drug-food interaction
5 interactions related to drug-food interaction
itraconazole + grapefruit
Grapefruit juice has been shown in healthy-volunteer studies to reduce itraconazole capsule peak concentrations by roughly 35 percent and overall AUC by about 43 percent, likely through changes in gastric pH and intestinal effects that impair the capsule's absorption.
fluconazole + grapefruit
Fluconazole is a moderate inhibitor of CYP3A4 and grapefruit juice inhibits intestinal CYP3A4; the inhibition is additive, which can raise plasma levels of any third drug that depends on CYP3A4 for clearance.
amlodipine + grapefruit
Amlodipine is a CYP3A4 substrate, but unlike other dihydropyridines (felodipine, nisoldipine), its high oral bioavailability and slow elimination mean grapefruit juice does not meaningfully alter its pharmacokinetics in controlled trials. Some product labels and consumer references still list a theoretical interaction.
diltiazem + grapefruit
Grapefruit juice inhibits intestinal CYP3A4 and increases diltiazem exposure (AUC) by roughly 20% in healthy volunteers, with high inter-individual variability. The increase can amplify the drug's negative chronotropic and hypotensive effects.
amiodarone + grapefruit
Grapefruit juice inhibits intestinal CYP3A4, raising oral amiodarone AUC by approximately 50% and peak levels by 84% while abolishing production of its active metabolite N-desethylamiodarone. The FDA-approved Pacerone label explicitly states grapefruit juice should not be consumed during oral amiodarone treatment.