Pentoxifylline interactions

Pentoxifylline (Trental), a methylxanthine has 252 documented interactions across the FDA labels and fact sheets we index: 16 major, 199 moderate, 28 minor, and 9 where a label reports no significant interaction. Each entry below quotes the sentence behind it. This drug page is a starting point, not a verdict for your situation.

Interactions from the label

Major interactions (16)

  • AdenosineantiarrhythmicMajor

    Use of methylxanthines (e.g., caffeine, aminophylline and theophylline) is not recommended in patients who experience a seizures in association with adenosine injection ( 5.6 ) (Adenosine label, Warnings and precautions)

  • CONTRAINDICATIONS Pentoxifylline extended-release tablets should not be used in patients with recent cerebral and/or retinal hemorrhage or in patients who have previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine. (Pentoxifylline label, Contraindications)

  • CONTRAINDICATIONS Pentoxifylline extended-release tablets should not be used in patients with recent cerebral and/or retinal hemorrhage or in patients who have previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine. (Pentoxifylline label, Contraindications)

  • CONTRAINDICATIONS Pentoxifylline extended-release tablets should not be used in patients with recent cerebral and/or retinal hemorrhage or in patients who have previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine. (Pentoxifylline label, Contraindications)

  • CONTRAINDICATIONS Pentoxifylline extended-release tablets should not be used in patients with recent cerebral and/or retinal hemorrhage or in patients who have previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine. (Pentoxifylline label, Contraindications)

  • CaffeineFood and drinkMajor

    CONTRAINDICATIONS Pentoxifylline extended-release tablets should not be used in patients with recent cerebral and/or retinal hemorrhage or in patients who have previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine. (Pentoxifylline label, Contraindications)

  • CiprofloxacinfluoroquinoloneMajor

    Serious Adverse Reactions with Concomitant Theophylline Serious and fatal reactions have been reported in patients receiving concurrent administration of ciprofloxacin and theophylline. (Ciprofloxacin label, Warnings and precautions)

  • Deferasiroxiron supplementMajor

    Avoid the use of Exjade with CYP1A2 substrate theophylline. (Deferasirox label, Drug interactions)

  • EpinephrinesympathomimeticMajor

    …hormones Diuretics Cardiac glycosides, such as digitalis glycosides Quinidine Drugs potentiating hypokalemic effects of epinephrine • Potassium depleting diuretics • Corticosteroids • Theophylline Epinephrine should not be used to counteract circulatory collapse or hypotension caused by phenothiazines, as a reversal of the pressor effects of epinephrine may result… (Epinephrine label, Drug interactions)

  • Ergotamine and caffeineergot alkaloidMajor

    CONTRAINDICATIONS Pentoxifylline extended-release tablets should not be used in patients with recent cerebral and/or retinal hemorrhage or in patients who have previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine. (Pentoxifylline label, Contraindications)

  • KetamineCNS depressantMajor

    Theophylline or Aminophylline : Do not co-administer with KETALAR as concomitant use may lower the seizure threshold ( 7.1 ). (Ketamine label, Drug interactions)

  • KetorolacNSAIDMajor

    The concomitant use of ketorolac tromethamine and pentoxifylline is contraindicated. (Ketorolac label, Contraindications)

  • CONTRAINDICATIONS Pentoxifylline extended-release tablets should not be used in patients with recent cerebral and/or retinal hemorrhage or in patients who have previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine. (Pentoxifylline label, Contraindications)

  • RifampinantibioticMajor

    Quinine Prevention or Management : Avoid concomitant use Decrease AUC by 75%-85% Telithromycin Decrease AUC by 86% Theophylline Decrease exposure by 20%-40% Effect of Other Drugs on Rifampin Concomitant antacid administration may reduce the absorption of rifampin. (Rifampin label, Drug interactions)

  • RiociguatvasodilatorMajor

    Phosphodiesterase Inhibitors Concomitant administration of Adempas with specific PDE-5 inhibitors (such as sildenafil, tadalafil, or vardenafil) or nonspecific PDE-5 inhibitors (such as dipyridamole or theophylline) is contraindicated [see Dosage and Administration (2.6), Drug Interactions ( 7.1 ) and Clinical Pharmacology ( 12.2 )]. (Riociguat label, Contraindications)

  • TheophyllinemethylxanthineMajor

    CONTRAINDICATIONS Pentoxifylline extended-release tablets should not be used in patients with recent cerebral and/or retinal hemorrhage or in patients who have previously exhibited intolerance to this product or methylxanthines such as caffeine, theophylline, and theobromine. (Pentoxifylline label, Contraindications)

Moderate interactions (199)

  • Acebutololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • AclidiniumanticholinergicModerate

    Sympathomimetics, Methylxanthines, Steroids In clinical studies, concurrent administration of aclidinium bromide and other drugs commonly used in the treatment of COPD including sympathomimetics (short-acting beta 2 agonists), methylxanthines, and oral and inhaled steroids showed no increases in adverse drug reactions. (Aclidinium label, Drug interactions)

  • AdalimumabimmunosuppressantModerate

    Upon initiation or discontinuation of Adalimumab-fkjp in patients being treated with CYP450 substrates with a narrow therapeutic index, monitoring of the effect (e.g., warfarin) or drug concentration (e.g., cyclosporine or theophylline) is recommended and the individual dose of the drug product may be adjusted as needed. (Adalimumab label, Drug interactions)

  • AlbendazoleModerate

    Theophylline: Albendazole induces cytochrome P450 1A in human hepatoma cells; therefore, it is recommended that plasma concentrations of theophylline be monitored during and after treatment. (Albendazole label, Drug interactions)

  • AliskirenantihypertensiveModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Amiloridepotassium-sparing diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • AminophyllinemethylxanthineModerate

    Pentoxifylline Decreases theophylline clearance. (Aminophylline label, Drug interactions)

  • Amlodipinedihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Amlodipine and atorvastatindihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Amlodipine and benazeprildihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Amlodipine and olmesartandihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Amlodipine and valsartandihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • ApixabananticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Arformoterolbeta-adrenergic agonistModerate

    Xanthine derivatives, steroids, diuretics, or non-potassium sparing diuretics may potentiate hypokalemia or ECG changes. (Arformoterol label, Drug interactions)

  • ArgatrobananticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • AspirinNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Aspirin and dipyridamoleantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Atenololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Atenolol and chlorthalidonebeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • AzathioprineimmunosuppressantModerate

    It is recommended that a further dose reduction or alternative therapies be considered for patients with low or absent TPMT activity receiving IMURAN and xanthine oxidase inhibitors because both TPMT and XO inactivation pathways are affected (see CLINICAL PHARMACOLOGY, WARNINGS, PRECAUTIONS: Laboratory Tests and ADVERSE REACTIONS sections). (Azathioprine label, Drug interactions)

  • Azilsartanangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • BenazeprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Betaxololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Bisoprololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • BivalirudinanticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • BupropionantidepressantModerate

    …also increase the risk of seizure: concomitant use of other medications that lower the seizure threshold (e.g., other bupropion products, antipsychotics, tricyclic antidepressants, theophylline, and systemic corticosteroids), metabolic disorders (e.g., hypoglycemia, hyponatremia, severe hepatic impairment, and hypoxia), or use of illicit drugs (e.g., cocaine)… (Bupropion label, Warnings and precautions)

  • ButorphanolopioidModerate

    …Interactions It is not known if the effects of Butorphanol Tartrate Injection are altered by concomitant medications that affect hepatic metabolism of drugs (CYP 450 inhibitors or inducers) (e.g., erythromycin, theophylline, etc.), but physicians should be alert to the possibility that a smaller initial dose and longer intervals between doses may be needed. (Butorphanol label, Drug interactions)

  • Candesartanangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Candesartan and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Cangrelorantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Cannabidiol (prescription)anticonvulsantModerate

    Concomitant administration of strong CYP1A2 inhibitors (including e.g., ciprofloxacin or fluvoxamine) may increase the exposure to pentoxifylline (see ADVERSE REACTIONS). (Pentoxifylline label, Drug interactions)

  • CaptoprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Carvedilolbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • CelecoxibNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • CetirizineantihistamineModerate

    There was a small decrease in the clearance of oral cetirizine hydrochloride caused by a 400-mg dose of theophylline; it is possible that larger theophylline doses could have a greater effect [see Clinical Pharmacology ( 12.3 )]. (Cetirizine label, Drug interactions)

  • Chlorothiazidethiazide diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Chlorthalidonethiazide diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Cilostazolantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • CimetidineH2 blockerModerate

    Concomitant administration with cimetidine is reported to increase the average steady state plasma concentration of pentoxifylline (~25%) and the Metabolite I (~30%). (Pentoxifylline label, Drug interactions)

  • Clarithromycinmacrolide antibioticModerate

    Xanthine Derivatives: Theophylline Use With Caution Theophylline: Clarithromycin use in patients who are receiving theophylline may be associated with an increase of serum theophylline concentrations [see Pharmacokinetics ( 12.3 )] . (Clarithromycin label, Drug interactions)

  • Clonidinealpha-adrenergic agonistModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Clopidogrelantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • DabigatrananticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Desogestrel and ethinyl estradioloral contraceptiveModerate

    Effects of Combined Hormonal Contraceptives on Other Drugs COCs containing EE may inhibit the metabolism of other compounds (e.g., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole) and increase their plasma concentrations. (Desogestrel and ethinyl estradiol label, Drug interactions)

  • Dichlorphenamidecarbonic anhydrase inhibitorModerate

    Drugs that Cause Hypokalemia The risk of hypokalemia is greater with coadministration of KEVEYIS and other drugs that can cause hypokalemia (e.g., loop diuretics, thiazide diuretics, laxatives, antifungals, penicillins, and theophylline) [see Warnings and Precautions (5.3) ] . (Dichlorphenamide label, Drug interactions)

  • DiclofenacNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • DiflunisalNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Diltiazemcalcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Dipyridamoleantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • DoxapramModerate

    There may be an interaction between doxapram and aminophylline and between doxapram and theophylline manifested by increased skeletal muscle activity, agitation, and hyperactivity. (Doxapram label, Drug interactions)

  • Doxazosinalpha blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Drospirenone and ethinyl estradioloral contraceptiveModerate

    …studies, administration of a hormonal contraceptive containing EE did not lead to any increase or only to a weak increase in plasma concentrations of CYP3A4 substrates (e.g., midazolam) while plasma concentrations of CYP2C19 substrates (e.g., omeprazole and voriconazole) and CYP1A2 substrates (e.g., theophylline and tizanidine) can have a weak or moderate increase. (Drospirenone and ethinyl estradiol label, Drug interactions)

  • Dutasteride and tamsulosin5-alpha reductase inhibitorModerate

    Tamsulosin Dosage adjustments are not necessary when tamsulosin is administered concomitantly with digoxin or theophylline [see Clinical Pharmacology (12.3) ]. (Dutasteride and tamsulosin label, Drug interactions)

  • EdoxabananticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • EnalaprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • EnalaprilatACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • EnoxaparinanticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Eplerenonealdosterone antagonistModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Eptifibatideantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Erythromycinmacrolide antibioticModerate

    Drug Interactions Theophylline Erythromycin use in patients who are receiving high doses of theophylline may be associated with an increase in serum theophylline levels and potential theophylline toxicity. (Erythromycin label, Drug interactions)

  • Ethacrynic acidloop diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • EtodolacNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Effects of CHCs on Other Drugs CHCs containing ethinyl estradiol may inhibit the metabolism of other compounds (e.g., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole) and increase their plasma concentrations. (Etonogestrel and ethinyl estradiol label, Drug interactions)

  • Felodipinedihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • FenoprofenNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Fluconazoleazole antifungalModerate

    (See CLINICAL PHARMACOLOGY: Drug Interaction Studies .) Theophylline Fluconazole increases the serum concentrations of theophylline. (Fluconazole label, Drug interactions)

  • FlurbiprofenNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • FluvoxamineSSRIModerate

    Concomitant administration of strong CYP1A2 inhibitors (including e.g., ciprofloxacin or fluvoxamine) may increase the exposure to pentoxifylline (see ADVERSE REACTIONS). (Pentoxifylline label, Drug interactions)

  • FondaparinuxanticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Formoterolbeta-adrenergic agonistModerate

    • Xanthine derivatives, steroids, diuretics, or non-potassium sparing diuretics may potentiate hypokalemia or ECG changes. (Formoterol label, Drug interactions)

  • FosinoprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • FosphenytoinanticonvulsantModerate

    John's wort may vary widely based on preparation. theophylline Drugs that may either increase or decrease phenytoin serum levels Antiepileptic drugs Phenobarbital, valproate sodium, valproic acid 7.2 Drugs Affected by Phenytoin or CEREBYX Table 7 includes commonly occurring drug interactions affected by phenytoin (the active metabolite of CEREBYX). (Fosphenytoin label, Drug interactions)

  • Furosemideloop diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • GlimepiridesulfonylureaModerate

    …intensity of hypoglycemia: oral anti-diabetic medications, pramlintide acetate, insulin, angiotensin converting enzyme (ACE) inhibitors, H 2 receptor antagonists, fibrates, propoxyphene, pentoxifylline, somatostatin analogs, anabolic steroids and androgens, cyclophosphamide, phenyramidol, guanethidine, fluconazole, sulfinpyrazone, tetracyclines, clarithromycin, disopyramide,… (Glimepiride label, Drug interactions)

  • GlipizidesulfonylureaModerate

    …to and/or intensity of hypoglycemia: antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline, pramlintide, propoxyphene, salicylates, somatostatin analogs (e.g., octreotide), sulfonamide antibiotics, nonsteroidal anti-inflammatory agents, chloramphenicol, probenecid,… (Glipizide label, Drug interactions)

  • Guanfacinealpha-adrenergic agonistModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • HeparinanticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • HydralazinevasodilatorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Hydrochlorothiazidethiazide diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • IbuprofenNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Indapamidethiazide diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • IndomethacinNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • InfliximabimmunosuppressantModerate

    Upon initiation or discontinuation of RENFLEXIS in patients being treated with CYP450 substrates with a narrow therapeutic index, monitoring of the effect (e.g., warfarin) or drug concentration (e.g., cyclosporine or theophylline) is recommended and the individual dose of the drug product may be adjusted as needed. (Infliximab label, Drug interactions)

  • Insulin aspartinsulinModerate

    Drugs That May Increase the Risk of Hypoglycemia Drugs: Antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline, pramlintide, salicylates, somatostatin analog (e.g., octreotide), and sulfonamide antibiotics. (Insulin aspart label, Drug interactions)

  • Insulin degludecinsulinModerate

    …May Increase the Risk of Hypoglycemia Drugs: Antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline, pramlintide, salicylates, somatostatin analogs (e.g., octreotide), and sulfonamide antibiotics, GLP-1 receptor agonists, DPP-4 inhibitors, SGLT-2 inhibitors. (Insulin degludec label, Drug interactions)

  • Insulin detemirinsulinModerate

    …May Increase the Risk of Hypoglycemia Drugs: Antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline, pramlintide, salicylates, somatostatin analogs (e.g., octreotide), and sulfonamide antibiotics, GLP-1 receptor agonists, DPP-4 inhibitors, SGLT-2 inhibitors. (Insulin detemir label, Drug interactions)

  • Insulin glargineinsulinModerate

    …May Increase the Risk of Hypoglycemia Drugs: Antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline, pramlintide, salicylates, somatostatin analogs (e.g., octreotide), sulfonamide antibiotics, GLP-1 receptor agonists, DPP-4 inhibitors, and SGLT-2 inhibitors. (Insulin glargine label, Drug interactions)

  • Insulin lisproinsulinModerate

    Clinically Significant Drug Interactions with LYUMJEV Drugs That May Increase the Risk of Hypoglycemia Drugs: Antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, pentoxifylline, pramlintide, salicylates, somatostatin analogs (e.g., octreotide), and sulfonamide antibiotics. (Insulin lispro label, Drug interactions)

  • …with AFREZZA Antidiabetic agents, Angiotensin-Converting Enzyme Inhibitors, Angiotensin II Receptor Blocking Agents, Disopyramide, Fibrates, Fluoxetine, Monoamine Oxidase Inhibitors, Pentoxifylline, Pramlintide, Salicylates, Somatostatin Analogs (e.g., octreotide), and Sulfonamide Antibiotics Prevention or Management Monitor blood glucose more frequently and modify… (Insulin regular (human) label, Drug interactions)

  • Irbesartanangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Irbesartan and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • IsoniazidantibioticModerate

    Theophylline A recent study has shown that concomitant administration of isoniazid and theophylline may cause elevated plasma levels of theophylline, and in some instances a slight decrease in the elimination of isoniazid. (Isoniazid label, Drug interactions)

  • Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Isradipinedihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • KetoprofenNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Labetalolbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Lansoprazoleproton pump inhibitorModerate

    Theophylline Clinical Impact: Increased clearance of theophylline [see Clinical Pharmacology (12.3) ] . (Lansoprazole label, Drug interactions)

  • LeflunomideimmunosuppressantModerate

    In patients taking ARAVA, exposure of drugs metabolized by CYP1A2 (e.g., alosetron, duloxetine, theophylline, tizanidine) may be reduced. (Leflunomide label, Drug interactions)

  • LevocetirizineantihistamineModerate

    There was a small decrease (~16%) in the clearance of cetirizine caused by a 400 mg dose of theophylline. (Levocetirizine label, Drug interactions)

  • LevofloxacinfluoroquinoloneModerate

    However, concomitant administration of other fluoroquinolones with theophylline has resulted in prolonged elimination half-life, elevated serum theophylline levels, and a subsequent increase in the risk of theophylline-related adverse reactions in the patient population. (Levofloxacin label, Drug interactions)

  • Levonorgestrel and ethinyl estradioloral contraceptiveModerate

    Concomitant use with ethinyl estradiol-containing CHCs may increase systemic exposure of other drugs (e.g., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole). (Levonorgestrel and ethinyl estradiol label, Drug interactions)

  • LisinoprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Lofexidinealpha-adrenergic agonistModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Losartanangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Losartan and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • MecamylamineantihypertensiveModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Mefenamic acidNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • MeloxicamNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • MercaptopurineantimetaboliteModerate

    Allopurinol Allopurinol can inhibit the first-pass oxidative metabolism of mercaptopurine by xanthine oxidase, which can lead to an increased risk of mercaptopurine adverse reactions (i.e., myelosuppression, nausea, and vomiting) [see Warnings and Precautions (5.1), Adverse Reactions (6.1)] . (Mercaptopurine label, Drug interactions)

  • Methimazoleantithyroid drugModerate

    Theophylline: Theophylline clearance may decrease when hyperthyroid patients on a stable theophylline regimen become euthyroid; a reduced dose of theophylline may be needed. (Methimazole label, Drug interactions)

  • MethotrexateimmunosuppressantModerate

    Effect of XATMEP on Other Drugs Theophylline Methotrexate may decrease the clearance of theophylline. (Methotrexate label, Drug interactions)

  • MethyldopaantihypertensiveModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Metolazonethiazide diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Metoprololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • MexiletineantiarrhythmicModerate

    Concomitant administration of strong CYP1A2 inhibitors (including e.g., ciprofloxacin or fluvoxamine) may increase the exposure to pentoxifylline (see ADVERSE REACTIONS). (Pentoxifylline label, Drug interactions)

  • MinoxidilvasodilatorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • MoexiprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • NabumetoneNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Nadololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Naltrexone and bupropionopioid antagonistModerate

    …may cause hypoglycemia concomitant administration of medications that may lower the seizure threshold, including other bupropion products, antipsychotics, tricyclic antidepressants, theophylline, systemic steroids Recommendations for Reducing the Risk of Seizure: Clinical experience with bupropion suggests that the risk of seizure may be minimized by adhering to… (Naltrexone and bupropion label, Warnings and precautions)

  • NaproxenNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Nebivololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • NefazodoneantidepressantModerate

    FEV 1 measurements taken when theophylline and nefazodone were coadministered did not differ from baseline dosage (i.e., when theophylline was administered alone). (Nefazodone label, Drug interactions)

  • Nicardipinedihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Nifedipinedihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Nisoldipinedihydropyridine calcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • NitroprussidevasodilatorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Effects of Combined Hormonal Contraceptives on Other Drugs CHCs containing EE may inhibit the metabolism of other compounds (e.g., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole) and increase their plasma concentrations. (Norelgestromin and ethinyl estradiol label, Drug interactions)

  • Norgestimate and ethinyl estradioloral contraceptiveModerate

    Effects of Combined Oral Contraceptives on Other Drugs COCs containing EE may inhibit the metabolism of other compounds (e.g., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole) and increase their plasma concentrations. (Norgestimate and ethinyl estradiol label, Drug interactions)

  • Norgestrel and ethinyl estradioloral contraceptiveModerate

    Effects of Combined Oral Contraceptives on Other Drugs COCs containing EE may inhibit the metabolism of other drugs (e.g., cyclosporine, prednisolone, theophylline, tizanidine, and voriconazole) and increase their plasma concentrations. (Norgestrel and ethinyl estradiol label, Drug interactions)

  • OfloxacinfluoroquinoloneModerate

    This may result in a prolonged half-life for some drugs that are also metabolized by this system (e.g., cyclosporine, theophylline/methylxanthines, warfarin) when coadministered with quinolones. (Ofloxacin label, Drug interactions)

  • Olmesartanangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Olmesartan and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Olmesartan, amlodipine, and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • OxaprozinNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • PerindoprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Phenoxybenzaminealpha blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • PhenytoinanticonvulsantModerate

    John’s wort may vary widely based on preparation. , sucralfate, theophylline Drugs that may either increase or decrease phenytoin serum levels Antiepileptic drugs Phenobarbital, valproate sodium Valproate sodium and valproic acid are similar medications. (Phenytoin label, Drug interactions)

  • Phytonadione (vitamin K1)vitamin KModerate

    Increased prothrombin time has been reported in patients concomitantly treated with pentoxifylline and vitamin K antagonists. (Pentoxifylline label, Drug interactions)

  • Pindololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Pioglitazone and glimepiridethiazolidinedioneModerate

    …intensity of hypoglycemia: oral anti-diabetic medications, pramlintide acetate, insulin, angiotensin converting enzyme (ACE) inhibitors, H2 receptor antagonists, fibrates, propoxyphene, pentoxifylline, somatostatin analogs, anabolic steroids and androgens, cyclophosphamide, phenyramidol, guanethidine, fluconazole, sulfinpyrazone, tetracyclines, clarithromycin, disopyramide,… (Pioglitazone and glimepiride label, Drug interactions)

  • PiroxicamNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Prasugrelantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Prazosinalpha blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • PrimaquineantimalarialModerate

    Effects of Primaquine on the Pharmacokinetics of Other Drugs CYP1A2 Substrates Published clinical and non-clinical reports indicate primaquine inhibits CYP1A2 enzyme activity and thus may lead to increased exposure of CYP1A2 substrate drugs (e.g., duloxetine, alosetron, theophylline and tizanidine) when co-administered with Primaquine phosphate Tablets. (Primaquine label, Drug interactions)

  • Propranololbeta blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Propylthiouracilantithyroid drugModerate

    Theophylline: Theophylline clearance may decrease when hyperthyroid patients on a stable theophylline regimen become euthyroid; a reduced dose of theophylline may be needed. (Propylthiouracil label, Drug interactions)

  • QuinaprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • QuinineantimalarialModerate

    Theophylline or Aminophylline In 20 healthy subjects who received multiple doses of quinine sulfate (648 mg every 8 hours x 7 days) with a single 300 mg oral dose of theophylline, the quinine mean C max and AUC were increased by 13% and 14% respectively. (Quinine label, Drug interactions)

  • RamiprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • RifapentineantibioticModerate

    …Clofibrate Oral Hypoglycemics Sulfonylureas (e.g., glyburide, glipizide) Hormonal Contraceptives/Progestins Ethinyl estradiol, levonorgestrel Immunosuppressants Cyclosporine, tacrolimus Methylxanthines Theophylline Narcotic analgesics Methadone Phosphodiesterase-5 (PDE-5) Inhibitors Sildenafil Thyroid preparations Levothyroxine Tricyclic antidepressants Amitriptyline,… (Rifapentine label, Drug interactions)

  • RitonavirantiretroviralModerate

    Bronchodilator: theophylline ↓ theophylline Increased dosage of theophylline may be required; therapeutic monitoring should be considered. (Ritonavir label, Drug interactions)

  • RivaroxabananticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Sacubitril and valsartanangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • SalsalateNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Spironolactonealdosterone antagonistModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Spironolactone and hydrochlorothiazidealdosterone antagonistModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • SucralfateModerate

    Drug Interactions Some studies have shown that simultaneous sucralfate administration in healthy volunteers reduced the extent of absorption (bioavailability) of single doses of the following: cimetidine, digoxin, fluoroquinolone antibiotics, ketoconazole, l-thyroxine, phenytoin, quinidine, ranitidine, tetracycline, and theophylline. (Sucralfate label, Drug interactions)

  • SulindacNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • TadalafilPDE5 inhibitorModerate

    When tadalafil was administered to subjects taking theophylline, a small augmentation (3 beats per minute) of the increase in heart rate associated with theophylline was observed. (Tadalafil label, Drug interactions)

  • Tamsulosinalpha blockerModerate

    Digoxin and Theophylline Dosage adjustments are not necessary when a tamsulosin hydrochloride capsule is administered concomitantly with digoxin or theophylline [see Clinical Pharmacology ( 12.3 )] . (Tamsulosin label, Drug interactions)

  • Telmisartanangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Telmisartan and amlodipineangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Telmisartan and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Terazosinalpha blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • TerbinafineantifungalModerate

    The influence of terbinafine on the pharmacokinetics of fluconazole, cotrimoxazole (trimethoprim and sulfamethoxazole), zidovudine or theophylline was not considered to be clinically significant. (Terbinafine label, Drug interactions)

  • TeriflunomideimmunosuppressantModerate

    In patients taking AUBAGIO, exposure of drugs metabolized by CYP1A2 (e.g., alosetron, duloxetine, theophylline, tizanidine) may be reduced. (Teriflunomide label, Drug interactions)

  • Ticagrelorantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • TiotropiumanticholinergicModerate

    Concomitant Respiratory Medications SPIRIVA RESPIMAT has been used concomitantly with short-acting and long-acting sympathomimetic (beta-agonists) bronchodilators, methylxanthines, oral and inhaled steroids, antihistamines, mucolytics, leukotriene modifiers, cromones, and anti-IgE treatment without increases in adverse reactions. (Tiotropium label, Drug interactions)

  • Tirofibanantiplatelet agentModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Tizanidinemuscle relaxantModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • TocilizumabimmunosuppressantModerate

    Upon initiation or discontinuation of TOFIDENCE, in patients being treated with these types of medicinal products, perform therapeutic monitoring of effect (e.g., warfarin) or drug concentration (e.g., cyclosporine or theophylline) and the individual dose of the medicinal product adjusted as needed. (Tocilizumab label, Drug interactions)

  • TolmetinNSAIDModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Torsemideloop diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • TrandolaprilACE inhibitorModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Triamterenepotassium-sparing diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Triamterene and hydrochlorothiazidepotassium-sparing diureticModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Valsartanangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Valsartan and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • VareniclineModerate

    • Effect of Smoking Cessation on Other Drugs: Pharmacokinetics or pharmacodynamics of certain drugs (e.g., theophylline, warfarin, insulin) may be altered, necessitating dose adjustment. (Varenicline label, Drug interactions)

  • Verapamilcalcium channel blockerModerate

    Small decreases in blood pressure have been observed in some patients treated with pentoxifylline extended-release tablets; periodic systemic blood pressure monitoring is recommended for patients receiving concomitant antihypertensive therapy. (Pentoxifylline label, Drug interactions)

  • Viloxazinenorepinephrine reuptake inhibitorModerate

    Concomitant administration of strong CYP1A2 inhibitors (including e.g., ciprofloxacin or fluvoxamine) may increase the exposure to pentoxifylline (see ADVERSE REACTIONS). (Pentoxifylline label, Drug interactions)

  • Vitamin KVitamin and mineralModerate

    Increased prothrombin time has been reported in patients concomitantly treated with pentoxifylline and vitamin K antagonists. (Pentoxifylline label, Drug interactions)

  • WarfarinanticoagulantModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • Zafirlukastleukotriene receptor antagonistModerate

    Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

  • ZileutonCYP1A2 inhibitorModerate

    Concomitant administration of strong CYP1A2 inhibitors (including e.g., ciprofloxacin or fluvoxamine) may increase the exposure to pentoxifylline (see ADVERSE REACTIONS). (Pentoxifylline label, Drug interactions)

Minor mentions (28)

  • Acetazolamidecarbonic anhydrase inhibitorMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • AmiodaroneantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • AnagrelideQT-prolonging drugMinor

    CYP1A2 substrates: AGRYLIN demonstrates limited inhibitory activity towards CYP1A2 in vitro and may alter the exposure of concomitant CYP1A2 substrates (e.g., theophylline, fluvoxamine, ondansetron). (Anagrelide label, Drug interactions)

  • Brimonidine and timololalpha-adrenergic agonistMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • Bumetanideloop diureticMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • CarbamazepineanticonvulsantMinor

    Such drugs include the following: Aminophylline, c isplatin, doxorubicin, felbamate, phosphenytoin, methsuximide , phenobarbital, phenytoin, primidone, rifampin and theophylline. (Carbamazepine label, Drug interactions)

  • CidofovirantiviralMinor

    …Probenecid Probenecid is known to interact with the metabolism or renal tubular excretion of many drugs (e.g., acetaminophen, acyclovir, angiotensin-converting enzyme inhibitors, aminosalicylic acid, barbiturates, benzodiazepines, bumetanide, clofibrate, methotrexate, famotidine, furosemide, nonsteroidal anti-inflammatory agents, theophylline, and zidovudine). (Cidofovir label, Drug interactions)

  • Digoxindigitalis glycosideMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • DisopyramideantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • DofetilideantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • Dorzolamide and timololcarbonic anhydrase inhibitorMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • DronedaroneantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • Esmololbeta blockerMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • FlecainideantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • IbutilideantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • IpratropiumanticholinergicMinor

    ATROVENT HFA has been used concomitantly with other drugs, including sympathomimetic bronchodilators, methylxanthines, oral and inhaled steroids commonly used in the treatment of COPD. (Ipratropium label, Drug interactions)

  • Lidocainelocal anestheticMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • Lidocaine and prilocainelocal anestheticMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • Lithiumserotonergic drugMinor

    Acetazolamide, Urea, Xanthine Preparations, Alkalinizing Agents Clinical Impact: Concomitant use can lower serum lithium concentrations by increasing urinary lithium excretion. (Lithium label, Drug interactions)

  • Falsely high readings for theophylline have been reported in an in vitro study, using the Schack and Waxler technique, when therapeutic concentrations of theophylline and probenecid were added to human plasma. (Probenecid label, Drug interactions)

  • Falsely high readings for theophylline have been reported in an in vitro study, using the Schack and Waxler technique, when therapeutic concentrations of theophylline and probenecid were added to human plasma. (Probenecid and colchicine label, Drug interactions)

  • ProcainamideantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • PropafenoneantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • QuinidineantiarrhythmicMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • RepaglinidemeglitinideMinor

    Examples: Antidiabetic agents, ACE inhibitors, angiotensin II receptor blocking agents, disopyramide, fibrates, fluoxetine, monoamine oxidase inhibitors, nonsteroidal anti-inflammatory agents (NSAIDs), pentoxifylline, pramlintide, propoxyphene, salicylates, somatostatin analogs (e.g., octreotide), and sulfonamide antibiotics. (Repaglinide label, Drug interactions)

  • Ropivacainelocal anestheticMinor

    Possible interactions with drugs known to be metabolized by CYP1A2 via competitive inhibition such as theophylline and imipramine may also occur. (Ropivacaine label, Drug interactions)

  • Sotalolbeta blockerMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

  • Timololbeta blockerMinor

    Pentoxifylline extended-release tablets have been used concurrently with antihypertensive drugs, beta blockers, digitalis, diuretics, and antiarrhythmics, without observed problems. (Pentoxifylline label, Drug interactions)

No significant interaction reported (9)

  • AlosetronNo interaction

    The effect on CYP1A2 was explored further in a clinical interaction study with theophylline and no effect on metabolism was observed. (Alosetron label, Drug interactions)

  • FamciclovirantiviralNo interaction

    …Penciclovir No clinically significant alterations in penciclovir pharmacokinetics were observed following single-dose administration of 500 mg famciclovir after pretreatment with multiple doses of allopurinol, cimetidine, theophylline, zidovudine, promethazine, when given shortly after an antacid (magnesium and aluminum hydroxide), or concomitantly with emtricitabine. (Famciclovir label, Drug interactions)

  • Finasteride5-alpha reductase inhibitorNo interaction

    Compounds that have been tested in man have included antipyrine, digoxin, propranolol, theophylline, and warfarin and no clinically meaningful interactions were found. (Finasteride label, Drug interactions)

  • Montelukastleukotriene receptor antagonistNo interaction

    No dose adjustment is needed when SINGULAIR is co-administered with theophylline, prednisone, prednisolone, oral contraceptives, fexofenadine, digoxin, warfarin, gemfibrozil, itraconazole, thyroid hormones, sedative hypnotics, non-steroidal anti-inflammatory agents, benzodiazepines, decongestants, and Cytochrome P450 (CYP) enzyme inducers [see Clinical Pharmacology… (Montelukast label, Drug interactions)

  • NizatidineH2 blockerNo interaction

    Drug Interactions No interactions have been observed between nizatidine and theophylline, chlordiazepoxide, lorazepam, lidocaine, phenytoin, and warfarin. (Nizatidine label, Drug interactions)

  • OlanzapineantipsychoticNo interaction

    Theophylline — Multiple doses of olanzapine did not affect the pharmacokinetics of theophylline or its metabolites. (Olanzapine label, Drug interactions)

  • Olanzapine and fluoxetineantipsychoticNo interaction

    Theophylline — Multiple doses of olanzapine did not affect the pharmacokinetics of theophylline or its metabolites. (Olanzapine and fluoxetine label, Drug interactions)

  • Ropiniroledopamine agonistNo interaction

    Theophylline: Administration of theophylline (300 mg twice daily), a substrate of CYP1A2, did not alter the steady-state pharmacokinetics of ropinirole (2 mg 3 times daily) in 12 patients with Parkinson’s disease. (Ropinirole label, Drug interactions)

  • TiagabineanticonvulsantNo interaction

    Theophylline : A single 10 mg dose of tiagabine did not affect the pharmacokinetics of theophylline at steady state. (Tiagabine label, Drug interactions)

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Not medical advice. Severity reflects the label's wording, not your circumstances. A "major" flag can be routine under supervision and a "minor" one can matter at high doses. Ask a pharmacist.