Emtricitabine and tenofovir and Ritonavir interaction
Emtricitabine and tenofovir 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 Emtricitabine and tenofovir (DESCOVY) label · effective 2026-07-07
Drug Interactions Concomitant Drug Class: Drug Name Effect on Concentration ↓=Decrease Clinical Comment ↑= Increase Antiretroviral Agents: Protease Inhibitors (PI) tipranavir/ritonavir ↓ TAF Coadministration with DESCOVY is not recommended. atazanavir/cobicistat ↑ TAF Coadministration with DESCOVY in pediatric patients weighing 14 to < 35 kg is not recommended…
Coadministration of DESCOVY with other drugs that inhibit P-gp and BCRP may increase the absorption and plasma concentration of TAF.
Lactic Acidosis/Severe Hepatomegaly with Steatosis Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogs, including emtricitabine, a component of DESCOVY, and tenofovir DF, another prodrug of tenofovir, alone or in combination with other antiretrovirals.
TAF is a weak inhibitor of CYP3A in vitro .
TAF is not an inhibitor or inducer of CYP3A in vivo .
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).
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.