Home›Warfarin Sodium

Warfarin Sodium

Also known as: Warfarin Sodium

Route: Oral

74 interactions on record⛔ Black Box Warning

Warfarin Sodium has 74 known drug interactions based on U.S. FDA drug labeling data. 55 are classified as major interactions requiring close medical supervision. Notable interactions include combinations with Acyclovir, Allopurinol, Alprazolam. Patients taking Warfarin Sodium should inform their healthcare provider of all current medications — including over-the-counter drugs and supplements — to avoid potentially harmful combinations. Data sourced from OpenFDA and the NIH National Library of Medicine.

Total: 74
Major: 55
Moderate: 3

Major (55)

Warfarin Sodium + Acyclovir— CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Allopurinol— CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Alprazolam— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Amiodarone— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Amlodipine— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Amprenavir— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Aprepitant— CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Atazanavir— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Atorvastatin— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Bicalutamide— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Bosentan— CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Caffeine— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Capecitabine— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Carbamazepine— CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Cilostazol— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Cimetidine— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Ciprofloxacin— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Clarithromycin— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Conivaptan— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Cotrimoxazole— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Cyclosporine— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Darunavir— CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Disulfiram— CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Enoxacin— CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Etravirine— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Famotidine— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Fluconazole— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Fluvastatin— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Fluvoxamine— CYP2C9 and CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Heparin Sodium— Heparin may prolong prothrombin time; at least 5 hours after IV or 24 hours after SC heparin dose should elapse before b…
Warfarin Sodium + Methoxsalen— CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Metronidazole— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Mexiletine— CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Miconazole— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Montelukast— CYP1A2 and CYP3A4 inducer that decreases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Moricizine— CYP1A2 inducer that decreases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Norfloxacin— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Omeprazole— CYP1A2 and CYP3A4 inducer that decreases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Oral Contraceptives— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Oxandrolone— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Phenobarbital— CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Phenylpropanolamine— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Phenytoin— CYP1A2 and CYP3A4 inducer that decreases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Propafenone— CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Propranolol— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Rifampin— CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Sulfinpyrazone— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Terbinafine— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Thiabendazole— CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.
Warfarin Sodium + Ticlopidine— CYP1A2 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Tigecycline— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Verapamil— CYP1A2 inhibitor that increases warfarin effect and INR; requires close monitoring.
Warfarin Sodium + Voriconazole— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Zafirlukast— CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.
Warfarin Sodium + Zileuton— CYP1A2 inhibitor that increases warfarin effect and INR; requires close monitoring.

Moderate (3)

Warfarin Sodium + Acetaminophen— Chronic oral acetaminophen use at 4000 mg/day increases INR in some patients stabilized on warfarin. More frequent INR a…
Warfarin Sodium + Acetaminophen And Codeine Phosphate— Chronic acetaminophen use at 4000 mg/day may increase INR in patients stabilized on warfarin. More frequent INR assessme…
Warfarin Sodium + Fondaparinux Sodium— Concomitant use did not significantly affect pharmacokinetics/pharmacodynamics in clinical studies. Monitor for hemorrha…

Warfarin Sodium + Acyclovir⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Allopurinol⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Alprazolam⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Amiodarone⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Amlodipine⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Amprenavir⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Aprepitant⚠️Major

CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Atazanavir⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Atorvastatin⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Bicalutamide⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Bosentan⚠️Major

CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Caffeine⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Capecitabine⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Carbamazepine⚠️Major

CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Cilostazol⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Cimetidine⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Ciprofloxacin⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Clarithromycin⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Conivaptan⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Cotrimoxazole⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Cyclosporine⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Darunavir⚠️Major

CYP3A4 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Disulfiram⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Enoxacin⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Etravirine⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Famotidine⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Fluconazole⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Fluvastatin⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Fluvoxamine⚠️Major

CYP2C9 and CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Heparin Sodium⚠️Major

Heparin may prolong prothrombin time; at least 5 hours after IV or 24 hours after SC heparin dose should elapse before blood draw for valid PT.

Warfarin Sodium + Methoxsalen⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Metronidazole⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Mexiletine⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Miconazole⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Montelukast⚠️Major

CYP1A2 and CYP3A4 inducer that decreases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Moricizine⚠️Major

CYP1A2 inducer that decreases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Norfloxacin⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Omeprazole⚠️Major

CYP1A2 and CYP3A4 inducer that decreases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Oral Contraceptives⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Oxandrolone⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Phenobarbital⚠️Major

CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Phenylpropanolamine⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Phenytoin⚠️Major

CYP1A2 and CYP3A4 inducer that decreases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Propafenone⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Propranolol⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Rifampin⚠️Major

CYP2C9 inducer that decreases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Sulfinpyrazone⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Terbinafine⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Thiabendazole⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close INR monitoring.

Warfarin Sodium + Ticlopidine⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Tigecycline⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Verapamil⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Voriconazole⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Zafirlukast⚠️Major

CYP2C9 inhibitor that increases warfarin effect and INR; requires closer INR monitoring.

Warfarin Sodium + Zileuton⚠️Major

CYP1A2 inhibitor that increases warfarin effect and INR; requires close monitoring.

Warfarin Sodium + Acetaminophen🟡Moderate

Chronic oral acetaminophen use at 4000 mg/day increases INR in some patients stabilized on warfarin. More frequent INR assessment may be appropriate during concurrent use.

Warfarin Sodium + Acetaminophen And Codeine Phosphate🟡Moderate

Chronic acetaminophen use at 4000 mg/day may increase INR in patients stabilized on warfarin. More frequent INR assessment may be appropriate.

Warfarin Sodium + Fondaparinux Sodium🟡Moderate

Concomitant use did not significantly affect pharmacokinetics/pharmacodynamics in clinical studies. Monitor for hemorrhage risk if co-administered.

Warfarin Sodium + Erythromycinℹ️Unknown

Table 2: Examples of CYP450 Interactions with Warfarin Enzyme Inhibitors Inducers CYP2C9 amiodarone, capecitabine, cotrimoxazole, etravirine, fluconazole, fluvastatin, fluvoxamine, metronidazole, miconazole, oxandrolone, sulfinpyrazone, tigecycline, voriconazole, zafirlukast aprepitant, bosentan, carbamazepine, phenobarbital, rifampin CYP1A2 acyclovir, allopurinol, caffeine, cimetidine, ciprofloxacin, disulfiram, enoxacin, famotidine, fluvoxamine, methoxsalen, mexiletine, norfloxacin, oral contraceptives, phenylpropanolamine, propafenone, propranolol, terbinafine, thiabendazole, ticlopidine, verapamil, zileuton montelukast, moricizine, omeprazole, phenobarbital, phenytoin, cigarette smoking CYP3A4 alprazolam, amiodarone, amlodipine, amprenavir, aprepitant, atorvastatin, atazanavir, bicalutamide, cilostazol, cimetidine, ciprofloxacin, clarithromycin, conivaptan, cyclosporine, darunavir/ritonavir, diltiazem, erythromycin, fluconazole, fluoxetine, fluvoxamine, fosamprenavir, imatinib, indinavir, isoniazid, itraconazole, ketoconazole, lopinavir/ritonavir, nefazodone, nelfinavir, nilotinib, oral contraceptives, posaconazole, ranitidine, ranolazine, ritonavir, saquinavir, telithromycin, tipranavir, voriconazole, zileuton armodafinil, amprenavir, aprepitant, bosentan, carbamazepine, efavirenz, etravirine, modafinil, nafcillin, phenytoin, pioglitazone, prednisone, rifampin, rufinamide 7.3 Drugs that Increase Bleeding Risk Examples of drugs known to increase the risk of bleeding are presented in Table 3 .

Warfarin Sodium + Fosamprenavirℹ️Unknown

Warfarin Sodium + Imatinibℹ️Unknown

Warfarin Sodium + Indinavirℹ️Unknown

Warfarin Sodium + Itraconazoleℹ️Unknown

Warfarin Sodium + Ketoconazoleℹ️Unknown

Warfarin Sodium + Lopinavirℹ️Unknown

Warfarin Sodium + Nafcillinℹ️Unknown

Warfarin Sodium + Nelfinavirℹ️Unknown

Warfarin Sodium + Nilotinibℹ️Unknown

Warfarin Sodium + Posaconazoleℹ️Unknown

Warfarin Sodium + Ritonavirℹ️Unknown

Warfarin Sodium + Rufinamideℹ️Unknown

Warfarin Sodium + Saquinavirℹ️Unknown

Warfarin Sodium + Telithromycinℹ️Unknown

Warfarin Sodium + Tipranavirℹ️Unknown

Data sourced from U.S. FDA drug labeling via openFDA and the NIH National Library of Medicine. For informational purposes only. Always consult your pharmacist or physician.