Conjugated estrogens and bazedoxifene and Elvitegravir, cobicistat, emtricitabine, and tenofovir interaction
Conjugated estrogens and bazedoxifene and Elvitegravir, cobicistat, emtricitabine, 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 Conjugated estrogens and bazedoxifene (Duavee) label · effective 2026-07-31
Concomitant administration of itraconazole, a strong CYP3A4 inhibitor, with DUAVEE, resulted in increases in bazedoxifene exposure (40%) and, to a lesser extent, conjugated estrogens exposure (9% for baseline-adjusted total estrone, 5% for total equilin), compared to DUAVEE alone [see Pharmacokinetics (12.3) ] .
From the Elvitegravir, cobicistat, emtricitabine, and tenofovir (Genvoya) label · effective 2025-02-03
Hormonal Contraceptives: drospirenone/ethinyl estradiol levonorgestrel norgestimate/ethinyl estradiol ↑ drospirenone ↑ norgestimate ↑ levonorgestrel ↓ ethinyl estradiol Additional or alternative non-hormonal forms of contraception should be considered when estrogen based contraceptives are coadministered with GENVOYA.
The potential risks and benefits associated with coadministration of norgestimate/ethinyl estradiol with GENVOYA should be considered, particularly in patients who have risk factors for these events.
The effect of GENVOYA on other hormonal contraceptives (e.g., contraceptive patch, contraceptive vaginal ring, or injectable contraceptives) or oral contraceptives containing progestogens other than drospirenone, levonorgestrel, or norgestimate has not been studied; therefore, alternative (non-hormonal) methods of contraception can be considered.
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.