Grapefruit and Nifedipine interaction
Grapefruit and Nifedipine: the Nifedipine prescribing label flags 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
Grapefruit juice should be avoided by patients on nifedipine.
…as ketoconazole, fluconazole, itraconazole, clarithromycin, erythromycin (Azithromycin, although structurally related to the class of macrolide antibiotic is void of clinically relevant CYP3A4 inhibition), grapefruit, nefazodone, fluoxetine, saquinavir, indinavir, nelfinavir, and ritonavir may result in increased exposure to nifedipine when co-administered.
Dietary Supplements Grapefruit Juice: In healthy volunteers, a single dose co-administration of 250 mL double strength grapefruit juice with 10 mg nifedipine increased AUC and C max by factors of 1.35 and 1.13, respectively.
Ingestion of repeated doses of grapefruit juice (5 × 200 mL in 12 hours) after administration of 20 mg nifedipine ER increased AUC and C max of nifedipine by a factor of 2.
The intake of grapefruit juice should be stopped at least 3 days prior to initiating patients on nifedipine.
Curated guidance for Grapefruit
Grapefruit juice can raise blood levels of some calcium channel blockers used for blood pressure, which may cause excessive lowering of blood pressure.
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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.