Efavirenz and Nisoldipine interaction
Efavirenz and Nisoldipine: 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 Nisoldipine (Sular) label · effective 2026-03-12
CYP3A4 inhibitors and inducers : SULAR is substrate of CYP3A4 and coadministration of SULAR with any known inducer or inhibitor of CYP3A4 should be avoided in general.
From the Efavirenz label · effective 2024-03-31
Calcium channel blockers: Diltiazem Others (e.g., felodipine, nicardipine, nifedipine, verapamil) ↓ diltiazem * ↓ desacetyl diltiazem * ↓ N-monodesmethyl diltiazem * ↓ calcium channel blocker Diltiazem dose adjustments should be guided by clinical response (refer to the full prescribing information for diltiazem).
When coadministered with efavirenz, dosage adjustment of calcium channels blocker may be needed and should be guided by clinical response (refer to the full prescribing information for the calcium channel blocker).
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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.