Warfarin Drug Interactions - Amiodarone, Ciprofloxacin, Erythromycin, Azithromycin, Miconazole, Phenytoin

Increase INR value which increases risk of bleeding
Analgesics (acetaminophen, aspirin, topical salicylates, tramadol)
Antiarrhythimics (amiodraone, propafenone)
Antibiotics (examples include amoxicillin, cephalosporins, isoniazid, fluoroquinolones, macrolides, metronidazole, sulfonamides, telithromycin, tetracyclines)
Anticonvulsants (phenytoin which is biphasic, increase initially and decrease in long term, sodium valproate)
Antidepressants (duloxetine, venlafaxine, SSRI e.g. fluoxetine, fluvoxamine, setraline, paroxetine and citalopram)
Antifungals (itraconazole, fluconazole, ketoconazole, miconazole, voriconazole)
Antihyperlipidemics (fenofibrate, ezetimibe, fluvastatin, gemfibrozil, simvastatin)
Others include allopurinol, cimetidine, oral corticosteroids, proton pump inhibitors and thyroid supplements


Decrease INR value which increase risk of blood clotting
Antibiotics (rifampin)
Antidepressants (trazodone)
Antiepileptics (phenytoin, carbamazepine, phenobarbitone, primodone)
Other include antithyroid agents,cholestyramine