Aprepitant and Levonorgestrel and ethinyl estradiol interaction
Aprepitant and Levonorgestrel 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 Levonorgestrel and ethinyl estradiol (Tyblume) label · effective 2026-08-27
Enzyme inducers (e.g., CYP3A4) : May decrease the effectiveness of TYBLUME or increase breakthrough bleeding.
Metabolic Enzyme Inducers Clinical effect Concomitant use of CHCs with metabolic enzyme inducers may decrease the plasma concentrations of the estrogen and/or progestin component of CHCs [see Clinical Pharmacology (12.3) ] .
CYP3A inhibitors such as itraconazole, voriconazole, fluconazole, grapefruit juice The effect of grapefruit juice on CYP3A4 enzymes (e.g., strong vs. moderate inhibition) depends on its brand, concentration, and preparation. , or ketoconazole may increase systemic exposure of the estrogen and/or progestin component of CHCs.
Examples Aprepitant, barbiturates, bosentan, carbamazepine, efavirenz, felbamate, griseofulvin, oxcarbazepine, phenytoin, rifampin, primidone, phenylbutazone, rifabutin, rufinamide, topiramate, products containing St.
Counsel patients to use a back-up or alternative method of contraception when enzyme inducers are used with TYBLUME.
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.