Nirmatrelvir and ritonavir and Tenofovir interaction
Nirmatrelvir and ritonavir and Tenofovir: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Tenofovir (Viread) label · effective 2025-02-18
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.
When coadministered with VIREAD, use atazanavir given with ritonavir.
From the Nirmatrelvir and ritonavir (Paxlovid) label · effective 2026-02-19
Anti-HIV efavirenz, maraviroc, nevirapine, zidovudine, bictegravir/ emtricitabine/ tenofovir ↑ efavirenz ↑ maraviroc ↑ nevirapine ↓ zidovudine ↑ bictegravir ↔ emtricitabine ↑ tenofovir For further information, refer to the respective anti-HIV drugs prescribing information.
Anti-HIV protease inhibitors atazanavir, darunavir, tipranavir ↑ protease inhibitor For further information, refer to the respective protease inhibitors' prescribing information.
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.