Warfarin
210 interactions 9 explained in plain English
Also sold as:
Coumadin
Jantoven
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
· Updated Jul 4, 2026
· Editorial policy
· Data sources
Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →
Most serious with:
Defibrotide Injection
Cefixime
Cyclophosphamide
Penicillin V Potassium
Enasidenib
Ofloxacin Otic
Moderate
Warfarin Lactulose Cholac® Elevated International Normalized Ratio serum values with potentiation of anticoagulation effects Details Warfarin Lansoprazole Prevacid Elevations in International Normalized Ratio serum values and potentiation of anticoagulation effects Details Warfarin Levothyroxine Ermeza Increased response to warfarin therapy Details Warfarin Lovastatin Altocor® An increased INR and increased risk of bleeding Details Warfarin Mesalamine Apriso Decreased warfarin efficacy Details Warfarin Mesalamine Rectal Canasa Decreased warfarin efficacy Details Warfarin Methimazole Felanorm Decreased anticoagulant effectiveness Details Warfarin Niacin Endur-Acin Increased risk of bleeding Details Warfarin Nilutamide Nilandron An increased risk of bleeding DetailsNo interactions on this page match that filter — try the next page or clear the filter.
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