Ensuring Safe Use of Isotretinoin

For individuals with severe acne, isotretinoin is a first-line therapy. As this agent is both a cytochrome P-450 enzyme inducer and a potent teratogen, researchers conducted a pilot study to evaluate whether isotretinoin lowers serum concentrations of etonogestrel (the progestin used in the contraceptive implant, vaginal ring, and some oral contraceptives) in a clinically relevant fashion.

Among eight healthy reproductive-age women using an etonogestrel contraceptive implant, serum etonogestrel concentrations remained above the level needed to suppress ovulation (>90 pg/mL) during isotretinoin coadministration, with no significant changes from baseline and no reported pregnancies throughout 9 weeks of follow-up.