Nifedipine and Rifampin interaction
Nifedipine and Rifampin: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Nifedipine label · effective 2026-02-05
CONTRAINDICATIONS Concomitant administration with strong P450 inducers, such as rifampin, are contraindicated since the efficacy of nifedipine tablets could be significantly reduced.
John’s Wort reduce the bioavailability and efficacy of nifedipine; therefore nifedipine should not be used in combination with strong CYP3A inducers such as rifampin (See CONTRAINDICATIONS ).
The impact of multiple oral doses of 600 mg rifampin on the pharmacokinetics of nifedipine after a single oral dose of 20 mg nifedipine capsule was evaluated in a clinical study.
On study Day 15, a second single oral dose of 20 mg nifedipine capsule was administered together with the last dose of rifampin.
Compared to study Day 1, 14 days pretreatment with rifampin reduced C max and AUC of concomitantly administered nifedipine on average by 95% and 97%, respectively.
From the Rifampin label · effective 2026-05-05
…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…
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.