Does Rifampin Interact With Warfarin?

The label advises avoiding this combination or using it only under close medical supervision. Talk to your prescriber or pharmacist before combining them.

Interactions like this one can happen when two medicines have overlapping effects, or when one changes how the other is absorbed, broken down, or cleared from the body. Rifampin is a rifamycin antibiotic (strong cyp3a4 inducer) and Warfarin is a vitamin k antagonist anticoagulant; together they are documented as a major interaction. How much this matters depends on your dose, your other medications, and your overall health.

If you have been prescribed both Rifampin and Warfarin, do not start, stop, or change either medication on your own — some medicines are unsafe to stop suddenly. Tell your prescriber and pharmacist that you take both so they can decide whether the combination is right for you, adjust the dose, monitor you more closely, or suggest an alternative.

Telaprevir Decrease AUC by 92% Systemic Hormonal Contraceptives Prevention or Management: Advise patients to change to non-hormonal methods of birth control during rifampin therapy Estrogens Decrease exposure Progestins Anticonvulsants Phenytoin Administered with rifampin 450 mg daily Decrease exposure Antiarrhythmics Disopyramide Decrease exposure Mexiletine Decrease exposure Quinidine Decrease exposure Propafenone Decrease AUC by 50%–67% Tocainide Decrease exposure Antiestrogens Tamoxifen D…

Source: FDA structured product labeling (set_id 036ab68e-5085-4edc-bd83-784b43d64eab).