Atazanavir and Emtricitabine and tenofovir interaction
Atazanavir and Emtricitabine and tenofovir: 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…
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 .
…the components of DESCOVY, no clinically significant drug interactions have been either observed or are expected when DESCOVY is combined with the following antiretroviral agents: atazanavir with ritonavir, atazanavir with cobicistat (in those weighing ≥35 kg), darunavir with ritonavir or cobicistat, dolutegravir, efavirenz, ledipasvir, lopinavir/ritonavir, maraviroc,…
From the Atazanavir (REYATAZ) label · effective 2024-12-05
In a clinical study, saquinavir 1200 mg coadministered with REYATAZ 400 mg and tenofovir DF 300 mg (all given once daily), and nucleoside analogue reverse transcriptase inhibitors did not provide adequate efficacy [see Clinical Studies (14.2) ] . indinavir Coadministration of REYATAZ with indinavir is contraindicated.
REYATAZ is not recommended for pregnant patients during the second and third trimester taking REYATAZ with both tenofovir DF and an H2RA.
Nucleotide Reverse Transcriptase Inhibitors: tenofovir disoproxil fumarate (DF) ↓ atazanavir ↑ tenofovir When coadministered with tenofovir DF in adults, it is recommended that REYATAZ 300 mg be given with ritonavir 100 mg and tenofovir DF 300 mg (all as a single daily dose with food).
Higher tenofovir concentrations could potentiate tenofovir-associated adverse reactions, including renal disorders.
Patients receiving REYATAZ and tenofovir DF should be monitored for tenofovir-associated adverse reactions.
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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.