Aprepitant and Etonogestrel and ethinyl estradiol interaction
Aprepitant and Etonogestrel and ethinyl estradiol: 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 Aprepitant (CINVANTI) label · effective 2026-04-01
Hormonal Contraceptives : Efficacy of contraceptives may be reduced during and for 28 days following administration of aprepitant.
Risk of Reduced Efficacy of Hormonal Contraceptives Upon coadministration with CINVANTI, the efficacy of hormonal contraceptives may be reduced during administration of and for 28 days following the last dose of CINVANTI [see Clinical Pharmacology (12.3) ] .
Hormonal Contraceptives Clinical Impact Decreased hormonal exposure during administration of and for 28 days after administration of the last dose of aprepitant [see Warnings and Precautions (5.4) , Use in Specific Populations (8.3) , and Clinical Pharmacology (12.3) ] .
Examples birth control pills, skin patches, implants, and certain IUDs CYP2C9 Substrates Warfarin Clinical Impact Decreased warfarin exposure and decreased prothrombin time (INR) [see Warnings and Precautions (5.3) , Clinical Pharmacology (12.3) ] .
From the Etonogestrel and ethinyl estradiol (Etonogestrel/Ethinyl Estradiol) label · effective 2025-02-26
Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include: phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, topiramate, rifabutin, rufinamide, aprepitant, and products containing St.
Concomitant administration of strong or moderate CYP3A4 inhibitors such as itraconazole, voriconazole, fluconazole, grapefruit juice, or ketoconazole may increase plasma estrogen and/or progestin concentrations.
Counsel patients to use a back-up or alternative method of contraception when enzyme inducers are used with CHCs.
Counsel women to use an alternative non-hormonal method of contraception or a back-up method when enzyme inducers are used with Etonogestrel/Ethinyl Estradiol Vaginal Ring, and to continue back-up non-hormonal contraception for 28 days after discontinuing the enzyme inducer to ensure contraceptive reliability.
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.