Etonogestrel is a medication which is used as a means of birth control for women. It is available as an implant placed under the skin of the upper arm under the brand names Nexplanon and Implanon. It is a synthetic progestin and the active metabolite of desogestrel, formulated as a single subdermal rod containing 68 mg of etonogestrel that releases a low sustained dose systemically for up to three years; pharmacologically it binds the progesterone receptor to inhibit ovulation, increases cervical mucus viscosity and induces endometrial changes that reduce the likelihood of implantation, and it is absorbed from the subdermal matrix, metabolized primarily by hepatic cytochrome P450 enzymes to hydroxylated and conjugated metabolites and eliminated in urine and feces, with plasma levels maintained at contraceptive concentrations throughout the labeled duration when the implant is correctly placed.
Parent: Etonogestrel
![(8S,9S,10R,13S,14S,17S)-3-ethoxy-13-ethyl-11-methylene-17-((trimethylsilyl)ethynyl)-2,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-ol](https://veeprho.com/wp-content/uploads/2022/10/8S-9S-10R-13S-14S-17S-3-ethoxy-13-ethyl-11-methylene-17-trimethylsilyl-ethynyl-2-7-8-9-10-11-12-13-14-15-16-17-dodecahydro-1H-cyclopenta-a-phenanthren-17-ol.png "(8S,9S,10R,13S,14S,17S)-3-ethoxy-13-ethyl-11-methylene-17-((trimethylsilyl)ethynyl)-2,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-ol")
Parent: Etonogestrel
Parent: Etonogestrel
Parent: Etonogestrel
Parent: Etonogestrel
Parent: Etonogestrel
Parent: Etonogestrel
Quality control and regulatory specifications for etonogestrel focus on related steroidal process impurities, oxidative and hydrolytic degradation products, stereoisomeric epimers and residual starting materials, plus nonsteroidal contaminants such as solvents and elemental impurities; manufacturers commonly apply stability indicating HPLC or LC-MS assays and follow ICH guidance so that reporting thresholds are typically around 0.05 percent by weight, individual related-substance limits are commonly set in the range of 0.1 to 0.5 percent by weight, and total impurities are usually controlled to within approximately 0.5 to 2.0 percent depending on the monograph and risk assessment, with specific monitored related compounds including residual desogestrel, 3-ketodesogestrel derivatives, stereochemical epimers, oxidized 17-hydroxy or 3-oxo derivatives and low level process byproducts; residual solvents are controlled per ICH Q3C and elemental impurities per ICH Q3D, and identification and quantitation are performed by validated HPLC-UV, UHPLC-MS, GC-MS and complementary techniques such as NMR when necessary.
Etonogestrel is a synthetic progestogen, also called a progestin, that mimics the action of natural progesterone at progesterone receptors.
Both are synthetic progestins but they differ in chemical structure, pharmacokinetic properties and typical uses; etonogestrel is commonly used in a slow release subdermal implant and is the active metabolite of desogestrel, while levonorgestrel is used in oral contraceptives, intrauterine systems and emergency contraception and has different receptor binding and metabolic profiles leading to different dosing and delivery formats.
Implanon contains the progestin etonogestrel and is therefore a progesterone class medication; it does not contain estrogen.
Etonogestrel frequently alters menstrual bleeding patterns and many users experience reduced bleeding or amenorrhea over time, but effects are variable and some users will continue to have irregular bleeding, spotting or return of regular menses depending on individual response.
