The effect of rifampin on serum etonogestrel concentrations and biomarkers of ovulation among contraceptive implant users: A pharmacokinetic and pharmacodynamic study
Lazorwitz A, Sheeder J, Teal S. The effect of rifampin on serum etonogestrel concentrations and biomarkers of ovulation among contraceptive implant users: A pharmacokinetic and pharmacodynamic study. Contraception 2023, 123: 110035. PMID: 36997081, PMCID: PMC10461170, DOI: 10.1016/j.contraception.2023.110035.Peer-Reviewed Original ResearchConceptsContraceptive implant usersSerum etonogestrel concentrationsStrong CYP3A inducersENG implant usersEtonogestrel concentrationsMedian ageImplant usersCYP3A inducersP4 concentrationsMedian body mass indexSerum E2 concentrationsBody mass indexSignificant decreaseParticipants' median ageSuppression of ovulationSerum P4 concentrationsEffect of rifampinDrug-drug interactionsLiquid chromatography-mass spectrometry assayOnly short exposuresWilcoxon signed-rank testBaseline E2Rifampin 600Rifampin exposureRifampin therapy