acetaminophen/aspirin/caffeine (OTC)

Brand and Other Names:Excedrin Extra Strength, Vanquish, more...Bayer Migraine Formula, Excedrin Migraine, Excedrin Menstrual Complete, Goody's Extra Strength Fast Pain Relief Powders, Goody's Extra Strength, Goody's Extra Strength Headache Powders, Goody's Migraine Relief, Anacin Advanced Headache, Arthriten, Pamprin Max
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Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

acetaminophen/aspirin/caffeine

tablet/capsule

  • 194mg/227mg/33mg
  • 250mg/250mg/65mg
  • 260mg/520mg/32.5mg
  • 325mg/500mg/65mg

Pain, Migraine

1-2 capsules or tablets PO q4-6hr PRN

Products vary; check specific labeling for each

Dosing Modifications

Severe renal impairment (CrCl <10 mL/min): Avoid use

Severe hepatic impairment: Avoid use

Safety and efficacy not established

Next:

Interactions

Interaction Checker

and acetaminophen/aspirin/caffeine

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            Contraindicated (5)

            • 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.

            • isocarboxazid

              isocarboxazid increases effects of caffeine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • linezolid

              linezolid increases effects of caffeine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • mifepristone

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

            • phenelzine

              phenelzine increases effects of caffeine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            Serious - Use Alternative (28)

            • abametapir

              abametapir will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. For 2 weeks after abametapir application, avoid taking drugs that are CYP1A2 substrates. If not feasible, avoid use of abametapir.

            • 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.

            • bupropion

              caffeine increases toxicity of bupropion by unspecified interaction mechanism. Avoid or Use Alternate Drug. May lower seizure threshold; keep bupropion dose as low as possible.

            • 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.

            • dipyridamole

              caffeine decreases effects of dipyridamole by pharmacodynamic antagonism. Contraindicated.

            • 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.

            • 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.

            • givosiran

              givosiran will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP1A2 substrates with givosiran. If unavoidable, decrease the CYP1A2 substrate dosage in accordance with approved product labeling.

            • 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.

            • iobenguane I 131

              caffeine will decrease the level or effect of iobenguane I 131 by Other (see comment). Avoid or Use Alternate Drug. Based on the mechanism of action of iobenguane, drugs that reduce catecholamine uptake or that deplete catecholamine stores may interfere with iobenguane uptake into cells, and thus, reduce iobenguane efficacy. Discontinue interfering drugs for at least 5 half-lives before administration of either the dosimetry or an iobenguane dose. Do not administer these drugs until at least 7 days after each iobenguane dose.

            • 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.

            • 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

              acetaminophen 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.

            • 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.

            • 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.

            • ozanimod

              ozanimod increases toxicity of caffeine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Because the active metabolite of ozanimod inhibits MAO-B in vitro, there is a potential for serious adverse reactions, including hypertensive crisis. Therefore, coadministration of ozanimod with drugs that can increase norepinephrine or serotonin is not recommended. Monitor for hypertension with concomitant use.

            • 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

              acetaminophen and pexidartinib both increase Other (see comment). Avoid or Use Alternate Drug. Pexidartinib can cause hepatotoxicity. Avoid coadministration of pexidartinib with other products know to cause hepatoxicity.

            • pretomanid

              acetaminophen, pretomanid. Either increases toxicity of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Pretomanid regimen associated with hepatotoxicity. Avoid alcohol and hepatotoxic agents, including herbal supplements and drugs other than bedaquiline and linezolid.

            • 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.

            Monitor Closely (438)

            • 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.

            • 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.

              albuterol and caffeine both decrease sedation. Use Caution/Monitor.

            • alfalfa

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

            • alfentanil

              alfentanil increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • alprazolam

              alprazolam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • amitriptyline

              amitriptyline increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • amobarbital

              amobarbital increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • amoxapine

              amoxapine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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

              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.

            • 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.

            • apalutamide

              apalutamide will decrease the level or effect of acetaminophen by increasing elimination. Use Caution/Monitor. Apalutamide induces UGT and may decrease systemic exposure of drugs that are UGT substrates.

            • 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.

              arformoterol and caffeine both decrease sedation. 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.

            • aripiprazole

              aripiprazole increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • armodafinil

              armodafinil and caffeine both decrease sedation. Use Caution/Monitor.

            • 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.

            • atogepant

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

            • avapritinib

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

            • axitinib

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

            • azelastine

              azelastine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • belladonna and opium

              belladonna and opium increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • bendroflumethiazide

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

            • benperidol

              benperidol increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • benzphetamine

              caffeine and benzphetamine both decrease sedation. 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.

            • 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.

            • brompheniramine

              brompheniramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • bupivacaine implant

              acetaminophen, bupivacaine implant. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Local anesthetics may increase the risk of developing methemoglobinemia when concurrently exposed to drugs that also cause methemoglobinemia.

            • buprenorphine buccal

              buprenorphine buccal increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • busulfan

              acetaminophen increases levels of busulfan by decreasing metabolism. Use Caution/Monitor. Use of acetaminophen prior to (< 72 hours) or concurrently with busulfan may result in decreased clearance of busulfan due to acetaminophen-induced decreases in glutathione levels.

            • butabarbital

              butabarbital increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • butalbital

              butalbital increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • butorphanol

              butorphanol increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • caplacizumab

              caplacizumab, aspirin. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor.

            • 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.

            • carbenoxolone

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

            • carbinoxamine

              carbinoxamine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • 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.

            • chloral hydrate

              chloral hydrate increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • chlordiazepoxide

              chlordiazepoxide increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • chlorothiazide

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

            • chlorpheniramine

              chlorpheniramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • chlorpromazine

              chlorpromazine increases and caffeine decreases sedation. 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.

            • cinnarizine

              cinnarizine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

              ciprofloxacin will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. The hepatic metabolism of caffeine may be decreased by ciprofloxacin; pharmacologic effects of caffeine may be increased.

            • citalopram

              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.

            • clemastine

              clemastine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • clobetasone

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

            • 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.

              clomipramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • clonazepam

              clonazepam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • clorazepate

              clorazepate increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • clozapine

              clozapine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • codeine

              codeine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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).

            • 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.

            • cyclizine

              cyclizine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • cyclopenthiazide

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

            • cyproheptadine

              cyproheptadine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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

            • 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.

            • dapsone topical

              acetaminophen increases toxicity of dapsone topical by altering metabolism. Modify Therapy/Monitor Closely. May induce methemoglobinemia .

            • deferasirox

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

              deferasirox increases levels of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • defibrotide

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

            • desipramine

              desipramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • dexchlorpheniramine

              dexchlorpheniramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • dexfenfluramine

              caffeine and dexfenfluramine both decrease sedation. Use Caution/Monitor.

            • dexmedetomidine

              dexmedetomidine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • dexmethylphenidate

              caffeine and dexmethylphenidate both decrease sedation. Use Caution/Monitor.

            • dextroamphetamine

              caffeine and dextroamphetamine both decrease sedation. Use Caution/Monitor.

            • dextromoramide

              dextromoramide increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • diamorphine

              diamorphine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • diethylpropion

              caffeine and diethylpropion both decrease sedation. Use Caution/Monitor.

            • difenoxin hcl

              difenoxin hcl increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • dimenhydrinate

              dimenhydrinate increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • diphenhydramine

              diphenhydramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • diphenoxylate hcl

              diphenoxylate hcl increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • dipipanone

              dipipanone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • dobutamine

              dobutamine and caffeine both decrease sedation. Use Caution/Monitor.

              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.

            • dopamine

              caffeine and dopamine both decrease sedation. Use Caution/Monitor.

            • dopexamine

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

              dopexamine and caffeine both decrease sedation. Use Caution/Monitor.

            • doxazosin

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

            • doxepin

              doxepin increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • droperidol

              droperidol increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • drospirenone

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

            • droxidopa

              caffeine and droxidopa both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. May increase risk for supine hypertension

            • 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.

            • eltrombopag

              eltrombopag increases levels of acetaminophen by decreasing metabolism. Use Caution/Monitor. UGT inhibition; significance of interaction unclear.

            • 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.

            • 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.

              ephedrine and caffeine both decrease sedation. Use Caution/Monitor.

            • epinephrine

              epinephrine and caffeine both decrease sedation. Use Caution/Monitor.

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

            • epinephrine inhaled

              caffeine, epinephrine inhaled. Either increases effects of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • epinephrine racemic

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

            • epinephrine racemic

              epinephrine racemic and caffeine both decrease sedation. 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

              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.

            • esketamine intranasal

              esketamine intranasal, caffeine. Either increases toxicity of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. Closely monitor blood pressure with concomitant use of esketamine nasal with stimulants. .

            • 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.

            • estazolam

              estazolam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • ethacrynic acid

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

            • ethanol

              ethanol increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • ethinylestradiol

              ethinylestradiol will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • etodolac

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

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

            • exenatide injectable solution

              exenatide injectable solution will decrease the level or effect of acetaminophen by unspecified interaction mechanism. Use Caution/Monitor. To avoid potential interaction, give acetaminophen at least 1 hour before or 4 hours after exenatide injection.

            • exenatide injectable suspension

              exenatide injectable suspension will decrease the level or effect of acetaminophen by unspecified interaction mechanism. Use Caution/Monitor. To avoid potential interaction, give acetaminophen at least 1 hour before or 4 hours after exenatide injection.

            • fenbufen

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

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

            • fenfluramine

              caffeine and fenfluramine both decrease sedation. 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.

            • feverfew

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

            • fexinidazole

              fexinidazole will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • finerenone

              acetaminophen 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 moderate 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

              acetaminophen 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.

            • 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.

            • fluphenazine

              fluphenazine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • flurazepam

              flurazepam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

              fluvoxamine will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • fondaparinux

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

            • formoterol

              formoterol and caffeine both decrease sedation. Use Caution/Monitor.

            • 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.

            • 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.

            • 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.

            • 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

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

            • green tea

              green tea increases effects of caffeine by Other (see comment). Use Caution/Monitor. Comment: Potential for increased risk of CNS stimulation due to caffeine component of green tea. Caution advised.

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

            • griseofulvin

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

            • guselkumab

              guselkumab, caffeine. Other (see comment). Use Caution/Monitor. Comment: Formation of CYP450 enzymes can be altered by increased levels of certain cytokines during chronic inflammation; thus, normalizing the formation of CYP450 enzymes. Upon initiation or discontinuation of guselkumab in patients who are receiving concomitant CYP450 substrates, particularly those with a narrow therapeutic index, consider monitoring for therapeutic effect.

            • haloperidol

              haloperidol increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • hydromorphone

              hydromorphone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • hydroxyzine

              hydroxyzine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • iloperidone

              iloperidone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • imatinib

              imatinib decreases levels of acetaminophen by decreasing hepatic clearance. Modify Therapy/Monitor Closely. In vitro, imatinib was found to inhibit acetaminophen O-glucuronidation (Ki value of 58.5 micro-M) at therapeutic levels; avoid chronic acetaminophen therapy with imatinib; if occasional acetaminophen administered, do not exceed 1300 mg/day.

              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

              imipramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • isavuconazonium sulfate

              acetaminophen will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 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.

            • isoniazid

              isoniazid will increase the level or effect of acetaminophen by affecting hepatic enzyme CYP2E1 metabolism. Use Caution/Monitor.

            • isoproterenol

              isoproterenol and caffeine both decrease sedation. Use Caution/Monitor.

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

            • ivacaftor

              acetaminophen increases levels of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor when coadministered with weak CYP3A4 inhibitors .

            • ketoprofen

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

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

            • ketotifen, ophthalmic

              ketotifen, ophthalmic increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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).

            • lemborexant

              acetaminophen 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 caffeine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • levalbuterol

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

              levalbuterol and caffeine both decrease sedation. 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.

            • levonorgestrel oral/ethinylestradiol/ferrous bisglycinate

              levonorgestrel oral/ethinylestradiol/ferrous bisglycinate will decrease the level or effect of acetaminophen by unknown mechanism. Use Caution/Monitor.

              acetaminophen increases levels of levonorgestrel oral/ethinylestradiol/ferrous bisglycinate by decreasing hepatic clearance. Use Caution/Monitor. Coadministration of ascorbic acid and certain combined hormonal contraceptives (CHCs) containing EE may increase plasma EE concentrations, possibly by inhibition of conjugation.

            • levorphanol

              levorphanol increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • levothyroxine

              caffeine decreases levels of levothyroxine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. COFFEE binds levothyroxine in the GI tract. Separate by 2 hours.

            • lisdexamfetamine

              caffeine and lisdexamfetamine both decrease sedation. Use Caution/Monitor.

            • 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.

            • lixisenatide

              lixisenatide will decrease the level or effect of acetaminophen by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. GLP1 agonists delay gastric emptying, which may affect absorption of concomitantly administered oral medications. No effects on acetaminophen Cmax and Tmax were observed when acetaminophen was administered 1 hr before lixisenatide. When administered 1 or 4 hr after lixisenatide, acetaminophen Cmax was decreased by 29% and 31% respectively and median Tmax was delayed by 2 and 1.75 hr, respectively.

            • lofepramine

              lofepramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • lofexidine

              lofexidine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • lomitapide

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

            • loprazolam

              loprazolam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • lorazepam

              lorazepam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • lormetazepam

              lormetazepam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • lornoxicam

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

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

            • losartan

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

              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.

            • loxapine

              loxapine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • loxapine inhaled

              loxapine inhaled increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • maprotiline

              maprotiline increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • marijuana

              marijuana increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

              melatonin increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • meloxicam

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

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

            • meperidine

              meperidine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • meprobamate

              meprobamate increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

              metaproterenol and caffeine both decrease sedation. Use Caution/Monitor.

            • methadone

              methadone increases and caffeine decreases sedation. 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.

            • methamphetamine

              caffeine and methamphetamine both decrease sedation. Use Caution/Monitor.

            • methotrexate

              caffeine decreases effects of methotrexate by pharmacodynamic antagonism. Use Caution/Monitor.

            • methyclothiazide

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

            • methylenedioxymethamphetamine

              caffeine and methylenedioxymethamphetamine both decrease sedation. Use Caution/Monitor.

            • methylphenidate

              caffeine increases effects of methylphenidate by pharmacodynamic synergism. Use Caution/Monitor. Risk of acute hypertensive episode.

            • 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

              midazolam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • midazolam intranasal

              acetaminophen 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.

            • midodrine

              caffeine and midodrine both decrease sedation. Use Caution/Monitor.

            • 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.

            • mipomersen

              mipomersen, acetaminophen. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Both drugs have potential to increase hepatic enzymes; monitor LFTs.

            • mirtazapine

              mirtazapine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • mistletoe

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

            • modafinil

              caffeine and modafinil both decrease sedation. 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.

            • morphine

              morphine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • motherwort

              motherwort increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • moxisylyte

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

            • moxonidine

              moxonidine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • mycophenolate

              aspirin will increase the level or effect of mycophenolate by acidic (anionic) drug competition for renal tubular clearance. Use Caution/Monitor.

            • nabilone

              nabilone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • nabumetone

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

              aspirin and nabumetone both increase serum potassium. 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.

            • nalbuphine

              nalbuphine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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

              norepinephrine and caffeine both decrease sedation. Use Caution/Monitor.

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

            • nortriptyline

              nortriptyline increases and caffeine decreases sedation. 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.

            • olanzapine

              olanzapine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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. .

            • opium tincture

              opium tincture increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • oxazepam

              oxazepam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • oxycodone

              oxycodone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • oxymorphone

              oxymorphone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • paliperidone

              paliperidone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • panax ginseng

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

            • papaveretum

              papaveretum increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • pefloxacin

              pefloxacin will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. 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.

            • pentazocine

              pentazocine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • pentobarbital

              pentobarbital increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • perphenazine

              perphenazine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • phendimetrazine

              caffeine and phendimetrazine both decrease sedation. Use Caution/Monitor.

            • phenindione

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

            • phenobarbital

              phenobarbital increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • phenoxybenzamine

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

            • phentermine

              caffeine and phentermine both decrease sedation. Use Caution/Monitor.

            • phentolamine

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

            • phenylephrine

              caffeine and phenylephrine both decrease sedation. Use Caution/Monitor.

            • phenylephrine PO

              caffeine and phenylephrine PO both decrease sedation. Use Caution/Monitor.

            • pholcodine

              pholcodine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • phytoestrogens

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

            • pimozide

              pimozide increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

              pirbuterol and caffeine both decrease sedation. Use Caution/Monitor.

            • piroxicam

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

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

            • primidone

              primidone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • 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.

            • prochlorperazine

              prochlorperazine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • promethazine

              promethazine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • propylhexedrine

              caffeine and propylhexedrine both decrease sedation. Use Caution/Monitor.

            • protamine

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

            • protriptyline

              protriptyline increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • quazepam

              quazepam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • quetiapine

              quetiapine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • rasagiline

              rasagiline increases effects of caffeine by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Risk of acute hypertensive episode.

            • 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.

            • risperidone

              risperidone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • rucaparib

              rucaparib will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP1A2 substrates, if clinically indicated.

            • 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.

              salmeterol and caffeine both decrease sedation. Use Caution/Monitor.

            • salsalate

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

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

            • scullcap

              scullcap increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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 increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • selegiline

              selegiline increases effects of caffeine by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Risk of acute hypertensive episode.

            • 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.

            • shepherd's purse

              shepherd's purse increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • solriamfetol

              caffeine and solriamfetol both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • 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.

            • 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, caffeine. affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP1A2 inhibitor and inducer. Monitor CYP1A2 substrates coadministered with stiripentol for increased or decreased effects. CYP1A2 substrates may require dosage adjustment.

            • succinylcholine

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

            • sufentanil

              sufentanil increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • 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).

            • tapentadol

              tapentadol increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • tazemetostat

              acetaminophen 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.

            • temazepam

              temazepam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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

              terbutaline and caffeine both decrease sedation. Use Caution/Monitor.

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

            • teriflunomide

              teriflunomide decreases levels of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • tetracaine

              tetracaine, acetaminophen. Other (see comment). Use Caution/Monitor. Comment: Monitor for signs of methemoglobinemia when methemoglobin-inducing drugs are coadministered.

            • 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.

            • thioridazine

              thioridazine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • thiothixene

              thiothixene increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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

              acetaminophen 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

            • 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.

            • topiramate

              topiramate increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

            • torsemide

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

            • tramadol

              tramadol increases and caffeine decreases sedation. 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.

              trazodone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • 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.

            • triazolam

              triazolam increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • triamterene

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

            • triclofos

              triclofos increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • trifluoperazine

              trifluoperazine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • trimipramine

              trimipramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • triprolidine

              triprolidine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • 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.

            • vortioxetine

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

            • warfarin

              warfarin and aspirin both increase anticoagulation. Modify Therapy/Monitor Closely. The need for simultaneous use of low-dose aspirin and warfarin are common for patients with cardiovascular disease; monitor closely.

              acetaminophen increases effects of warfarin by unknown mechanism. Use Caution/Monitor.

            • xylometazoline

              caffeine and xylometazoline both decrease sedation. Use Caution/Monitor.

            • yohimbine

              caffeine and yohimbine both decrease sedation. Use Caution/Monitor.

            • 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.

            • ziconotide

              ziconotide increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • ziprasidone

              ziprasidone increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • zotepine

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

            Minor (204)

            • 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 decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • acyclovir

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

            • adenosine

              caffeine decreases effects of adenosine by pharmacodynamic antagonism. Minor/Significance Unknown.

            • albiglutide

              albiglutide decreases levels of acetaminophen by unspecified interaction mechanism. Minor/Significance Unknown.

            • alendronate

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

            • 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).

            • amantadine

              amantadine, caffeine. Either increases effects of the other by pharmacodynamic synergism. Minor/Significance Unknown. Potential for additive CNS stimulation.

            • American ginseng

              American ginseng increases effects of caffeine by pharmacodynamic synergism. 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.

            • amobarbital

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

            • anamu

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

            • antithrombin alfa

              acetaminophen increases effects of antithrombin alfa by unknown mechanism. Minor/Significance Unknown.

            • antithrombin III

              acetaminophen increases effects of antithrombin III by unknown mechanism. Minor/Significance Unknown.

            • argatroban

              acetaminophen increases effects of argatroban by unknown mechanism. Minor/Significance Unknown.

            • armodafinil

              armodafinil will decrease the level or effect of caffeine by affecting hepatic enzyme CYP1A2 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.

            • balsalazide

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

            • bemiparin

              acetaminophen increases effects of bemiparin by unknown mechanism. 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.

            • bivalirudin

              acetaminophen increases effects of bivalirudin by unknown mechanism. Minor/Significance Unknown.

            • bumetanide

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

            • butabarbital

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

            • butalbital

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

            • calcium acetate

              caffeine decreases levels of calcium acetate by increasing renal clearance. Minor/Significance Unknown.

            • 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).

              caffeine decreases levels of calcium carbonate by increasing renal clearance. Minor/Significance Unknown.

            • calcium chloride

              caffeine decreases levels of calcium chloride by increasing renal clearance. Minor/Significance Unknown.

            • carbamazepine

              carbamazepine decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • cefadroxil

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

            • calcium citrate

              caffeine decreases levels of calcium citrate by increasing renal clearance. Minor/Significance Unknown.

            • calcium gluconate

              caffeine decreases levels of calcium gluconate by increasing renal clearance. Minor/Significance Unknown.

            • carbamazepine

              carbamazepine will decrease the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. 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.

            • 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.

            • cholestyramine

              cholestyramine decreases levels of acetaminophen by inhibition of GI absorption. Applies only to oral form of both agents. 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.

            • cigarette smoking

              cigarette smoking will decrease the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • cimetidine

              cimetidine will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • clonazepam

              clonazepam decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • clotrimazole

              clotrimazole increases levels of caffeine by decreasing metabolism. Minor/Significance Unknown.

            • colestipol

              colestipol decreases levels of acetaminophen by inhibition of GI absorption. Applies only to oral form of both agents. 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.

            • cyclopenthiazide

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

            • dalteparin

              acetaminophen increases effects of dalteparin by unknown mechanism. Minor/Significance Unknown.

            • danshen

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

            • 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.

            • dexamethasone

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

            • diazepam

              diazepam decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • 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.

            • disulfiram

              disulfiram will increase the level or effect of acetaminophen by affecting hepatic enzyme CYP2E1 metabolism. Minor/Significance Unknown.

            • enoxaparin

              acetaminophen increases effects of enoxaparin by unknown mechanism. Minor/Significance Unknown.

            • eplerenone

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

            • erythromycin base

              erythromycin base will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • erythromycin ethylsuccinate

              erythromycin ethylsuccinate will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • erythromycin lactobionate

              erythromycin lactobionate will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • erythromycin stearate

              erythromycin stearate will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • ethanol

              ethanol will decrease the level or effect of acetaminophen by affecting hepatic enzyme CYP2E1 metabolism. Minor/Significance Unknown.

              ethanol increases toxicity of acetaminophen by decreasing metabolism. Minor/Significance Unknown.

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

            • ethosuximide

              ethosuximide decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • etodolac

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

            • eucalyptus

              eucalyptus increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Minor/Significance Unknown.

            • felbamate

              felbamate decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • 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.

            • feverfew

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

            • fluconazole

              fluconazole increases levels of caffeine by decreasing metabolism. Minor/Significance Unknown.

            • fludrocortisone

              fludrocortisone decreases levels of aspirin by increasing renal clearance. 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.

            • folic acid

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

            • fondaparinux

              acetaminophen increases effects of fondaparinux by unknown mechanism. Minor/Significance Unknown.

            • fosphenytoin

              fosphenytoin decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • furosemide

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

            • gabapentin

              gabapentin decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • gabapentin enacarbil

              gabapentin enacarbil decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • 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.

            • glyburide

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

            • grapefruit

              grapefruit increases levels of caffeine by decreasing metabolism. Minor/Significance Unknown.

            • green tea

              green tea increases effects of acetaminophen by pharmacodynamic synergism. Minor/Significance Unknown. (Theoretical, due to caffeine content).

            • guarana

              guarana increases effects of caffeine by pharmacodynamic synergism. Minor/Significance Unknown.

            • heparin

              acetaminophen increases effects of heparin by unknown mechanism. 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.

            • isoniazid

              isoniazid will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

              isoniazid increases toxicity of acetaminophen by unknown mechanism. Minor/Significance Unknown.

            • itraconazole

              itraconazole increases levels of caffeine by decreasing metabolism. Minor/Significance Unknown.

            • lacosamide

              lacosamide decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • ketoconazole

              ketoconazole increases levels of caffeine by decreasing metabolism. 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.

            • lamotrigine

              lamotrigine decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • levetiracetam

              levetiracetam decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • liraglutide

              liraglutide decreases levels of acetaminophen by unspecified interaction mechanism. Minor/Significance Unknown.

            • lorazepam

              lorazepam decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • lornoxicam

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

            • methsuximide

              methsuximide decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • 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.

            • metoclopramide

              metoclopramide increases levels of acetaminophen by enhancing GI absorption. Applies only to oral form of both agents. 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.

            • metronidazole

              metronidazole will increase the level or effect of acetaminophen by affecting hepatic enzyme CYP2E1 metabolism. Minor/Significance Unknown.

            • mexiletine

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

            • miconazole vaginal

              miconazole vaginal increases levels of caffeine by decreasing metabolism. Minor/Significance Unknown.

            • modafinil

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

            • 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.

            • oxaprozin

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

            • oxcarbazepine

              oxcarbazepine decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • oxybutynin

              oxybutynin decreases levels of acetaminophen by unspecified interaction mechanism. Minor/Significance Unknown.

            • oxybutynin topical

              oxybutynin topical decreases levels of acetaminophen by unspecified interaction mechanism. Minor/Significance Unknown.

            • oxybutynin transdermal

              oxybutynin transdermal decreases levels of acetaminophen by unspecified interaction mechanism. 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.

            • peginterferon alfa 2a

              peginterferon alfa 2a will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • 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.

            • pentobarbital

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

            • phenindione

              acetaminophen increases effects of phenindione by unknown mechanism. Minor/Significance Unknown.

            • phenobarbital

              phenobarbital decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

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

            • phenytoin

              phenytoin decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • pipemidic acid

              pipemidic acid will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. 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.

            • posaconazole

              posaconazole increases levels of caffeine by decreasing metabolism. 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.

            • primidone

              primidone decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

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

            • protamine

              acetaminophen increases effects of protamine by unknown mechanism. Minor/Significance Unknown.

            • rifampin

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

            • rifabutin

              rifabutin decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • rifampin

              rifampin decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • 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.

            • rufinamide

              rufinamide decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • ruxolitinib

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

            • sage

              sage increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. 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.

            • secobarbital

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

            • smoking

              smoking will decrease the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. 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.

            • 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.

            • thiamine

              caffeine decreases levels of thiamine by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown. Coffee, tea are high in anti-thiamine factors.

            • tiagabine

              tiagabine decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • tiludronate

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

            • tobacco use

              tobacco use will decrease the level or effect of caffeine 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

              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.

            • tolmetin

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

            • topiramate

              topiramate decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • 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.

            • valproic acid

              valproic acid decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism incr levels of hepatotoxic metabolites.

            • 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.

              verapamil will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • voriconazole

              voriconazole increases levels of caffeine by decreasing 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.

            • yerba mate

              yerba mate increases effects of caffeine by pharmacodynamic synergism. Minor/Significance Unknown.

            • zafirlukast

              aspirin increases levels of zafirlukast by unknown mechanism. Minor/Significance Unknown.

            • zileuton

              zileuton will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

            • zoledronic acid

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

            • zonisamide

              zonisamide decreases levels of acetaminophen by increasing metabolism. Minor/Significance Unknown. Enhanced metabolism increase levels of hepatotoxic metabolites.

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            Adverse Effects

            Frequency Not Defined

            Acetaminophen

            • Angioedema, laryngeal edema
            • Pruritic maculopapular rash, urticaria
            • Agranulocytosis, leukopenia, neutropenia, pancytopenia, thrombocytopenia, thrombocytopenic purpura
            • Hepatotoxicity
            • Anaphylactoid reaction

            Aspirin

            • Rash, urticaria
            • Dyspepsia, heartburn, nausea, stomach pain, vomiting
            • Tinnitus (high dose or long-term use)

            Caffeine

            • Palpitations (dose dependent), tachycardia
            • Insomnia, restlessness, nervousness, tremor, irritability
            • Diarrhea, nausea, vomiting
            • Diuresis
            • Tinnitus
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            Warnings

            Contraindications

            Hypersensitivity

            Hepatitis or severe hepatic or renal impairment

            Repeated administration in patients with anemia or with cardiac, pulmonary, or renal disease

            Cautions

            Risk of hepatotoxicity (higher in alcoholics and with use of >1 acetaminophen-containing product)

            If pregnant or breast-feeding, ask a health professional before use; it is especially important not to use ibuprofen at 20 weeks or later in pregnancy unless definitely directed to do so by a doctor; may cause problems in the unborn child or complications during delivery

            Glucose-6-phosphate dehydrogenase (G6PD) deficiency

            Gastrointestinal (GI) bleeding; exercise particular caution in patients with history of GI bleeding, alcoholism, or bleeding disorders

            Avoid with active peptic ulcer disease

            Avoid with severe renal impairment (ie, CrCl <10 mL/min)

            Avoid with severe hepatic impairment

            Acetaminophen: Risk for rare, but serious skin reactions that can be fatal; these reactions include Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP); symptoms may include skin redness, blisters and rash

            Headaches may worsen if this product is used for ≥10 days per month (ie, medication overuse headache)

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            Pregnancy & Lactation

            Pregnancy

            Avoid chronic or intermittent high doses of aspirin during pregnancy; may affect maternal and newborn hemostasis mechanisms, leading to an increased risk of hemorrhage

            High doses of aspirin may also increase perinatal mortality by intrauterine growth restriction and teratogenic effects

            Near term, aspirin may prolong gestation and labor

            Premature closure of the ductus arteriosus may occur if used near term with use of full-dose aspirin

            Seek advice of health professional before using OTC drugs during pregnancy

            Lactation

            Drug enters breast milk; a decision should be made regarding whether to discontinue nursing or to discontinue drug, taking into account importance of drug to mother

            Seek advice of health professional before using OTC drugs while breastfeeding

            Pregnancy Categories

            A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA: Information not available.

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            Pharmacology

            Mechanism of Action

            Acetaminophen: Acts on hypothalamus to produce antipyresis

            Aspirin: Acts on hypothalamus to produce antipyresis; anti-inflammatory properties are attributed to inhibition of prostaglandin synthetase, resulting in decreased formation of thromboxane A2

            Caffeine: Vasoconstrictive properties may be helpful in treatment of vascular headaches

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            Images

            No images available for this drug.
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            Patient Handout

            A Patient Handout is not currently available for this monograph.
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            Medscape prescription drug monographs are based on FDA-approved labeling information, unless otherwise noted, combined with additional data derived from primary medical literature.