Felodipine and Itraconazole interaction
Felodipine and Itraconazole: 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 Itraconazole (Tolsura) label · effective 2025-04-23
Concomitant administration of TOLSURA and felodipine or nisoldipine is contraindicated [see Contraindications (4.1) , Drug Interactions (7.1) and Adverse Reactions (6.2) ] 5.2 Hepatotoxicity Itraconazole has been associated with cases of serious hepatotoxicity, including liver failure and death.
Calcium Channel Blockers Felodipine Nisoldipine Contraindicated during and 2 weeks after TOLSURA treatment.
Calcium channel blockers can have negative inotropic effects which may be additive to those of itraconazole.
Therefore, when co-administering itraconazole and calcium channel blockers, monitor carefully for signs and symptoms of CHF during treatment due to an increased risk of CHF.
Diltiazem Other dihydropyridines Verapamil Monitor for adverse reactions.
From the Felodipine label · effective 2026-06-23
The following specific interactions have been reported: Itraconazole - Coadministration of another extended-release formulation of felodipine with itraconazole resulted in approximately 8-fold increase in the AUC, more than 6-fold increase in the C max , and 2-fold prolongation in the half-life of felodipine.
Coadministration of CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, erythromycin, grapefruit juice, cimetidine) with felodipine may lead to several-fold increases in the plasma levels of felodipine, either due to an increase in bioavailability or due to a decrease in metabolism.
Caution should be used when CYP3A4 inhibitors are coadministered with felodipine.
Drug Interactions CYP3A4 Inhibitors - Felodipine is metabolized by CYP3A4.
These effects have been observed with coadministration of itraconazole (a potent CYP3A4 inhibitor).
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.