Moderate
Established
Description
Cyclosporine inhibits CYP3A4-mediated amlodipine metabolism, increasing amlodipine plasma concentrations and the risk of pronounced vasodilation and peripheral edema.
Mechanism
Amlodipine is a CYP3A4 substrate; cyclosporine's CYP3A4 inhibition reduces amlodipine clearance, potentially increasing amlodipine AUC by 30–50%.
Clinical Significance
Peripheral edema, excessive hypotension, and reflex tachycardia may occur; the interaction is clinically relevant in transplant patients commonly prescribed both drugs.
Management
Start amlodipine at a low dose in cyclosporine-treated patients; monitor for edema and hypotension; reduce amlodipine dose if adverse effects occur.