Fosamprenavir and Tenofovir interaction
Fosamprenavir and Tenofovir: the Tenofovir prescribing label flags 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 Tenofovir (Viread) label · effective 2025-02-18
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 TDF, alone or in combination with other antiretrovirals.
Coadministration of VIREAD with certain HIV-1 protease inhibitors or certain drugs to treat HCV increases tenofovir concentrations.
HIV-1 Protease Inhibitor s: atazanavir ↓ atazanavir When coadministered with VIREAD, atazanavir 300 mg should be given with ritonavir 100 mg. lopinavir/ritonavir atazanavir/ritonavir darunavir/ritonavir ↑ tenofovir Monitor patients receiving VIREAD concomitantly with lopinavir/ritonavir, ritonavir-boosted atazanavir, or ritonavir-boosted darunavir for TDF-associated…
…receiving VIREAD concomitantly with EPCLUSA ® (sofosbuvir/velpatasvir) for adverse reactions associated with TDF. ledipasvir/sofosbuvir Monitor patients receiving VIREAD concomitantly with HARVONI ® (ledipasvir/sofosbuvir) without an HIV-1 protease inhibitor/ritonavir or an HIV-1 protease inhibitor/cobicistat combination, for adverse reactions associated with TDF.
In patients receiving VIREAD concomitantly with HARVONI and an HIV-1 protease inhibitor/ritonavir or an HIV-1 protease inhibitor/cobicistat combination, consider an alternative HCV or antiretroviral therapy, as the safety of increased tenofovir concentrations in this setting has not been established.
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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.