Rifampin and Verapamil interaction
Rifampin and Verapamil: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Rifampin (Rifadin IV) label · effective 2026-05-27
…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…
…exposure Benzodiazepines Diazepam , Administered with rifampin 1200 mg daily Decrease exposure Benzodiazepine-related drugs Zopiclone Decrease AUC by 82% Zolpidem Decrease AUC by 73% Calcium Channel Blockers Diltiazem Decrease exposure Nifedipine Rifampin 1200 mg administered as a single oral dose 8 hours before administering a single oral dose of nifedipine 10…
From the Verapamil (Verapamil Hydrochloride) label · effective 2025-03-25
Rifampin Therapy with rifampin may markedly reduce oral verapamil bioavailability.
CYP3A4 inducers decrease verapamil levels ( 7.1 )
Inducers of CYP3A4 (e.g., rifampin) have caused a lowering of plasma levels of verapamil.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.