Nevirapine and Ritonavir interaction
Nevirapine and Ritonavir: 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 Nevirapine label · effective 2026-07-15
Fosamprenavir ↓ Amprenavir ↑ Nevirapine Co-administration of nevirapine and fosamprenavir without ritonavir is not recommended.
Female gender and higher CD4 + cell counts at initiation of therapy place patients at increased risk; women with CD4 + cell counts greater than 250 cells/mm 3 , including pregnant women receiving nevirapine in combination with other antiretrovirals for the treatment of HIV-1 infection, are at the greatest risk.
Fosamprenavir/Ritonavir ↓ Amprenavir ↑ Nevirapine No dosing adjustments are required when nevirapine is co-administered with 700/100 mg of fosamprenavir/ritonavir twice daily.
Lopinavir/Ritonavir ↓ Lopinavir Dosing in adult patients: A dose adjustment of lopinavir/ritonavir to 500/125 mg tablets twice daily or 533/133 mg (6.5 mL) oral solution twice daily is recommended when used in combination with nevirapine.
Saquinavir/Ritonavir The interaction between nevirapine and saquinavir/ritonavir has not been evaluated The appropriate doses of the combination of nevirapine and saquinavir/ritonavir with respect to safety and efficacy have not been established.
From the Ritonavir (Norvir) label · effective 2026-07-23
Hepatotoxicity Hepatic transaminase elevations exceeding 5 times the upper limit of normal, clinical hepatitis, and jaundice have occurred in patients receiving NORVIR alone or in combination with other antiretroviral drugs (see Table 2).
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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.