Table 1. Drug, Food, and Dietary Supplement Interactions With Warfarin
Level of Causation
Potentiation Highly probable
Anti-infectives
Ciprofloxacin Cotrimoxazole Erythromycin Fluconazole Isoniazid Metronidazole Miconazole oral gel Miconazole vaginal suppository Voriconazole
Probable
Amoxicillin/ clavulanate
Azithromycin Clarithromycin Itraconazole Levofloxacin Ritonavir Tetracycline
Possible
Amoxicillin Amoxicillin/ tranexamic rinse
Chloramphenicol Gatifloxacin Miconazole topical gel
Nalidixic acid Norfloxacin Ofloxacin Saquinavir Terbinafine
Highly improbable
Inhibition Highly probable
Cefamandole Cefazolin Sulfisoxazole
Griseofulvin Nafcillin Ribavirin Rifampin
Probable
Dicloxacillin Ritonavir
Bezafibrate Heparin
Cholestyramine Cardiovascular
Amiodarone Clofibrate Diltiazem Fenofibrate Propafenone Propranolol Sulfinpyrazone (biphasic with later inhibition)
Aspirin Fluvastatin Quinidine Ropinirole Simvastatin
Amiodarone- induced toxicosis
Disopyramide Gemfibrozil Metolazone
Analgesics, Anti-inflammatories, and Immunologics
Phenylbutazone Piroxicam
Acetaminophen Aspirin Celecoxib Dextropropoxyphene Interferon Tramadol
Celecoxib Indomethacin Leflunomide Propoxyphene Rofecoxib Sulindac Tolmetin Topical salicylates
Levamisole Methylprednisolone Nabumetone
Mesalamine
Bosentan
Azathioprine
