefore reduce bioavailability; effect on efficacy unknown

• voclosporin

  Monitor Closely (1)voclosporin, aspirin. Either increases toxicity of the other by nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Coadministration with drugs associated with nephrotoxicity may increase the risk for acute and/or chronic nephrotoxicity.

• vorapaxar

  Monitor Closely (2)aspirin, vorapaxar. Either increases effects of the other by anticoagulation. Use Caution/Monitor. Coadministration of anticoagulants, antiplatelets, or other drug affecting coagulation should be monitored periodically due to potential increased risk of bleeding.
  
  aspirin, vorapaxar. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive antiplatelet effect may occur.

• voriconazole

  Monitor Closely (2)voriconazole will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.
  
  voriconazole will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Minor (1)omeprazole will increase the level or effect of voriconazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

• vortioxetine

  Monitor Closely (1)aspirin, vortioxetine. Either increases effects of the other by anticoagulation. Use Caution/Monitor. Risk minimal with low-dose aspirin.

• voxelotor

  Serious - Use Alternative (1)voxelotor will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.

• warfarin

  Monitor Closely (2)omeprazole will increase the level or effect of warfarin by Other (see comment). Use Caution/Monitor. Warfarin's less potent R-enantiomer is metabolized in part by CYP3A4 (and also CYP1A2 and CYP2C19). Monitor INR more frequently if coadministered with inhibitors of these isoenzymes and adjust warfarin dose if needed.
  
  aspirin increases effects of warfarin by anticoagulation. Modify Therapy/Monitor Closely. Avoid coadministration of chronic high-dose aspirin. Aspirin's antiplatelet properties may increase anticoagulation effect of warfarin. The need for simultaneous use of low-dose aspirin and warfarin is common for patients with cardiovascular disease. .

• willow bark

  Minor (2)aspirin will increase the level or effect of willow bark by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  willow bark increases effects of aspirin by pharmacodynamic synergism. Minor/Significance Unknown. Willow bark contains salicylic acid, which may have additive effects/toxicity with salicylate drugs.

• zafirlukast

  Minor (1)aspirin increases levels of zafirlukast by unknown mechanism. Minor/Significance Unknown.

• zanubrutinib

  Monitor Closely (1)aspirin, zanubrutinib. Either increases effects of the other by anticoagulation. Modify Therapy/Monitor Closely. Zanubrutinib-induced cytopenias increases risk of hemorrhage. Coadministration of zanubritinib with antiplatelets or anticoagulants may further increase this risk.

• zoledronic acid

  Minor (1)aspirin decreases levels of zoledronic acid by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• zotepine

  Monitor Closely (1)aspirin decreases effects of zotepine by pharmacodynamic antagonism. Use Caution/Monitor. NSAIDs decrease prostaglandin synthesis.