irbesartan/hydrochlorothiazide (Rx)

Hypertension

150 mg/12.5 mg PO qDay initially; if needed, after 1-2 weeks may titrate up to 300 mg/25 mg PO qDay

Hepatic impairment

• No dosage adjustment necessary in patients with hepatic impairment

Renal impairment

• Usual regimens of therapy may be followed as long as the patient’s creatinine clearance is >30 mL/min; in patients with more severe renal impairment, loop diuretics are preferred to thiazides, so this drug combination is not recommended

Dosing considerations

Not recommended as initial therapy in patients with intravascular volume depletion

Maximum antihypertensive effects are attained within 2-4 weeks after change in dose

In patients not controlled on monotherapy with irbesartan or hydrochlorothiazide, recommended doses of this drug combination, in order of increasing mean effect, are (irbesartan and hydrochlorothiazide) 150/12.5 mg, 300/12.5 mg, and 300/25 mg; the largest incremental effect will likely be in the transition from monotherapy to 150/12.5 mg

Safety and efficacy not established

Contraindicated (2)

• aliskiren

  irbesartan decreases effects of aliskiren by Other (see comment). Contraindicated. Comment: Aliskiren use contraindicated with ARBs in patients with diabetes; avoid coadministration with ARBs if GFR. In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, coadministration of ARBS 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.

• sparsentan

  sparsentan, irbesartan. Either increases toxicity of the other by pharmacodynamic synergism. Contraindicated. Coadministration of ARBs with sparsentan is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function (eg, acute renal failure).

Serious - Use Alternative (28)

• aminolevulinic acid oral

  aminolevulinic acid oral, hydrochlorothiazide. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid administering other phototoxic drugs with aminolevulinic acid oral for 24 hr during perioperative period.

• aminolevulinic acid topical

  hydrochlorothiazide increases toxicity of aminolevulinic acid topical by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration of photosensitizing drugs may enhance the phototoxic reaction to photodynamic therapy with aminolevulinic acid.

• baricitinib

  irbesartan will increase the level or effect of baricitinib by decreasing elimination. Avoid or Use Alternate Drug. Coadministration of baricitinib with strong organic anion transporter 3 (OAT3) inhibitors is not recommended.

• benazepril

  irbesartan, benazepril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• captopril

  irbesartan, captopril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• carbamazepine

  carbamazepine, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased risk of systemic hyponatremia.

• cyclophosphamide

  hydrochlorothiazide increases toxicity of cyclophosphamide by decreasing renal clearance. Avoid or Use Alternate Drug. Increased myelosuppressive effects.

• cyclosporine

  cyclosporine, hydrochlorothiazide. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased risk of systemic hyponatremia.

• dofetilide

  hydrochlorothiazide increases levels of dofetilide by decreasing renal clearance. Contraindicated. Risk of prolonged QTc interval.

• enalapril

  irbesartan, enalapril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• erdafitinib

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

• fosinopril

  irbesartan, fosinopril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• isocarboxazid

  isocarboxazid, hydrochlorothiazide. Other (see comment). Contraindicated. Comment: Additive hypotensive effects may be seen when MAOI's are combined with antihypertensives.

• lisinopril

  irbesartan, lisinopril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• lithium

  irbesartan increases toxicity of lithium by decreasing renal clearance. Avoid or Use Alternate Drug.

• lofexidine

  lofexidine, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration with other drugs that decrease pulse or blood pressure to mitigate risk of excessive bradycardia and hypotension.
  
  lofexidine, irbesartan. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration with other drugs that decrease pulse or blood pressure to mitigate risk of excessive bradycardia and hypotension.

• lonafarnib

  irbesartan 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.

• methyl aminolevulinate

  hydrochlorothiazide, methyl aminolevulinate. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Each drug may increase the photosensitizing effect of the other.

• moexipril

  irbesartan, moexipril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• perindopril

  irbesartan, perindopril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• quinapril

  irbesartan, quinapril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• ramipril

  irbesartan, ramipril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• siponimod

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

• squill

  hydrochlorothiazide increases toxicity of squill by Other (see comment). Avoid or Use Alternate Drug. Comment: Potassium depletion may enhance toxicity of squill.

• trandolapril

  irbesartan, trandolapril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• tretinoin

  hydrochlorothiazide, tretinoin. Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased phototoxicity.

• tretinoin topical

  hydrochlorothiazide, tretinoin topical. Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased phototoxicity.

• tucatinib

  irbesartan will increase the level or effect of tucatinib by Other (see comment). Avoid or Use Alternate Drug. Coadministration of tucatinib (a CYP2C8 substrate) with a strong or moderate CYP2C8 inhibitors increases tucatinib plasma concentrations and risk of toxicities.

Monitor Closely (234)

• acebutolol

  irbesartan and acebutolol both increase serum potassium. Use Caution/Monitor.
  
  acebutolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  acebutolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• aceclofenac

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

• acemetacin

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

• albiglutide

  irbesartan increases effects of albiglutide by Other (see comment). Use Caution/Monitor. Comment: Angiotensin II receptor antagonists may enhance hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Monitor patients for changes in glycemic control.
  
  hydrochlorothiazide decreases effects of albiglutide by pharmacodynamic antagonism. Use Caution/Monitor. Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Monitor glycemic control especially when initiating, discontinuing, or increasing thiazide diuretic dose.

• albuterol

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

• aldesleukin

  aldesleukin increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
  
  aldesleukin increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• aliskiren

  irbesartan decreases levels of aliskiren by unspecified interaction mechanism. Use Caution/Monitor.

• amifostine

  amifostine, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration with blood pressure lowering agents may increase the risk and severity of hypotension associated with amifostine. When amifostine is used at chemotherapeutic doses, withhold blood pressure lowering medications for 24 hr prior to amifostine; if blood pressure lowering medication cannot be withheld, do not administer amifostine.

• amifostine

  amifostine, irbesartan. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration with blood pressure lowering agents may increase the risk and severity of hypotension associated with amifostine. When amifostine is used at chemotherapeutic doses, withhold blood pressure lowering medications for 24 hr prior to amifostine; if blood pressure lowering medication cannot be withheld, do not administer amifostine.

• amiloride

  irbesartan and amiloride both increase serum potassium. Modify Therapy/Monitor Closely.
  
  amiloride increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

• amiodarone

  amiodarone will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• aspirin

  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.

• amoxicillin

  amoxicillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• arformoterol

  arformoterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• aspirin

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

• aspirin rectal

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

• aspirin/citric acid/sodium bicarbonate

  irbesartan, aspirin/citric acid/sodium bicarbonate. 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.
  
  irbesartan and aspirin/citric acid/sodium bicarbonate both increase serum potassium. Use Caution/Monitor.
  
  aspirin/citric acid/sodium bicarbonate 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.
  
  aspirin/citric acid/sodium bicarbonate increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• atenolol

  atenolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and atenolol both increase serum potassium. Use Caution/Monitor.
  
  atenolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• atogepant

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

• avanafil

  avanafil increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• avanafil

  avanafil increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• axitinib

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

• beclomethasone, inhaled

  beclomethasone, inhaled increases toxicity of hydrochlorothiazide by increasing elimination. Use Caution/Monitor. May increase the hypokalemic effects of thiazide diuretics.

• benazepril

  benazepril increases toxicity of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Enhanced hypotensive effects; increased risk of nephrotoxicity.

• bendroflumethiazide

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

• betaxolol

  irbesartan and betaxolol both increase serum potassium. Use Caution/Monitor.
  
  betaxolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  betaxolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• bisoprolol

  bisoprolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  bisoprolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and bisoprolol both increase serum potassium. Use Caution/Monitor.

• bretylium

  hydrochlorothiazide, bretylium. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Each drug may cause hypotension.
  
  irbesartan, bretylium. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Each drug may cause hypotension.

• brimonidine

  brimonidine increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor.

• bumetanide

  bumetanide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• bumetanide

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

• buprenorphine, long-acting injection

  buprenorphine, long-acting injection decreases effects of hydrochlorothiazide by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Opioids can reduce diuretic efficacy by inducing antidiuretic hormone release.

• calcifediol

  hydrochlorothiazide increases toxicity of calcifediol by Other (see comment). Use Caution/Monitor. Comment: Thiazide diuretics may increase serum calcium by decreasing urinary calcium excretion.

• canagliflozin

  irbesartan and canagliflozin both increase serum potassium. Use Caution/Monitor.

• candesartan

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

• captopril

  captopril, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs lower blood pressure. Increased risk of nephrotoxicity. Monitor blood pressure and renal function.

• carbenoxolone

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

• carbidopa

  carbidopa increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.
  
  carbidopa increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

• carvedilol

  carvedilol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and carvedilol both increase serum potassium. Use Caution/Monitor.
  
  carvedilol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• cefprozil

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

• celecoxib

  irbesartan and celecoxib both increase serum potassium. Use Caution/Monitor.
  
  celecoxib 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, celecoxib. 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.

• celecoxib

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

• celiprolol

  celiprolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  celiprolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and celiprolol both increase serum potassium. Use Caution/Monitor.
  
  hydrochlorothiazide decreases levels of celiprolol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

• chlorothiazide

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

• chlorthalidone

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

• cholestyramine

  cholestyramine decreases levels of hydrochlorothiazide by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

• choline magnesium trisalicylate

  irbesartan and choline magnesium trisalicylate both increase serum potassium. Use Caution/Monitor.
  
  choline magnesium trisalicylate 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, choline magnesium trisalicylate. 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.

• citalopram

  hydrochlorothiazide, citalopram. pharmacodynamic synergism. Use Caution/Monitor. Possible additive hyponatremia.

• cornsilk

  cornsilk increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of hypokalemia (theoretical interaction).

• corticotropin

  corticotropin increases toxicity of hydrochlorothiazide by increasing renal clearance. Use Caution/Monitor. May enhance hypokalemic effect of thiazide diuretics.

• cyclopenthiazide

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

• cyclosporine

  cyclosporine increases toxicity of hydrochlorothiazide by unspecified interaction mechanism. Use Caution/Monitor. Coadministration of hydrochlorothiazide with cyclosporine may increase the risk of hypermagnesemia, hyperuricemia, and possible nephrotoxicity.

• dalteparin

  dalteparin increases toxicity of irbesartan by Other (see comment). Use Caution/Monitor. Comment: Low molecular weight heparins may suppress adrenal aldosterone secretion, which can potentially cause hyperkalemia.

• daprodustat

  irbesartan will increase the level or effect of daprodustat by Other (see comment). Modify Therapy/Monitor Closely. Moderate CYP2C8 inhibitors increase daprodustat exposure. If coadministered with moderate CYP2C8 inhibitors, reduce daprodustat starting dose by half (except if starting dose is already 1 mg). Monitor hemoglobin and adjust daprodustat dose when initiating or stopping therapy with moderate CYP2C8 inhibitors during treatment

• deflazacort

  hydrochlorothiazide and deflazacort both decrease serum potassium. Use Caution/Monitor.

• diazoxide

  hydrochlorothiazide increases toxicity of diazoxide by unspecified interaction mechanism. Use Caution/Monitor. May enhance hyperglycemic effects of diazoxide.

• dichlorphenamide

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

• diclofenac

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

• dicloxacillin

  dicloxacillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• diflunisal

  irbesartan and diflunisal both increase serum potassium. Use Caution/Monitor.
  
  diflunisal 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, diflunisal. 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.

• diflunisal

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

• digoxin

  hydrochlorothiazide increases effects of digoxin by pharmacodynamic synergism. Use Caution/Monitor. Hypokalemia increases digoxin effects.
  
  digoxin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and digoxin both increase serum potassium. Use Caution/Monitor.
  
  digoxin will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• dobutamine

  dobutamine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• dopexamine

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

• dofetilide

  dofetilide will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• dopexamine

  dopexamine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• drospirenone

  drospirenone increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.
  
  irbesartan and drospirenone both increase serum potassium. Modify Therapy/Monitor Closely.

• empagliflozin

  empagliflozin, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration of empagliflozin with diuretics results in increased urine volume and frequency of voids, which might enhance the potential for volume depletion.

• enoxaparin

  enoxaparin increases toxicity of irbesartan by Other (see comment). Use Caution/Monitor. Comment: Low molecular weight heparins may suppress adrenal aldosterone secretion, which can potentially cause hyperkalemia.

• ephedrine

  ephedrine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• epinephrine

  epinephrine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• epinephrine racemic

  epinephrine racemic and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• eplerenone

  irbesartan, eplerenone. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of hyperkalemia.

• eprosartan

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

• esmolol

  irbesartan and esmolol both increase serum potassium. Use Caution/Monitor.
  
  esmolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  esmolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• ethacrynic acid

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

• etodolac

  etodolac increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, etodolac. 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.
  
  etodolac decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and etodolac both increase serum potassium. Use Caution/Monitor.

• exenatide injectable solution

  irbesartan increases effects of exenatide injectable solution by Other (see comment). Use Caution/Monitor. Comment: Angiotensin II receptor antagonists may enhance hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Monitor patients for changes in glycemic control.
  
  hydrochlorothiazide decreases effects of exenatide injectable solution by pharmacodynamic antagonism. Use Caution/Monitor. Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Monitor glycemic control especially when initiating, discontinuing, or increasing thiazide diuretic dose.

• exenatide injectable suspension

  irbesartan increases effects of exenatide injectable suspension by Other (see comment). Use Caution/Monitor. Comment: Angiotensin II receptor antagonists may enhance hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Monitor patients for changes in glycemic control.
  
  hydrochlorothiazide decreases effects of exenatide injectable suspension by pharmacodynamic antagonism. Use Caution/Monitor. Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Monitor glycemic control especially when initiating, discontinuing, or increasing thiazide diuretic dose.

• fenbufen

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

• fenoprofen

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

• fenoprofen

  irbesartan and fenoprofen both increase serum potassium. Use Caution/Monitor.
  
  fenoprofen 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, fenoprofen. 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.

• fentanyl

  fentanyl decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• fentanyl intranasal

  fentanyl intranasal decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• fentanyl transdermal

  fentanyl transdermal decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• fentanyl transmucosal

  fentanyl transmucosal decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• finerenone

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

• flibanserin

  irbesartan 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.

• flurbiprofen

  irbesartan, flurbiprofen. 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.
  
  flurbiprofen increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  flurbiprofen decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and flurbiprofen both increase serum potassium. Use Caution/Monitor.

• formoterol

  formoterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• furosemide

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

• furosemide

  furosemide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• gentamicin

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

• heparin

  heparin increases toxicity of irbesartan by Other (see comment). Use Caution/Monitor. Comment: Low molecular weight heparins may suppress adrenal aldosterone secretion, which can potentially cause hyperkalemia.

• ibuprofen

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

• hydrochlorothiazide

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

• ibuprofen

  irbesartan and ibuprofen both increase serum potassium. Use Caution/Monitor.
  
  ibuprofen decreases effects of irbesartan by pharmacodynamic antagonism. Use Caution/Monitor. Antihypertensive effect of angiotensin receptor blockers may be attenuated by NSAIDs; monitor renal function and blood pressure periodically.
  
  irbesartan, ibuprofen. 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.

• ibuprofen IV

  irbesartan, ibuprofen IV. 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.
  
  irbesartan and ibuprofen IV both increase serum potassium. Use Caution/Monitor.
  
  ibuprofen IV decreases effects of irbesartan by pharmacodynamic antagonism. Use Caution/Monitor. Antihypertensive effect of angiotensin receptor blockers may be attenuated by NSAIDs; monitor renal function and blood pressure periodically.
  
  hydrochlorothiazide will increase the level or effect of ibuprofen IV by acidic (anionic) drug competition for renal tubular clearance. Use Caution/Monitor.
  
  ibuprofen IV increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor. NSAIDs may decrease the therapeutic effects of thiazide-like diuretics; may also enhance nephrotoxic effects.

• indacaterol, inhaled

  hydrochlorothiazide, indacaterol, inhaled. serum potassium. Use Caution/Monitor. Combination may increase risk of hypokalemia.
  
  indacaterol, inhaled, hydrochlorothiazide. Other (see comment). Use Caution/Monitor. Comment: Caution is advised in the coadministration of indacaterol neohaler with non-potassium-sparing diuretics.

• indapamide

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

• indapamide

  hydrochlorothiazide and indapamide both decrease serum potassium. Use Caution/Monitor.

• indomethacin

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

• insulin aspart

  irbesartan increases effects of insulin aspart by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin degludec

  hydrochlorothiazide decreases effects of insulin degludec by Other (see comment). Use Caution/Monitor. Comment: Diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, possibly by diuretic-induced hpokalemia.

• insulin aspart protamine/insulin aspart

  irbesartan increases effects of insulin aspart protamine/insulin aspart by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin degludec

  irbesartan, insulin degludec. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.
  
  irbesartan increases effects of insulin degludec by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin degludec/insulin aspart

  irbesartan, insulin degludec/insulin aspart. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.
  
  hydrochlorothiazide decreases effects of insulin degludec/insulin aspart by Other (see comment). Use Caution/Monitor. Comment: Diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, possibly by diuretic-induced hpokalemia.

• insulin detemir

  irbesartan increases effects of insulin detemir by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin inhaled

  hydrochlorothiazide decreases effects of insulin inhaled by Other (see comment). Use Caution/Monitor. Comment: Diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, possibly by diuretic-induced hpokalemia.

• insulin glargine

  irbesartan increases effects of insulin glargine by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin glulisine

  irbesartan increases effects of insulin glulisine by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin inhaled

  irbesartan, insulin inhaled. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.
  
  irbesartan increases effects of insulin inhaled by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin isophane human/insulin regular human

  irbesartan increases effects of insulin isophane human/insulin regular human by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin lispro

  irbesartan increases effects of insulin lispro by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin lispro protamine/insulin lispro

  irbesartan increases effects of insulin lispro protamine/insulin lispro by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin NPH

  irbesartan increases effects of insulin NPH by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin regular human

  irbesartan increases effects of insulin regular human by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• irbesartan

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

• isavuconazonium sulfate

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

• isoproterenol

  isoproterenol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• ivacaftor

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

• juniper

  juniper, hydrochlorothiazide. Other (see comment). Use Caution/Monitor. Comment: Juniper may potentiate or interfere with diuretic therapy. Juniper has diuretic effects, but may cause kidney damage at large doses.

• ketoprofen

  ketoprofen increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  ketoprofen decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and ketoprofen both increase serum potassium. Use Caution/Monitor.
  
  irbesartan, ketoprofen. 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.

• ketorolac

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

• ketorolac intranasal

  ketorolac intranasal decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and ketorolac intranasal both increase serum potassium. Use Caution/Monitor.
  
  ketorolac intranasal increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor. .
  
  irbesartan, ketorolac intranasal. 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.

• labetalol

  irbesartan and labetalol both increase serum potassium. Use Caution/Monitor.
  
  labetalol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  labetalol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• lemborexant

  irbesartan 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.

• levalbuterol

  levalbuterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• levodopa

  levodopa increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.
  
  levodopa increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

• lily of the valley

  hydrochlorothiazide increases toxicity of lily of the valley by Other (see comment). Use Caution/Monitor. Comment: Increased risk of cardiac toxicity due to K+ depletion.

• liraglutide

  irbesartan increases effects of liraglutide by Other (see comment). Use Caution/Monitor. Comment: Angiotensin II receptor antagonists may enhance hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Monitor patients for changes in glycemic control.

• liraglutide

  hydrochlorothiazide decreases effects of liraglutide by pharmacodynamic antagonism. Use Caution/Monitor. Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Monitor glycemic control especially when initiating, discontinuing, or increasing thiazide diuretic dose.

• lithium

  hydrochlorothiazide increases toxicity of lithium by decreasing elimination. Use Caution/Monitor.

• lomitapide

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

• lornoxicam

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

• losartan

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

• maitake

  maitake increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor.

• lurasidone

  lurasidone increases effects of hydrochlorothiazide by Other (see comment). Use Caution/Monitor. Comment: Potential for increased risk of hypotension with concurrent use. Monitor blood pressure and adjust dose of antihypertensive agent as needed.

• maitake

  maitake increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of hypokalemia (theoretical interaction).

• maraviroc

  maraviroc, irbesartan. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.

• meclofenamate

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

• mefenamic acid

  mefenamic acid 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.
  
  mefenamic acid increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and mefenamic acid both increase serum potassium. Use Caution/Monitor.
  
  irbesartan, mefenamic acid. 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.

• meloxicam

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

• metaproterenol

  metaproterenol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• methyclothiazide

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

• methoxsalen

  methoxsalen, hydrochlorothiazide. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive photosensitizing effects.

• methylphenidate

  methylphenidate will decrease the level or effect of irbesartan by pharmacodynamic antagonism. Use Caution/Monitor. Methylphenidate may diminish antihypertensive effects. Monitor BP.

• methylphenidate transdermal

  methylphenidate transdermal decreases effects of hydrochlorothiazide by anti-hypertensive channel blocking. Use Caution/Monitor.
  
  methylphenidate transdermal decreases effects of irbesartan by anti-hypertensive channel blocking. Use Caution/Monitor.

• metolazone

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

• metoprolol

  hydrochlorothiazide, metoprolol. Either increases toxicity of the other by Other (see comment). Modify Therapy/Monitor Closely. Comment: May cause idiosyncratic reaction, resulting in acute transient myopia and acute angle-closure glaucoma, which can lead to permanent vision loss.
  
  irbesartan and metoprolol both increase serum potassium. Use Caution/Monitor.
  
  metoprolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  metoprolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• midazolam intranasal

  irbesartan 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.

• mometasone inhaled

  mometasone inhaled increases toxicity of hydrochlorothiazide by Other (see comment). Use Caution/Monitor. Comment: Corticosteroids may increase hypokalemic effect of loop diuretics.

• mycophenolate

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

• nabumetone

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

• nadolol

  irbesartan and nadolol both increase serum potassium. Use Caution/Monitor.
  
  nadolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  nadolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• nafcillin

  nafcillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• naproxen

  irbesartan and naproxen both increase serum potassium. Use Caution/Monitor.
  
  naproxen 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, naproxen. 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.

• naproxen

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

• nebivolol

  nebivolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and nebivolol both increase serum potassium. Use Caution/Monitor.
  
  nebivolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• nitroglycerin rectal

  nitroglycerin rectal, irbesartan. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Observe for possible additive hypotensive effects during concomitant use. .
  
  nitroglycerin rectal, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Observe for possible additive hypotensive effects during concomitant use. .

• norepinephrine

  norepinephrine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• oxaprozin

  irbesartan and oxaprozin both increase serum potassium. Use Caution/Monitor.
  
  oxaprozin 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, oxaprozin. 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.

• oliceridine

  oliceridine decreases effects of hydrochlorothiazide by Other (see comment). Use Caution/Monitor. Comment: Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Monitor for signs of diminished diuresis and/or effects on blood pressure and increase dosage of the diuretic as needed. .

• olmesartan

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

• olodaterol inhaled

  hydrochlorothiazide and olodaterol inhaled both decrease serum potassium. Use Caution/Monitor.

• oxaprozin

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

• paclitaxel

  irbesartan will increase the level or effect of paclitaxel by Other (see comment). Use Caution/Monitor. Paclitaxel levels/toxicity may increase when coadministered with CYP2C8 inhibitors

• paclitaxel protein bound

  irbesartan will increase the level or effect of paclitaxel protein bound by Other (see comment). Use Caution/Monitor. Paclitaxel levels/toxicity may increase when coadministered with CYP2C8 inhibitors

• parecoxib

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

• penbutolol

  penbutolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and penbutolol both increase serum potassium. Use Caution/Monitor.
  
  penbutolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• penicillin G aqueous

  penicillin G aqueous, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• pindolol

  irbesartan and pindolol both increase serum potassium. Use Caution/Monitor.
  
  pindolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• pindolol

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

• pirbuterol

  pirbuterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• piroxicam

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

• pivmecillinam

  pivmecillinam, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• potassium acid phosphate

  irbesartan and potassium acid phosphate both increase serum potassium. Use Caution/Monitor.

• porfimer

  hydrochlorothiazide, porfimer. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Enhanced photosensitivity.

• potassium acid phosphate

  potassium acid phosphate increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

• potassium chloride

  irbesartan and potassium chloride both increase serum potassium. Use Caution/Monitor.
  
  potassium chloride increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

• potassium citrate

  irbesartan and potassium citrate both increase serum potassium. Use Caution/Monitor.
  
  potassium citrate increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

• potassium citrate/citric acid

  irbesartan and potassium citrate/citric acid both increase serum potassium. Modify Therapy/Monitor Closely.

• probenecid

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

• potassium iodide

  potassium iodide and irbesartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.

• procainamide

  hydrochlorothiazide will increase the level or effect of procainamide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• propranolol

  propranolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and propranolol both increase serum potassium. Use Caution/Monitor.
  
  propranolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• quinidine

  quinidine will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• sacubitril/valsartan

  irbesartan and sacubitril/valsartan both increase serum potassium. Use Caution/Monitor.

• sacubitril/valsartan

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

• salicylates (non-asa)

  salicylates (non-asa) increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and salicylates (non-asa) both increase serum potassium. Use Caution/Monitor.

• salmeterol

  salmeterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• salsalate

  irbesartan and salsalate both increase serum potassium. Use Caution/Monitor.
  
  salsalate 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, salsalate. 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.

• salsalate

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

• selexipag

  irbesartan will increase the level or effect of selexipag by decreasing metabolism. Modify Therapy/Monitor Closely. Reduce selexipag dose to once daily if coadministered with moderate CYP2C8 inhibitors.

• shark cartilage

  hydrochlorothiazide, shark cartilage. Other (see comment). Use Caution/Monitor. Comment: May lead to hypercalcemia (theoretical).

• sodium sulfate/?magnesium sulfate/potassium chloride

  sodium sulfate/?magnesium sulfate/potassium chloride increases toxicity of hydrochlorothiazide 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/?magnesium sulfate/potassium chloride increases toxicity of irbesartan 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 chloride/magnesium sulfate/polyethylene glycol

  hydrochlorothiazide and sodium sulfate/potassium chloride/magnesium sulfate/polyethylene glycol both decrease serum potassium. Modify Therapy/Monitor Closely.

• sodium sulfate/potassium sulfate/magnesium sulfate

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

• sotalol

  irbesartan and sotalol both increase serum potassium. Use Caution/Monitor.
  
  sotalol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  sotalol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• spironolactone

  spironolactone increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.
  
  irbesartan and spironolactone both increase serum potassium. Modify Therapy/Monitor Closely.

• succinylcholine

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

• sulfasalazine

  irbesartan and sulfasalazine both increase serum potassium. Use Caution/Monitor.
  
  sulfasalazine 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, sulfasalazine. 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.

• sulfasalazine

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

• sulindac

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

• synthetic human angiotensin II

  irbesartan decreases effects of synthetic human angiotensin II by pharmacodynamic antagonism. Use Caution/Monitor.

• tadalafil

  tadalafil increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• tadalafil

  tadalafil increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• tazemetostat

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

• telmisartan

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

• temocillin

  temocillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• terbutaline

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

• terbutaline

  terbutaline and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• ticarcillin

  ticarcillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• timolol

  timolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  timolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and timolol both increase serum potassium. Use Caution/Monitor.

• tinidazole

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

• tolfenamic acid

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

• tizanidine

  tizanidine increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• tolfenamic acid

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

• tolmetin

  tolmetin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  tolmetin decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and tolmetin both increase serum potassium. Use Caution/Monitor.
  
  irbesartan, tolmetin. 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.

• tolvaptan

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

• toremifene

  hydrochlorothiazide, toremifene. Other (see comment). Use Caution/Monitor. Comment: Thiazide diuretics decrease renal calcium excretion and may increase risk of hypercalcemia in patients taking toremifene.

• torsemide

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

• torsemide

  torsemide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• treprostinil

  treprostinil increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor.

• triamterene

  triamterene increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.
  
  irbesartan and triamterene both increase serum potassium. Modify Therapy/Monitor Closely.

• trientine

  hydrochlorothiazide decreases levels of trientine by increasing renal clearance. Use Caution/Monitor.

• trimethoprim

  trimethoprim and irbesartan both increase serum potassium. Use Caution/Monitor. Trimethoprim decreases urinary potassium excretion. May cause hyperkalemia, particularly with high doses, renal insufficiency, or when combined with other drugs that cause hyperkalemia.

• umeclidinium bromide/vilanterol inhaled

  umeclidinium bromide/vilanterol inhaled and hydrochlorothiazide both decrease serum potassium. Modify Therapy/Monitor Closely. Electrocardiographic changes and/or hypokalemia associated with non?potassium-sparing diuretics may worsen with concomitant beta-agonists, particularly if recommended dose is exceeded

• valsartan

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

• vilanterol/fluticasone furoate inhaled

  vilanterol/fluticasone furoate inhaled and hydrochlorothiazide both decrease serum potassium. Modify Therapy/Monitor Closely. Beta-agonists may acutely worsen ECG changes and/or hypokalemia resulting from non-potassium-sparing diuretics

• vitamin D

  hydrochlorothiazide increases effects of vitamin D by Other (see comment). Use Caution/Monitor. Comment: Combination may increase hypercalcemic effect of vitamin D analogs. Use with caution.

• voclosporin

  voclosporin and irbesartan both increase serum potassium. Use Caution/Monitor.
  
  voclosporin, irbesartan. 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.

• xipamide

  xipamide increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor.
  
  xipamide increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor.

Minor (156)

• acarbose

  hydrochlorothiazide decreases effects of acarbose by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• aceclofenac

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

• acemetacin

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

• acyclovir

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

• agrimony

  agrimony increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.
  
  agrimony increases effects of irbesartan by pharmacodynamic synergism. Minor/Significance Unknown.

• albuterol

  albuterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• cornsilk

  cornsilk increases effects of irbesartan by pharmacodynamic synergism. Minor/Significance Unknown.

• aminohippurate sodium

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

• ampicillin

  hydrochlorothiazide increases levels of ampicillin by decreasing renal clearance. Minor/Significance Unknown.

• arformoterol

  arformoterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• aspirin

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

• aspirin rectal

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

• aspirin/citric acid/sodium bicarbonate

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

• balsalazide

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

• bendroflumethiazide

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

• birch

  birch increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• bitter melon

  bitter melon, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• brimonidine

  brimonidine increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• budesonide

  budesonide, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• calcitriol topical

  calcitriol topical, hydrochlorothiazide. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Potential additive hypercalcemia.

• calcium acetate

  hydrochlorothiazide increases levels of calcium acetate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• calcium carbonate

  hydrochlorothiazide increases levels of calcium carbonate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• calcium chloride

  hydrochlorothiazide increases levels of calcium chloride by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• calcium citrate

  hydrochlorothiazide increases levels of calcium citrate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• calcium gluconate

  hydrochlorothiazide increases levels of calcium gluconate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• carbenoxolone

  hydrochlorothiazide, carbenoxolone. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Additive hypokalemic effects.

• cefadroxil

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

• cefamandole

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

• cefpirome

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

• cefprozil

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

• ceftibuten

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

• celecoxib

  hydrochlorothiazide 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 hydrochlorothiazide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• chlorothiazide

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

• chlorpropamide

  hydrochlorothiazide will increase the level or effect of chlorpropamide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  hydrochlorothiazide decreases effects of chlorpropamide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• chlorthalidone

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

• colestipol

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

• cortisone

  cortisone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• cosyntropin

  cosyntropin, hydrochlorothiazide. pharmacodynamic synergism. Minor/Significance Unknown. Possible enhanced electrolyte loss.

• cyclopenthiazide

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

• deflazacort

  deflazacort, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• dexamethasone

  dexamethasone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• diazoxide

  diazoxide, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hyperglycemia.

• diclofenac

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

• diflunisal

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

• dobutamine

  dobutamine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• dopexamine

  dopexamine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• entecavir

  irbesartan, entecavir. Either increases effects of the other by decreasing renal clearance. Minor/Significance Unknown. Coadministration with drugs that reduce renal function or compete for active tubular secretion may increase serum concentrations of either entecavir or the coadministered drug.

• ephedrine

  ephedrine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• epinephrine

  epinephrine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• epinephrine racemic

  epinephrine racemic, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• epoprostenol

  epoprostenol increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Additive hypotensive effects.

• etodolac

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

• fenbufen

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

• fenoprofen

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

• fludrocortisone

  fludrocortisone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• flurbiprofen

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

• fo-ti

  fo-ti increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia (theoretical).

• folic acid

  hydrochlorothiazide decreases levels of folic acid by increasing renal clearance. Minor/Significance Unknown.

• formoterol

  formoterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• forskolin

  forskolin increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• ganciclovir

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

• glimepiride

  hydrochlorothiazide decreases effects of glimepiride by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• glipizide

  hydrochlorothiazide decreases effects of glipizide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• glyburide

  hydrochlorothiazide decreases effects of glyburide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• goldenrod

  goldenrod increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• hydrocortisone

  hydrocortisone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• ibuprofen

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

• indapamide

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

• indomethacin

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

• insulin aspart

  hydrochlorothiazide decreases effects of insulin aspart by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin detemir

  hydrochlorothiazide decreases effects of insulin detemir by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin glargine

  hydrochlorothiazide decreases effects of insulin glargine by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin glulisine

  hydrochlorothiazide decreases effects of insulin glulisine by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin lispro

  hydrochlorothiazide decreases effects of insulin lispro by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin NPH

  hydrochlorothiazide decreases effects of insulin NPH by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin regular human

  hydrochlorothiazide decreases effects of insulin regular human by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• isoproterenol

  isoproterenol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• ketoprofen

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

• ketorolac

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

• ketorolac intranasal

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

• L-methylfolate

  hydrochlorothiazide decreases levels of L-methylfolate by increasing renal clearance. Minor/Significance Unknown.

• levalbuterol

  levalbuterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• lornoxicam

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

• magnesium chloride

  hydrochlorothiazide decreases levels of magnesium chloride by increasing renal clearance. Minor/Significance Unknown.

• magnesium citrate

  hydrochlorothiazide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.

• magnesium hydroxide

  hydrochlorothiazide decreases levels of magnesium hydroxide by increasing renal clearance. Minor/Significance Unknown.

• magnesium oxide

  hydrochlorothiazide decreases levels of magnesium oxide by increasing renal clearance. Minor/Significance Unknown.

• magnesium sulfate

  hydrochlorothiazide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.

• meclofenamate

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

• mefenamic acid

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

• meloxicam

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

• memantine

  hydrochlorothiazide will increase the level or effect of memantine by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• mesalamine

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

• metaproterenol

  metaproterenol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• metformin

  hydrochlorothiazide will increase the level or effect of metformin by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  hydrochlorothiazide decreases effects of metformin by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• methotrexate

  hydrochlorothiazide increases toxicity of methotrexate by decreasing elimination. Minor/Significance Unknown. Increased myelosuppression.

• methylprednisolone

  methylprednisolone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• metolazone

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

• midodrine

  hydrochlorothiazide will increase the level or effect of midodrine by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• miglitol

  hydrochlorothiazide decreases effects of miglitol by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• minoxidil

  hydrochlorothiazide increases effects of minoxidil by pharmacodynamic synergism. Minor/Significance Unknown.

• nabumetone

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

• naproxen

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

• nateglinide

  hydrochlorothiazide decreases effects of nateglinide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• nirmatrelvir/ritonavir

  nirmatrelvir/ritonavir will decrease the level or effect of irbesartan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown. Irbesartan metabolized by glucuronidation and oxidation (mainly CYP2C9). Ritonavir is a weak CYP2C9 inducer and could potentially decrease irbesartan exposure. No dosage modification needed since induction reaches maximal effect after several days and the short duration of nirmatrelvir/ritonavir treatment.

• noni juice

  irbesartan and noni juice both increase serum potassium. Minor/Significance Unknown.
  
  noni juice increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Minor/Significance Unknown.

• norepinephrine

  norepinephrine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.
  
  hydrochlorothiazide decreases effects of norepinephrine by pharmacodynamic antagonism. Minor/Significance Unknown. May decrease responsiveness to norepinephrine but not enough to preclude effectiveness of the pressor agent therapeutic use.

• octacosanol

  octacosanol increases effects of irbesartan by pharmacodynamic synergism. Minor/Significance Unknown.

• octacosanol

  octacosanol increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• ofloxacin

  hydrochlorothiazide will increase the level or effect of ofloxacin by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• oxaprozin

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

• parecoxib

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

• patiromer

  patiromer, irbesartan. cation binding in GI tract. Minor/Significance Unknown. No observed clinically important interaction. No separation of dosing required.

• penicillin G aqueous

  hydrochlorothiazide increases levels of penicillin G aqueous by decreasing renal clearance. Minor/Significance Unknown.

• penicillin VK

  hydrochlorothiazide increases levels of penicillin VK by decreasing renal clearance. Minor/Significance Unknown.

• pioglitazone

  hydrochlorothiazide decreases effects of pioglitazone by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• piperacillin

  hydrochlorothiazide increases levels of piperacillin by decreasing renal clearance. Minor/Significance Unknown.

• pirbuterol

  pirbuterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• piroxicam

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

• prednisolone

  prednisolone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• prednisone

  prednisone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• quinine

  hydrochlorothiazide will increase the level or effect of quinine by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• reishi

  reishi increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.
  
  reishi increases effects of irbesartan by pharmacodynamic synergism. Minor/Significance Unknown.

• repaglinide

  hydrochlorothiazide decreases effects of repaglinide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• ruxolitinib

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

• rose hips

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

• rosiglitazone

  hydrochlorothiazide decreases effects of rosiglitazone by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• ruxolitinib topical

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

• salicylates (non-asa)

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

• salmeterol

  salmeterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• salsalate

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

• saxagliptin

  hydrochlorothiazide decreases effects of saxagliptin by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• shepherd's purse

  shepherd's purse, hydrochlorothiazide. Other (see comment). Minor/Significance Unknown. Comment: Theoretically, shepherd's purse may interfere with BP control.
  
  shepherd's purse, irbesartan. Other (see comment). Minor/Significance Unknown. Comment: Theoretically, shepherd's purse may interfere with BP control.

• sitagliptin

  hydrochlorothiazide decreases effects of sitagliptin by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• sulfadiazine

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

• sulfamethoxazole

  sulfamethoxazole will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  hydrochlorothiazide increases levels of sulfamethoxazole by unspecified interaction mechanism. Minor/Significance Unknown.
  
  hydrochlorothiazide, sulfamethoxazole. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Risk of hyponatremia.

• sulfasalazine

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

• sulfisoxazole

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

• sulindac

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

• terbutaline

  terbutaline, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.
  
  hydrochlorothiazide, terbutaline. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Additive hypokalemic effects.

• tizanidine

  tizanidine increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.

• tolazamide

  hydrochlorothiazide decreases effects of tolazamide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• tolbutamide

  hydrochlorothiazide decreases effects of tolbutamide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• tolfenamic acid

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

• tolmetin

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

• treprostinil

  treprostinil increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• triamcinolone acetonide injectable suspension

  triamcinolone acetonide injectable suspension, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• triamterene

  hydrochlorothiazide will increase the level or effect of triamterene by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• trilostane

  trilostane, hydrochlorothiazide. Other (see comment). Minor/Significance Unknown. Comment: Trilostane reduces K+ loss while maintaining the natriuretic effect. Mechanism: inhibition of mineralocorticoid steroid synthesis.

• trimethoprim

  hydrochlorothiazide will increase the level or effect of trimethoprim by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  hydrochlorothiazide, trimethoprim. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Risk of hyponatremia.

• valganciclovir

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

• verapamil

  hydrochlorothiazide will increase the level or effect of verapamil by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• verteporfin

  hydrochlorothiazide, verteporfin. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased phototoxicity.

• vildagliptin

  hydrochlorothiazide decreases effects of vildagliptin by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• willow bark

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

• acarbose

  Minor (1)hydrochlorothiazide decreases effects of acarbose by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• acebutolol

  Monitor Closely (3)irbesartan and acebutolol both increase serum potassium. Use Caution/Monitor.
  
  acebutolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  acebutolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• aceclofenac

  Monitor Closely (2)aceclofenac increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and aceclofenac both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of aceclofenac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• acemetacin

  Monitor Closely (2)irbesartan and acemetacin both increase serum potassium. Use Caution/Monitor.
  
  acemetacin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of acemetacin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• acyclovir

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

• agrimony

  Minor (2)agrimony increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.
  
  agrimony increases effects of irbesartan by pharmacodynamic synergism. Minor/Significance Unknown.

• albiglutide

  Monitor Closely (2)irbesartan increases effects of albiglutide by Other (see comment). Use Caution/Monitor. Comment: Angiotensin II receptor antagonists may enhance hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Monitor patients for changes in glycemic control.
  
  hydrochlorothiazide decreases effects of albiglutide by pharmacodynamic antagonism. Use Caution/Monitor. Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Monitor glycemic control especially when initiating, discontinuing, or increasing thiazide diuretic dose.

• albuterol

  Monitor Closely (2)irbesartan increases and albuterol decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  albuterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)albuterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• aldesleukin

  Monitor Closely (2)aldesleukin increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
  
  aldesleukin increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• aliskiren

  Contraindicated (1)irbesartan decreases effects of aliskiren by Other (see comment). Contraindicated. Comment: Aliskiren use contraindicated with ARBs in patients with diabetes; avoid coadministration with ARBs if GFR. In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, coadministration of ARBS 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.Monitor Closely (1)irbesartan decreases levels of aliskiren by unspecified interaction mechanism. Use Caution/Monitor.

• amifostine

  Monitor Closely (2)amifostine, irbesartan. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration with blood pressure lowering agents may increase the risk and severity of hypotension associated with amifostine. When amifostine is used at chemotherapeutic doses, withhold blood pressure lowering medications for 24 hr prior to amifostine; if blood pressure lowering medication cannot be withheld, do not administer amifostine.
  
  amifostine, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration with blood pressure lowering agents may increase the risk and severity of hypotension associated with amifostine. When amifostine is used at chemotherapeutic doses, withhold blood pressure lowering medications for 24 hr prior to amifostine; if blood pressure lowering medication cannot be withheld, do not administer amifostine.

• amiloride

  Monitor Closely (2)irbesartan and amiloride both increase serum potassium. Modify Therapy/Monitor Closely.
  
  amiloride increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

• aminohippurate sodium

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

• aminolevulinic acid oral

  Serious - Use Alternative (1)aminolevulinic acid oral, hydrochlorothiazide. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid administering other phototoxic drugs with aminolevulinic acid oral for 24 hr during perioperative period.

• aminolevulinic acid topical

  Serious - Use Alternative (1)hydrochlorothiazide increases toxicity of aminolevulinic acid topical by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration of photosensitizing drugs may enhance the phototoxic reaction to photodynamic therapy with aminolevulinic acid.

• amiodarone

  Monitor Closely (1)amiodarone will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• amoxicillin

  Monitor Closely (1)amoxicillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• ampicillin

  Minor (1)hydrochlorothiazide increases levels of ampicillin by decreasing renal clearance. Minor/Significance Unknown.

• arformoterol

  Monitor Closely (1)arformoterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)arformoterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• aspirin

  Monitor Closely (4)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.
  
  aspirin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  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.Minor (1)hydrochlorothiazide will increase the level or effect of aspirin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• aspirin rectal

  Monitor Closely (2)aspirin rectal increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor. .
  
  irbesartan and aspirin rectal both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of aspirin rectal by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• aspirin/citric acid/sodium bicarbonate

  Monitor Closely (4)irbesartan, aspirin/citric acid/sodium bicarbonate. 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.
  
  irbesartan and aspirin/citric acid/sodium bicarbonate both increase serum potassium. Use Caution/Monitor.
  
  aspirin/citric acid/sodium bicarbonate 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.
  
  aspirin/citric acid/sodium bicarbonate increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of aspirin/citric acid/sodium bicarbonate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• atenolol

  Monitor Closely (3)atenolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and atenolol both increase serum potassium. Use Caution/Monitor.
  
  atenolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• atogepant

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

• avanafil

  Monitor Closely (2)avanafil increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
  
  avanafil increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• axitinib

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

• balsalazide

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

• baricitinib

  Serious - Use Alternative (1)irbesartan will increase the level or effect of baricitinib by decreasing elimination. Avoid or Use Alternate Drug. Coadministration of baricitinib with strong organic anion transporter 3 (OAT3) inhibitors is not recommended.

• beclomethasone, inhaled

  Monitor Closely (1)beclomethasone, inhaled increases toxicity of hydrochlorothiazide by increasing elimination. Use Caution/Monitor. May increase the hypokalemic effects of thiazide diuretics.

• benazepril

  Monitor Closely (1)benazepril increases toxicity of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Enhanced hypotensive effects; increased risk of nephrotoxicity.Serious - Use Alternative (1)irbesartan, benazepril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• bendroflumethiazide

  Monitor Closely (2)bendroflumethiazide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.
  
  irbesartan increases and bendroflumethiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)bendroflumethiazide will increase the level or effect of hydrochlorothiazide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• betaxolol

  Monitor Closely (3)irbesartan and betaxolol both increase serum potassium. Use Caution/Monitor.
  
  betaxolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  betaxolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• birch

  Minor (1)birch increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• bisoprolol

  Monitor Closely (3)bisoprolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  bisoprolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and bisoprolol both increase serum potassium. Use Caution/Monitor.

• bitter melon

  Minor (1)bitter melon, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• bretylium

  Monitor Closely (2)hydrochlorothiazide, bretylium. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Each drug may cause hypotension.
  
  irbesartan, bretylium. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Each drug may cause hypotension.

• brimonidine

  Monitor Closely (1)brimonidine increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor.Minor (1)brimonidine increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• budesonide

  Minor (1)budesonide, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• bumetanide

  Monitor Closely (2)irbesartan increases and bumetanide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  bumetanide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• buprenorphine, long-acting injection

  Monitor Closely (1)buprenorphine, long-acting injection decreases effects of hydrochlorothiazide by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Opioids can reduce diuretic efficacy by inducing antidiuretic hormone release.

• calcifediol

  Monitor Closely (1)hydrochlorothiazide increases toxicity of calcifediol by Other (see comment). Use Caution/Monitor. Comment: Thiazide diuretics may increase serum calcium by decreasing urinary calcium excretion.

• calcitriol topical

  Minor (1)calcitriol topical, hydrochlorothiazide. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Potential additive hypercalcemia.

• calcium acetate

  Minor (1)hydrochlorothiazide increases levels of calcium acetate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• calcium carbonate

  Minor (1)hydrochlorothiazide increases levels of calcium carbonate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• calcium chloride

  Minor (1)hydrochlorothiazide increases levels of calcium chloride by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• calcium citrate

  Minor (1)hydrochlorothiazide increases levels of calcium citrate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• calcium gluconate

  Minor (1)hydrochlorothiazide increases levels of calcium gluconate by decreasing renal clearance. Minor/Significance Unknown. Risk of alkalosis, hypercalcemia.

• canagliflozin

  Monitor Closely (1)irbesartan and canagliflozin both increase serum potassium. Use Caution/Monitor.

• candesartan

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

• captopril

  Monitor Closely (1)captopril, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs lower blood pressure. Increased risk of nephrotoxicity. Monitor blood pressure and renal function.Serious - Use Alternative (1)irbesartan, captopril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• carbamazepine

  Serious - Use Alternative (1)carbamazepine, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased risk of systemic hyponatremia.

• carbenoxolone

  Monitor Closely (2)irbesartan increases and carbenoxolone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  hydrochlorothiazide and carbenoxolone both decrease serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide, carbenoxolone. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Additive hypokalemic effects.

• carbidopa

  Monitor Closely (2)carbidopa increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.
  
  carbidopa increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Therapy with carbidopa, given with or without levodopa or carbidopa-levodopa combination products, is started, dosage adjustment of the antihypertensive drug may be required.

• carvedilol

  Monitor Closely (3)carvedilol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and carvedilol both increase serum potassium. Use Caution/Monitor.
  
  carvedilol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• cefadroxil

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

• cefamandole

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

• cefpirome

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

• cefprozil

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

• ceftibuten

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

• celecoxib

  Monitor Closely (4)irbesartan and celecoxib both increase serum potassium. Use Caution/Monitor.
  
  celecoxib increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, celecoxib. 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.
  
  celecoxib 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.Minor (1)hydrochlorothiazide will increase the level or effect of celecoxib by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• celiprolol

  Monitor Closely (4)celiprolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  celiprolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and celiprolol both increase serum potassium. Use Caution/Monitor.
  
  hydrochlorothiazide decreases levels of celiprolol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

• cephalexin

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

• chlorothiazide

  Monitor Closely (2)chlorothiazide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.
  
  irbesartan increases and chlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)chlorothiazide will increase the level or effect of hydrochlorothiazide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• chlorpropamide

  Minor (2)hydrochlorothiazide will increase the level or effect of chlorpropamide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  hydrochlorothiazide decreases effects of chlorpropamide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• chlorthalidone

  Monitor Closely (2)irbesartan increases and chlorthalidone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  chlorthalidone and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)chlorthalidone will increase the level or effect of hydrochlorothiazide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cholestyramine

  Monitor Closely (1)cholestyramine decreases levels of hydrochlorothiazide by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

• choline magnesium trisalicylate

  Monitor Closely (3)irbesartan, choline magnesium trisalicylate. 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.
  
  choline magnesium trisalicylate decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and choline magnesium trisalicylate both increase serum potassium. Use Caution/Monitor.

• citalopram

  Monitor Closely (1)hydrochlorothiazide, citalopram. pharmacodynamic synergism. Use Caution/Monitor. Possible additive hyponatremia.

• colestipol

  Minor (1)colestipol decreases levels of hydrochlorothiazide by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.

• cornsilk

  Monitor Closely (1)cornsilk increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of hypokalemia (theoretical interaction).Minor (1)cornsilk increases effects of irbesartan by pharmacodynamic synergism. Minor/Significance Unknown.

• corticotropin

  Monitor Closely (1)corticotropin increases toxicity of hydrochlorothiazide by increasing renal clearance. Use Caution/Monitor. May enhance hypokalemic effect of thiazide diuretics.

• cortisone

  Minor (1)cortisone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• cosyntropin

  Minor (1)cosyntropin, hydrochlorothiazide. pharmacodynamic synergism. Minor/Significance Unknown. Possible enhanced electrolyte loss.

• cyclopenthiazide

  Monitor Closely (2)irbesartan increases and cyclopenthiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  cyclopenthiazide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)cyclopenthiazide will increase the level or effect of hydrochlorothiazide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• cyclophosphamide

  Serious - Use Alternative (1)hydrochlorothiazide increases toxicity of cyclophosphamide by decreasing renal clearance. Avoid or Use Alternate Drug. Increased myelosuppressive effects.

• cyclosporine

  Monitor Closely (1)cyclosporine increases toxicity of hydrochlorothiazide by unspecified interaction mechanism. Use Caution/Monitor. Coadministration of hydrochlorothiazide with cyclosporine may increase the risk of hypermagnesemia, hyperuricemia, and possible nephrotoxicity.Serious - Use Alternative (1)cyclosporine, hydrochlorothiazide. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased risk of systemic hyponatremia.

• dalteparin

  Monitor Closely (1)dalteparin increases toxicity of irbesartan by Other (see comment). Use Caution/Monitor. Comment: Low molecular weight heparins may suppress adrenal aldosterone secretion, which can potentially cause hyperkalemia.

• daprodustat

  Monitor Closely (1)irbesartan will increase the level or effect of daprodustat by Other (see comment). Modify Therapy/Monitor Closely. Moderate CYP2C8 inhibitors increase daprodustat exposure. If coadministered with moderate CYP2C8 inhibitors, reduce daprodustat starting dose by half (except if starting dose is already 1 mg). Monitor hemoglobin and adjust daprodustat dose when initiating or stopping therapy with moderate CYP2C8 inhibitors during treatment

• deflazacort

  Monitor Closely (1)hydrochlorothiazide and deflazacort both decrease serum potassium. Use Caution/Monitor.Minor (1)deflazacort, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• dexamethasone

  Minor (1)dexamethasone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• diazoxide

  Monitor Closely (1)hydrochlorothiazide increases toxicity of diazoxide by unspecified interaction mechanism. Use Caution/Monitor. May enhance hyperglycemic effects of diazoxide.Minor (1)diazoxide, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hyperglycemia.

• dichlorphenamide

  Monitor Closely (1)dichlorphenamide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• diclofenac

  Monitor Closely (4)diclofenac increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, diclofenac. 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.
  
  irbesartan and diclofenac both increase serum potassium. Use Caution/Monitor.
  
  diclofenac 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.Minor (1)hydrochlorothiazide will increase the level or effect of diclofenac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• dicloxacillin

  Monitor Closely (1)dicloxacillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• diflunisal

  Monitor Closely (4)irbesartan, diflunisal. 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.
  
  diflunisal decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and diflunisal both increase serum potassium. Use Caution/Monitor.
  
  diflunisal increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of diflunisal by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• digoxin

  Monitor Closely (4)hydrochlorothiazide increases effects of digoxin by pharmacodynamic synergism. Use Caution/Monitor. Hypokalemia increases digoxin effects.
  
  irbesartan and digoxin both increase serum potassium. Use Caution/Monitor.
  
  digoxin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  digoxin will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• dobutamine

  Monitor Closely (1)dobutamine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)dobutamine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• dofetilide

  Monitor Closely (1)dofetilide will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.Serious - Use Alternative (1)hydrochlorothiazide increases levels of dofetilide by decreasing renal clearance. Contraindicated. Risk of prolonged QTc interval.

• dopexamine

  Monitor Closely (2)irbesartan increases and dopexamine decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  dopexamine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)dopexamine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• drospirenone

  Monitor Closely (2)drospirenone increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.
  
  irbesartan and drospirenone both increase serum potassium. Modify Therapy/Monitor Closely.

• empagliflozin

  Monitor Closely (1)empagliflozin, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration of empagliflozin with diuretics results in increased urine volume and frequency of voids, which might enhance the potential for volume depletion.

• enalapril

  Serious - Use Alternative (1)irbesartan, enalapril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• enoxaparin

  Monitor Closely (1)enoxaparin increases toxicity of irbesartan by Other (see comment). Use Caution/Monitor. Comment: Low molecular weight heparins may suppress adrenal aldosterone secretion, which can potentially cause hyperkalemia.

• entecavir

  Minor (1)irbesartan, entecavir. Either increases effects of the other by decreasing renal clearance. Minor/Significance Unknown. Coadministration with drugs that reduce renal function or compete for active tubular secretion may increase serum concentrations of either entecavir or the coadministered drug.

• ephedrine

  Monitor Closely (1)ephedrine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)ephedrine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• epinephrine

  Monitor Closely (1)epinephrine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)epinephrine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• epinephrine racemic

  Monitor Closely (1)epinephrine racemic and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)epinephrine racemic, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• eplerenone

  Monitor Closely (1)irbesartan, eplerenone. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of hyperkalemia.

• epoprostenol

  Minor (1)epoprostenol increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Additive hypotensive effects.

• eprosartan

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

• erdafitinib

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

• esmolol

  Monitor Closely (3)irbesartan and esmolol both increase serum potassium. Use Caution/Monitor.
  
  esmolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  esmolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• ethacrynic acid

  Monitor Closely (2)irbesartan increases and ethacrynic acid decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  ethacrynic acid and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• etodolac

  Monitor Closely (4)etodolac increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, etodolac. 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.
  
  etodolac decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and etodolac both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of etodolac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• exenatide injectable solution

  Monitor Closely (2)irbesartan increases effects of exenatide injectable solution by Other (see comment). Use Caution/Monitor. Comment: Angiotensin II receptor antagonists may enhance hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Monitor patients for changes in glycemic control.
  
  hydrochlorothiazide decreases effects of exenatide injectable solution by pharmacodynamic antagonism. Use Caution/Monitor. Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Monitor glycemic control especially when initiating, discontinuing, or increasing thiazide diuretic dose.

• exenatide injectable suspension

  Monitor Closely (2)irbesartan increases effects of exenatide injectable suspension by Other (see comment). Use Caution/Monitor. Comment: Angiotensin II receptor antagonists may enhance hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Monitor patients for changes in glycemic control.
  
  hydrochlorothiazide decreases effects of exenatide injectable suspension by pharmacodynamic antagonism. Use Caution/Monitor. Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Monitor glycemic control especially when initiating, discontinuing, or increasing thiazide diuretic dose.

• fenbufen

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

• fenoprofen

  Monitor Closely (4)irbesartan, fenoprofen. 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.
  
  irbesartan and fenoprofen both increase serum potassium. Use Caution/Monitor.
  
  fenoprofen increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  fenoprofen 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.Minor (1)hydrochlorothiazide will increase the level or effect of fenoprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• fentanyl

  Monitor Closely (1)fentanyl decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• fentanyl intranasal

  Monitor Closely (1)fentanyl intranasal decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• fentanyl transdermal

  Monitor Closely (1)fentanyl transdermal decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• fentanyl transmucosal

  Monitor Closely (1)fentanyl transmucosal decreases effects of hydrochlorothiazide by Other (see comment). Modify Therapy/Monitor Closely. Comment: Fentanyl can reduce the efficacy of diuretics by inducing antidiuretic hormone release. Fentanyl may also lead to acute urinary retention by causing bladder sphincter spasm (particularly in men with enlarged prostates).

• finerenone

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

• flibanserin

  Monitor Closely (1)irbesartan 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

  Minor (1)fludrocortisone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• flurbiprofen

  Monitor Closely (4)irbesartan, flurbiprofen. 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.
  
  flurbiprofen increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  flurbiprofen decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and flurbiprofen both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of flurbiprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• fo-ti

  Minor (1)fo-ti increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia (theoretical).

• folic acid

  Minor (1)hydrochlorothiazide decreases levels of folic acid by increasing renal clearance. Minor/Significance Unknown.

• formoterol

  Monitor Closely (1)formoterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)formoterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• forskolin

  Minor (1)forskolin increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• fosinopril

  Serious - Use Alternative (1)irbesartan, fosinopril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• furosemide

  Monitor Closely (2)irbesartan increases and furosemide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  furosemide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.

• ganciclovir

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

• gentamicin

  Monitor Closely (2)irbesartan increases and gentamicin decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  hydrochlorothiazide and gentamicin both decrease serum potassium. Use Caution/Monitor.

• glimepiride

  Minor (1)hydrochlorothiazide decreases effects of glimepiride by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• glipizide

  Minor (1)hydrochlorothiazide decreases effects of glipizide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• glyburide

  Minor (1)hydrochlorothiazide decreases effects of glyburide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• goldenrod

  Minor (1)goldenrod increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• heparin

  Monitor Closely (1)heparin increases toxicity of irbesartan by Other (see comment). Use Caution/Monitor. Comment: Low molecular weight heparins may suppress adrenal aldosterone secretion, which can potentially cause hyperkalemia.

• hydrochlorothiazide

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

• hydrocortisone

  Minor (1)hydrocortisone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• ibuprofen

  Monitor Closely (4)ibuprofen increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, ibuprofen. 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.
  
  ibuprofen decreases effects of irbesartan by pharmacodynamic antagonism. Use Caution/Monitor. Antihypertensive effect of angiotensin receptor blockers may be attenuated by NSAIDs; monitor renal function and blood pressure periodically.
  
  irbesartan and ibuprofen both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of ibuprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ibuprofen IV

  Monitor Closely (5)irbesartan, ibuprofen IV. 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.
  
  irbesartan and ibuprofen IV both increase serum potassium. Use Caution/Monitor.
  
  ibuprofen IV decreases effects of irbesartan by pharmacodynamic antagonism. Use Caution/Monitor. Antihypertensive effect of angiotensin receptor blockers may be attenuated by NSAIDs; monitor renal function and blood pressure periodically.
  
  hydrochlorothiazide will increase the level or effect of ibuprofen IV by acidic (anionic) drug competition for renal tubular clearance. Use Caution/Monitor.
  
  ibuprofen IV increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor. NSAIDs may decrease the therapeutic effects of thiazide-like diuretics; may also enhance nephrotoxic effects.

• indacaterol, inhaled

  Monitor Closely (2)hydrochlorothiazide, indacaterol, inhaled. serum potassium. Use Caution/Monitor. Combination may increase risk of hypokalemia.
  
  indacaterol, inhaled, hydrochlorothiazide. Other (see comment). Use Caution/Monitor. Comment: Caution is advised in the coadministration of indacaterol neohaler with non-potassium-sparing diuretics.

• indapamide

  Monitor Closely (2)irbesartan increases and indapamide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  hydrochlorothiazide and indapamide both decrease serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of indapamide by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• indomethacin

  Monitor Closely (4)irbesartan, indomethacin. 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.
  
  indomethacin decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and indomethacin both increase serum potassium. Use Caution/Monitor.
  
  indomethacin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of indomethacin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• insulin aspart

  Monitor Closely (1)irbesartan increases effects of insulin aspart by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.Minor (1)hydrochlorothiazide decreases effects of insulin aspart by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin aspart protamine/insulin aspart

  Monitor Closely (1)irbesartan increases effects of insulin aspart protamine/insulin aspart by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin degludec

  Monitor Closely (3)irbesartan increases effects of insulin degludec by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.
  
  hydrochlorothiazide decreases effects of insulin degludec by Other (see comment). Use Caution/Monitor. Comment: Diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, possibly by diuretic-induced hpokalemia.
  
  irbesartan, insulin degludec. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.

• insulin degludec/insulin aspart

  Monitor Closely (2)irbesartan, insulin degludec/insulin aspart. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.
  
  hydrochlorothiazide decreases effects of insulin degludec/insulin aspart by Other (see comment). Use Caution/Monitor. Comment: Diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, possibly by diuretic-induced hpokalemia.

• insulin detemir

  Monitor Closely (1)irbesartan increases effects of insulin detemir by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.Minor (1)hydrochlorothiazide decreases effects of insulin detemir by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin glargine

  Monitor Closely (1)irbesartan increases effects of insulin glargine by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.Minor (1)hydrochlorothiazide decreases effects of insulin glargine by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin glulisine

  Monitor Closely (1)irbesartan increases effects of insulin glulisine by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.Minor (1)hydrochlorothiazide decreases effects of insulin glulisine by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin inhaled

  Monitor Closely (3)irbesartan, insulin inhaled. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.
  
  hydrochlorothiazide decreases effects of insulin inhaled by Other (see comment). Use Caution/Monitor. Comment: Diuretics may cause hyperglycemia and glycosuria in patients with diabetes mellitus, possibly by diuretic-induced hpokalemia.
  
  irbesartan increases effects of insulin inhaled by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin isophane human/insulin regular human

  Monitor Closely (1)irbesartan increases effects of insulin isophane human/insulin regular human by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin lispro

  Monitor Closely (1)irbesartan increases effects of insulin lispro by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.Minor (1)hydrochlorothiazide decreases effects of insulin lispro by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• insulin lispro protamine/insulin lispro

  Monitor Closely (1)irbesartan increases effects of insulin lispro protamine/insulin lispro by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin NPH

  Monitor Closely (1)irbesartan increases effects of insulin NPH by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.

• insulin regular human

  Monitor Closely (1)irbesartan increases effects of insulin regular human by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and ARBs may require insulin dosage adjustment and increased glucose monitoring.Minor (1)hydrochlorothiazide decreases effects of insulin regular human by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• irbesartan

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

• isavuconazonium sulfate

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

• isocarboxazid

  Serious - Use Alternative (1)isocarboxazid, hydrochlorothiazide. Other (see comment). Contraindicated. Comment: Additive hypotensive effects may be seen when MAOI's are combined with antihypertensives.

• isoproterenol

  Monitor Closely (1)isoproterenol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)isoproterenol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• ivacaftor

  Monitor Closely (1)irbesartan increases levels of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor when coadministered with weak CYP3A4 inhibitors .

• juniper

  Monitor Closely (1)juniper, hydrochlorothiazide. Other (see comment). Use Caution/Monitor. Comment: Juniper may potentiate or interfere with diuretic therapy. Juniper has diuretic effects, but may cause kidney damage at large doses.

• ketoprofen

  Monitor Closely (4)ketoprofen increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  ketoprofen 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, ketoprofen. 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.
  
  irbesartan and ketoprofen both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of ketoprofen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ketorolac

  Monitor Closely (4)irbesartan and ketorolac both increase serum potassium. Use Caution/Monitor.
  
  ketorolac 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, ketorolac. 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.
  
  ketorolac increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of ketorolac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ketorolac intranasal

  Monitor Closely (4)ketorolac intranasal decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and ketorolac intranasal both increase serum potassium. Use Caution/Monitor.
  
  ketorolac intranasal increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor. .
  
  irbesartan, ketorolac intranasal. 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.Minor (1)hydrochlorothiazide will increase the level or effect of ketorolac intranasal by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• L-methylfolate

  Minor (1)hydrochlorothiazide decreases levels of L-methylfolate by increasing renal clearance. Minor/Significance Unknown.

• labetalol

  Monitor Closely (3)irbesartan and labetalol both increase serum potassium. Use Caution/Monitor.
  
  labetalol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  labetalol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• lemborexant

  Monitor Closely (1)irbesartan 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.

• levalbuterol

  Monitor Closely (1)levalbuterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)levalbuterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• levodopa

  Monitor Closely (2)levodopa increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.
  
  levodopa increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Consider decreasing dosage of antihypertensive agent.

• lily of the valley

  Monitor Closely (1)hydrochlorothiazide increases toxicity of lily of the valley by Other (see comment). Use Caution/Monitor. Comment: Increased risk of cardiac toxicity due to K+ depletion.

• liraglutide

  Monitor Closely (2)hydrochlorothiazide decreases effects of liraglutide by pharmacodynamic antagonism. Use Caution/Monitor. Thiazide diuretics can decrease insulin sensitivity thereby leading to glucose intolerance and hyperglycemia. Monitor glycemic control especially when initiating, discontinuing, or increasing thiazide diuretic dose.
  
  irbesartan increases effects of liraglutide by Other (see comment). Use Caution/Monitor. Comment: Angiotensin II receptor antagonists may enhance hypoglycemic effects of antidiabetic agents by improving insulin sensitivity. Monitor patients for changes in glycemic control.

• lisinopril

  Serious - Use Alternative (1)irbesartan, lisinopril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• lithium

  Monitor Closely (1)hydrochlorothiazide increases toxicity of lithium by decreasing elimination. Use Caution/Monitor.Serious - Use Alternative (1)irbesartan increases toxicity of lithium by decreasing renal clearance. Avoid or Use Alternate Drug.

• lofexidine

  Serious - Use Alternative (2)lofexidine, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration with other drugs that decrease pulse or blood pressure to mitigate risk of excessive bradycardia and hypotension.
  
  lofexidine, irbesartan. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration with other drugs that decrease pulse or blood pressure to mitigate risk of excessive bradycardia and hypotension.

• lomitapide

  Monitor Closely (1)irbesartan increases levels of lomitapide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lomitapide dose should not exceed 30 mg/day.

• lonafarnib

  Serious - Use Alternative (1)irbesartan 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.

• lornoxicam

  Monitor Closely (2)irbesartan and lornoxicam both increase serum potassium. Use Caution/Monitor.
  
  lornoxicam increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of lornoxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• losartan

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

• lurasidone

  Monitor Closely (1)lurasidone increases effects of hydrochlorothiazide by Other (see comment). Use Caution/Monitor. Comment: Potential for increased risk of hypotension with concurrent use. Monitor blood pressure and adjust dose of antihypertensive agent as needed.

• magnesium chloride

  Minor (1)hydrochlorothiazide decreases levels of magnesium chloride by increasing renal clearance. Minor/Significance Unknown.

• magnesium citrate

  Minor (1)hydrochlorothiazide decreases levels of magnesium citrate by increasing renal clearance. Minor/Significance Unknown.

• magnesium hydroxide

  Minor (1)hydrochlorothiazide decreases levels of magnesium hydroxide by increasing renal clearance. Minor/Significance Unknown.

• magnesium oxide

  Minor (1)hydrochlorothiazide decreases levels of magnesium oxide by increasing renal clearance. Minor/Significance Unknown.

• magnesium sulfate

  Minor (1)hydrochlorothiazide decreases levels of magnesium sulfate by increasing renal clearance. Minor/Significance Unknown.

• maitake

  Monitor Closely (2)maitake increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor.
  
  maitake increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of hypokalemia (theoretical interaction).

• maraviroc

  Monitor Closely (1)maraviroc, irbesartan. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.

• meclofenamate

  Monitor Closely (4)irbesartan, meclofenamate. 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.
  
  irbesartan and meclofenamate both increase serum potassium. Use Caution/Monitor.
  
  meclofenamate increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  meclofenamate 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.Minor (1)hydrochlorothiazide will increase the level or effect of meclofenamate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• mefenamic acid

  Monitor Closely (4)mefenamic acid 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.
  
  mefenamic acid increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, mefenamic acid. 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.
  
  irbesartan and mefenamic acid both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of mefenamic acid by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• meloxicam

  Monitor Closely (4)meloxicam 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, meloxicam. 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.
  
  irbesartan and meloxicam both increase serum potassium. Use Caution/Monitor.
  
  meloxicam increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of meloxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• memantine

  Minor (1)hydrochlorothiazide will increase the level or effect of memantine by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• mesalamine

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

• metaproterenol

  Monitor Closely (1)metaproterenol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)metaproterenol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• metformin

  Minor (2)hydrochlorothiazide will increase the level or effect of metformin by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  hydrochlorothiazide decreases effects of metformin by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• methotrexate

  Minor (1)hydrochlorothiazide increases toxicity of methotrexate by decreasing elimination. Minor/Significance Unknown. Increased myelosuppression.

• methoxsalen

  Monitor Closely (1)methoxsalen, hydrochlorothiazide. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive photosensitizing effects.

• methyclothiazide

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

• methyl aminolevulinate

  Serious - Use Alternative (1)hydrochlorothiazide, methyl aminolevulinate. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Each drug may increase the photosensitizing effect of the other.

• methylphenidate

  Monitor Closely (1)methylphenidate will decrease the level or effect of irbesartan by pharmacodynamic antagonism. Use Caution/Monitor. Methylphenidate may diminish antihypertensive effects. Monitor BP.

• methylphenidate transdermal

  Monitor Closely (2)methylphenidate transdermal decreases effects of hydrochlorothiazide by anti-hypertensive channel blocking. Use Caution/Monitor.
  
  methylphenidate transdermal decreases effects of irbesartan by anti-hypertensive channel blocking. Use Caution/Monitor.

• methylprednisolone

  Minor (1)methylprednisolone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• metolazone

  Monitor Closely (2)irbesartan increases and metolazone decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  hydrochlorothiazide and metolazone both decrease serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of metolazone by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• metoprolol

  Monitor Closely (4)hydrochlorothiazide, metoprolol. Either increases toxicity of the other by Other (see comment). Modify Therapy/Monitor Closely. Comment: May cause idiosyncratic reaction, resulting in acute transient myopia and acute angle-closure glaucoma, which can lead to permanent vision loss.
  
  irbesartan and metoprolol both increase serum potassium. Use Caution/Monitor.
  
  metoprolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  metoprolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• midazolam intranasal

  Monitor Closely (1)irbesartan 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

  Minor (1)hydrochlorothiazide will increase the level or effect of midodrine by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• miglitol

  Minor (1)hydrochlorothiazide decreases effects of miglitol by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• minoxidil

  Minor (1)hydrochlorothiazide increases effects of minoxidil by pharmacodynamic synergism. Minor/Significance Unknown.

• moexipril

  Serious - Use Alternative (1)irbesartan, moexipril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• mometasone inhaled

  Monitor Closely (1)mometasone inhaled increases toxicity of hydrochlorothiazide by Other (see comment). Use Caution/Monitor. Comment: Corticosteroids may increase hypokalemic effect of loop diuretics.

• mycophenolate

  Monitor Closely (1)hydrochlorothiazide will increase the level or effect of mycophenolate by acidic (anionic) drug competition for renal tubular clearance. Use Caution/Monitor.

• nabumetone

  Monitor Closely (4)nabumetone 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.
  
  nabumetone increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, nabumetone. 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.
  
  irbesartan and nabumetone both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of nabumetone by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• nadolol

  Monitor Closely (3)nadolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and nadolol both increase serum potassium. Use Caution/Monitor.
  
  nadolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• nafcillin

  Monitor Closely (1)nafcillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• naproxen

  Monitor Closely (4)irbesartan and naproxen both increase serum potassium. Use Caution/Monitor.
  
  irbesartan, naproxen. 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.
  
  naproxen 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.
  
  naproxen increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of naproxen by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• nateglinide

  Minor (1)hydrochlorothiazide decreases effects of nateglinide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• nebivolol

  Monitor Closely (3)nebivolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and nebivolol both increase serum potassium. Use Caution/Monitor.
  
  nebivolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• nirmatrelvir/ritonavir

  Minor (1)nirmatrelvir/ritonavir will decrease the level or effect of irbesartan by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown. Irbesartan metabolized by glucuronidation and oxidation (mainly CYP2C9). Ritonavir is a weak CYP2C9 inducer and could potentially decrease irbesartan exposure. No dosage modification needed since induction reaches maximal effect after several days and the short duration of nirmatrelvir/ritonavir treatment.

• nitroglycerin rectal

  Monitor Closely (2)nitroglycerin rectal, irbesartan. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Observe for possible additive hypotensive effects during concomitant use. .
  
  nitroglycerin rectal, hydrochlorothiazide. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Observe for possible additive hypotensive effects during concomitant use. .

• noni juice

  Minor (2)irbesartan and noni juice both increase serum potassium. Minor/Significance Unknown.
  
  noni juice increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Minor/Significance Unknown.

• norepinephrine

  Monitor Closely (1)norepinephrine and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (2)norepinephrine, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.
  
  hydrochlorothiazide decreases effects of norepinephrine by pharmacodynamic antagonism. Minor/Significance Unknown. May decrease responsiveness to norepinephrine but not enough to preclude effectiveness of the pressor agent therapeutic use.

• octacosanol

  Minor (2)octacosanol increases effects of irbesartan by pharmacodynamic synergism. Minor/Significance Unknown.
  
  octacosanol increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• ofloxacin

  Minor (1)hydrochlorothiazide will increase the level or effect of ofloxacin by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• oliceridine

  Monitor Closely (1)oliceridine decreases effects of hydrochlorothiazide by Other (see comment). Use Caution/Monitor. Comment: Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone. Monitor for signs of diminished diuresis and/or effects on blood pressure and increase dosage of the diuretic as needed. .

• olmesartan

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

• olodaterol inhaled

  Monitor Closely (1)hydrochlorothiazide and olodaterol inhaled both decrease serum potassium. Use Caution/Monitor.

• oxaprozin

  Monitor Closely (4)irbesartan and oxaprozin both increase serum potassium. Use Caution/Monitor.
  
  oxaprozin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, oxaprozin. 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.
  
  oxaprozin 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.Minor (1)hydrochlorothiazide will increase the level or effect of oxaprozin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• paclitaxel

  Monitor Closely (1)irbesartan will increase the level or effect of paclitaxel by Other (see comment). Use Caution/Monitor. Paclitaxel levels/toxicity may increase when coadministered with CYP2C8 inhibitors

• paclitaxel protein bound

  Monitor Closely (1)irbesartan will increase the level or effect of paclitaxel protein bound by Other (see comment). Use Caution/Monitor. Paclitaxel levels/toxicity may increase when coadministered with CYP2C8 inhibitors

• parecoxib

  Monitor Closely (2)irbesartan and parecoxib both increase serum potassium. Use Caution/Monitor.
  
  parecoxib increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of parecoxib by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• patiromer

  Minor (1)patiromer, irbesartan. cation binding in GI tract. Minor/Significance Unknown. No observed clinically important interaction. No separation of dosing required.

• penbutolol

  Monitor Closely (3)penbutolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and penbutolol both increase serum potassium. Use Caution/Monitor.
  
  penbutolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• penicillin G aqueous

  Monitor Closely (1)penicillin G aqueous, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.Minor (1)hydrochlorothiazide increases levels of penicillin G aqueous by decreasing renal clearance. Minor/Significance Unknown.

• penicillin VK

  Minor (1)hydrochlorothiazide increases levels of penicillin VK by decreasing renal clearance. Minor/Significance Unknown.

• perindopril

  Serious - Use Alternative (1)irbesartan, perindopril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• pindolol

  Monitor Closely (3)pindolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  pindolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and pindolol both increase serum potassium. Use Caution/Monitor.

• pioglitazone

  Minor (1)hydrochlorothiazide decreases effects of pioglitazone by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• piperacillin

  Minor (1)hydrochlorothiazide increases levels of piperacillin by decreasing renal clearance. Minor/Significance Unknown.

• pirbuterol

  Monitor Closely (1)pirbuterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)pirbuterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• piroxicam

  Monitor Closely (4)irbesartan, piroxicam. 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.
  
  piroxicam increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and piroxicam both increase serum potassium. Use Caution/Monitor.
  
  piroxicam 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.Minor (1)hydrochlorothiazide will increase the level or effect of piroxicam by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• pivmecillinam

  Monitor Closely (1)pivmecillinam, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• porfimer

  Monitor Closely (1)hydrochlorothiazide, porfimer. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Enhanced photosensitivity.

• potassium acid phosphate

  Monitor Closely (2)potassium acid phosphate increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.
  
  irbesartan and potassium acid phosphate both increase serum potassium. Use Caution/Monitor.

• potassium chloride

  Monitor Closely (2)irbesartan and potassium chloride both increase serum potassium. Use Caution/Monitor.
  
  potassium chloride increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

• potassium citrate

  Monitor Closely (2)irbesartan and potassium citrate both increase serum potassium. Use Caution/Monitor.
  
  potassium citrate increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

• potassium citrate/citric acid

  Monitor Closely (1)irbesartan and potassium citrate/citric acid both increase serum potassium. Modify Therapy/Monitor Closely.

• potassium iodide

  Monitor Closely (1)potassium iodide and irbesartan both increase serum potassium. Use Caution/Monitor. Potassium salts may increase the hyperkalemic effects of ARBs; the effect may be the result of aldosterone suppression in patients receiving ARBs.

• prednisolone

  Minor (1)prednisolone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• prednisone

  Minor (1)prednisone, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• probenecid

  Monitor Closely (1)hydrochlorothiazide will increase the level or effect of probenecid by acidic (anionic) drug competition for renal tubular clearance. Use Caution/Monitor.

• procainamide

  Monitor Closely (1)hydrochlorothiazide will increase the level or effect of procainamide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• propranolol

  Monitor Closely (3)propranolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and propranolol both increase serum potassium. Use Caution/Monitor.
  
  propranolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• quinapril

  Serious - Use Alternative (1)irbesartan, quinapril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• quinidine

  Monitor Closely (1)quinidine will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Use Caution/Monitor.

• quinine

  Minor (1)hydrochlorothiazide will increase the level or effect of quinine by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• ramipril

  Serious - Use Alternative (1)irbesartan, ramipril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• reishi

  Minor (2)reishi increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.
  
  reishi increases effects of irbesartan by pharmacodynamic synergism. Minor/Significance Unknown.

• repaglinide

  Minor (1)hydrochlorothiazide decreases effects of repaglinide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• rose hips

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

• rosiglitazone

  Minor (1)hydrochlorothiazide decreases effects of rosiglitazone by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• ruxolitinib

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

• ruxolitinib topical

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

• sacubitril/valsartan

  Monitor Closely (2)sacubitril/valsartan increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and sacubitril/valsartan both increase serum potassium. Use Caution/Monitor.

• salicylates (non-asa)

  Monitor Closely (2)irbesartan and salicylates (non-asa) both increase serum potassium. Use Caution/Monitor.
  
  salicylates (non-asa) increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of salicylates (non-asa) by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• salmeterol

  Monitor Closely (1)salmeterol and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (1)salmeterol, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• salsalate

  Monitor Closely (4)irbesartan, salsalate. 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.
  
  salsalate increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  salsalate decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and salsalate both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of salsalate by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• saxagliptin

  Minor (1)hydrochlorothiazide decreases effects of saxagliptin by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• selexipag

  Monitor Closely (1)irbesartan will increase the level or effect of selexipag by decreasing metabolism. Modify Therapy/Monitor Closely. Reduce selexipag dose to once daily if coadministered with moderate CYP2C8 inhibitors.

• shark cartilage

  Monitor Closely (1)hydrochlorothiazide, shark cartilage. Other (see comment). Use Caution/Monitor. Comment: May lead to hypercalcemia (theoretical).

• shepherd's purse

  Minor (2)shepherd's purse, irbesartan. Other (see comment). Minor/Significance Unknown. Comment: Theoretically, shepherd's purse may interfere with BP control.
  
  shepherd's purse, hydrochlorothiazide. Other (see comment). Minor/Significance Unknown. Comment: Theoretically, shepherd's purse may interfere with BP control.

• siponimod

  Serious - Use Alternative (1)irbesartan will increase the level or effect of siponimod by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with drugs that cause moderate CYP2C9 AND a moderate or strong CYP3A4 inhibition is not recommended. Caution if siponimod coadministered with moderate CYP2C9 inhibitors alone.

• sitagliptin

  Minor (1)hydrochlorothiazide decreases effects of sitagliptin by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• sodium sulfate/?magnesium sulfate/potassium chloride

  Monitor Closely (2)sodium sulfate/?magnesium sulfate/potassium chloride increases toxicity of hydrochlorothiazide 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/?magnesium sulfate/potassium chloride increases toxicity of irbesartan 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 chloride/magnesium sulfate/polyethylene glycol

  Monitor Closely (1)hydrochlorothiazide and sodium sulfate/potassium chloride/magnesium sulfate/polyethylene glycol both decrease serum potassium. Modify Therapy/Monitor Closely.

• sodium sulfate/potassium sulfate/magnesium sulfate

  Monitor Closely (2)sodium sulfate/potassium sulfate/magnesium sulfate increases toxicity of irbesartan 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 increases toxicity of hydrochlorothiazide by Other (see comment). Use Caution/Monitor. Comment: Coadministration with medications that cause fluid and electrolyte abnormalities may increase the risk of adverse events of seizure, arrhythmias, and renal impairment.

• sotalol

  Monitor Closely (3)irbesartan and sotalol both increase serum potassium. Use Caution/Monitor.
  
  sotalol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  sotalol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.

• sparsentan

  Contraindicated (1)sparsentan, irbesartan. Either increases toxicity of the other by pharmacodynamic synergism. Contraindicated. Coadministration of ARBs with sparsentan is associated with increased risks of hypotension, syncope, hyperkalemia, and changes in renal function (eg, acute renal failure).

• spironolactone

  Monitor Closely (2)spironolactone increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.
  
  irbesartan and spironolactone both increase serum potassium. Modify Therapy/Monitor Closely.

• squill

  Serious - Use Alternative (1)hydrochlorothiazide increases toxicity of squill by Other (see comment). Avoid or Use Alternate Drug. Comment: Potassium depletion may enhance toxicity of squill.

• succinylcholine

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

• sulfadiazine

  Minor (1)hydrochlorothiazide increases levels of sulfadiazine by unspecified interaction mechanism. Minor/Significance Unknown.

• sulfamethoxazole

  Minor (3)sulfamethoxazole will increase the level or effect of hydrochlorothiazide by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  hydrochlorothiazide increases levels of sulfamethoxazole by unspecified interaction mechanism. Minor/Significance Unknown.
  
  hydrochlorothiazide, sulfamethoxazole. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Risk of hyponatremia.

• sulfasalazine

  Monitor Closely (4)irbesartan, sulfasalazine. 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.
  
  irbesartan and sulfasalazine both increase serum potassium. Use Caution/Monitor.
  
  sulfasalazine 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.
  
  sulfasalazine increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of sulfasalazine by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• sulfisoxazole

  Minor (1)hydrochlorothiazide increases levels of sulfisoxazole by unspecified interaction mechanism. Minor/Significance Unknown.

• sulindac

  Monitor Closely (4)irbesartan and sulindac both increase serum potassium. Use Caution/Monitor.
  
  sulindac increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan, sulindac. 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.
  
  sulindac 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.Minor (1)hydrochlorothiazide will increase the level or effect of sulindac by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• synthetic human angiotensin II

  Monitor Closely (1)irbesartan decreases effects of synthetic human angiotensin II by pharmacodynamic antagonism. Use Caution/Monitor.

• tadalafil

  Monitor Closely (2)tadalafil increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.
  
  tadalafil increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

• tazemetostat

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

• telmisartan

  Monitor Closely (2)telmisartan increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and telmisartan both increase serum potassium. Use Caution/Monitor.

• temocillin

  Monitor Closely (1)temocillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• terbutaline

  Monitor Closely (2)irbesartan increases and terbutaline decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  terbutaline and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.Minor (2)hydrochlorothiazide, terbutaline. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Additive hypokalemic effects.
  
  terbutaline, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Hypokalemia.

• ticarcillin

  Monitor Closely (1)ticarcillin, hydrochlorothiazide. Either increases levels of the other by decreasing renal clearance. Use Caution/Monitor.

• timolol

  Monitor Closely (3)timolol, irbesartan. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Risk of fetal compromise if given during pregnancy.
  
  irbesartan and timolol both increase serum potassium. Use Caution/Monitor.
  
  timolol increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• tinidazole

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

• tizanidine

  Monitor Closely (1)tizanidine increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.Minor (1)tizanidine increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.

• tolazamide

  Minor (1)hydrochlorothiazide decreases effects of tolazamide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• tolbutamide

  Minor (1)hydrochlorothiazide decreases effects of tolbutamide by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• tolfenamic acid

  Monitor Closely (2)tolfenamic acid increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and tolfenamic acid both increase serum potassium. Use Caution/Monitor.Minor (1)hydrochlorothiazide will increase the level or effect of tolfenamic acid by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• tolmetin

  Monitor Closely (4)tolmetin increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  tolmetin decreases effects of irbesartan by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. NSAIDs decrease synthesis of vasodilating renal prostaglandins, and thus affect fluid homeostasis and may diminish antihypertensive effect.
  
  irbesartan and tolmetin both increase serum potassium. Use Caution/Monitor.
  
  irbesartan, tolmetin. 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.Minor (1)hydrochlorothiazide will increase the level or effect of tolmetin by acidic (anionic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• tolvaptan

  Monitor Closely (2)tolvaptan increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.
  
  irbesartan and tolvaptan both increase serum potassium. Use Caution/Monitor.

• toremifene

  Monitor Closely (1)hydrochlorothiazide, toremifene. Other (see comment). Use Caution/Monitor. Comment: Thiazide diuretics decrease renal calcium excretion and may increase risk of hypercalcemia in patients taking toremifene.

• torsemide

  Monitor Closely (2)torsemide and hydrochlorothiazide both decrease serum potassium. Use Caution/Monitor.
  
  irbesartan increases and torsemide decreases serum potassium. Effect of interaction is not clear, use caution. Use Caution/Monitor.

• trandolapril

  Serious - Use Alternative (1)irbesartan, trandolapril. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Dual blockade of renin-angiotensin system increases risks of hypotension, hyperkalemia, and renal impairment.

• treprostinil

  Monitor Closely (1)treprostinil increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor.Minor (1)treprostinil increases effects of hydrochlorothiazide by pharmacodynamic synergism. Minor/Significance Unknown.

• tretinoin

  Serious - Use Alternative (1)hydrochlorothiazide, tretinoin. Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased phototoxicity.

• tretinoin topical

  Serious - Use Alternative (1)hydrochlorothiazide, tretinoin topical. Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased phototoxicity.

• triamcinolone acetonide injectable suspension

  Minor (1)triamcinolone acetonide injectable suspension, hydrochlorothiazide. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypokalemia, especially with strong glucocorticoid activity.

• triamterene

  Monitor Closely (2)irbesartan and triamterene both increase serum potassium. Modify Therapy/Monitor Closely.
  
  triamterene increases and hydrochlorothiazide decreases serum potassium. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.Minor (1)hydrochlorothiazide will increase the level or effect of triamterene by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• trientine

  Monitor Closely (1)hydrochlorothiazide decreases levels of trientine by increasing renal clearance. Use Caution/Monitor.

• trilostane

  Minor (1)trilostane, hydrochlorothiazide. Other (see comment). Minor/Significance Unknown. Comment: Trilostane reduces K+ loss while maintaining the natriuretic effect. Mechanism: inhibition of mineralocorticoid steroid synthesis.

• trimethoprim

  Monitor Closely (1)trimethoprim and irbesartan both increase serum potassium. Use Caution/Monitor. Trimethoprim decreases urinary potassium excretion. May cause hyperkalemia, particularly with high doses, renal insufficiency, or when combined with other drugs that cause hyperkalemia.Minor (2)hydrochlorothiazide will increase the level or effect of trimethoprim by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.
  
  hydrochlorothiazide, trimethoprim. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Risk of hyponatremia.

• tucatinib

  Serious - Use Alternative (1)irbesartan will increase the level or effect of tucatinib by Other (see comment). Avoid or Use Alternate Drug. Coadministration of tucatinib (a CYP2C8 substrate) with a strong or moderate CYP2C8 inhibitors increases tucatinib plasma concentrations and risk of toxicities.

• umeclidinium bromide/vilanterol inhaled

  Monitor Closely (1)umeclidinium bromide/vilanterol inhaled and hydrochlorothiazide both decrease serum potassium. Modify Therapy/Monitor Closely. Electrocardiographic changes and/or hypokalemia associated with non?potassium-sparing diuretics may worsen with concomitant beta-agonists, particularly if recommended dose is exceeded

• valganciclovir

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

• valsartan

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

• verapamil

  Minor (1)hydrochlorothiazide will increase the level or effect of verapamil by basic (cationic) drug competition for renal tubular clearance. Minor/Significance Unknown.

• verteporfin

  Minor (1)hydrochlorothiazide, verteporfin. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Increased phototoxicity.

• vilanterol/fluticasone furoate inhaled

  Monitor Closely (1)vilanterol/fluticasone furoate inhaled and hydrochlorothiazide both decrease serum potassium. Modify Therapy/Monitor Closely. Beta-agonists may acutely worsen ECG changes and/or hypokalemia resulting from non-potassium-sparing diuretics

• vildagliptin

  Minor (1)hydrochlorothiazide decreases effects of vildagliptin by pharmacodynamic antagonism. Minor/Significance Unknown. Thiazide dosage >50 mg/day may increase blood glucose.

• vitamin D

  Monitor Closely (1)hydrochlorothiazide increases effects of vitamin D by Other (see comment). Use Caution/Monitor. Comment: Combination may increase hypercalcemic effect of vitamin D analogs. Use with caution.

• voclosporin

  Monitor Closely (2)voclosporin and irbesartan both increase serum potassium. Use Caution/Monitor.
  
  voclosporin, irbesartan. 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.

• willow bark

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

• xipamide

  Monitor Closely (2)xipamide increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor.
  
  xipamide increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor.

• zavegepant intranasal

  Serious - Use Alternative (1)irbesartan will increase the level or effect of zavegepant intranasal by Other (see comment). Avoid or Use Alternate Drug. NTCP inhibitors may result in a significant increase in systemic exposure of zavegepant (a NTCP substrate).