Diltiazem and Posaconazole interaction
Diltiazem and Posaconazole: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Diltiazem (DILTIAZEM HYDROCHLORIDE in SODIUM CHLORIDE) label · effective 2025-04-15
Effect of other drugs on Diltiazem Cytochrome P450 3A4 Inhibitors/ Inducers Diltiazem is a substrate of the cytochrome P450 3A4 enzyme and inhibitors/inducers may change the pharmacological effect of diltiazem Monitor.
From the Posaconazole (NOXAFIL) label · effective 2026-02-13
Calcium Channel Blockers that are CYP3A4 Substrates Mechanism and Clinical Effect(s) Posaconazole may increase the plasma concentrations of calcium channel blockers that are substrates of CYP3A4.
Prevention or Management Verapamil, Diltiazem, Nifedipine, Nicardipine, Felodipine Monitor frequently for adverse reactions and toxicity with concomitant use of posaconazole with calcium channel blockers that are CYP3A4 substrates.
Dosage reduction of the calcium channel blocker may be needed.
Effects of Noxafil and Noxafil PowderMix on Other Drugs Posaconazole is a strong 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.