MedlinePlus a604032 Metabolism CAS ID 54048-10-1 | ATC code G03AC08 (WHO) Molar mass 324.457 g/mol | |
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AHFS/Drugs.com Multum Consumer Information Routes of
administration Subdermal as slow-release implant Legal status AU: S4 (Prescription only)
UK: POM (Prescription only)
US: ℞-only
In general: ℞ (Prescription only) | ||
Etonogestrel is a steroidal progestin used in hormonal contraceptives, most notably the etonogestrel contraceptive implant (Nexplanon and Implanon) and the contraceptive vaginal ring (NuvaRing).
It was first introduced, as Implanon in Indonesia, in 1998, and was subsequently marketed in the United Kingdom shortly thereafter and in the United States in 2006. Etonogestrel is less androgenic than levonorgestrel and norethisterone, and it does not cause a decrease in sex hormone-binding globulin levels, but it is still associated with acne in up to 13% of patients when used as an implant, though this only accounts for 1% of premature removals.
Etonogestrel is the active metabolite of the inactive prodrug desogestrel, one of two third-generation progestins found in some epidemiological studies of combined oral contraceptive pills to be associated with a higher risk of venous thrombosis than combined oral contraceptive pills containing certain second-generation progestins. Because hormones are released continuously from NuvaRing, peak and total estrogen and progestin doses are significantly lower than with combined oral contraceptives, although it is not known whether this lowers the risk of blood clots. It is effective within the first 8 hours of insertion.