Gestrinone

Class: 19-nortestosterone derivative, the same chemical family as nandrolone and trenbolone. Binds progesterone, androgen and estrogen receptors in endometrial tissue. WADA lists it under S1 anabolic agents, prohibited at all times.

Regulatory status:

• Australia: Schedule 4 and Appendix D clause 5 (anabolic and androgenic steroidal agents). The old Dimetriose ARTG entry shows as cancelled
• Brazil: advertising banned (Anvisa, Dec 2021), listed as a C5 anabolic, and compounded hormonal implants suspended by Anvisa in Oct 2024
• USA: not FDA approved. Tetrahydrogestrinone (THG), its hydrogenated derivative, is a named anabolic steroid under US law

Clinical dose (endometriosis, not a recommendation):

• Oral: 2.5mg twice a week for 6 months. 1.25mg twice a week looked similar in two small trials, though a third (Dawood 1997) found 2.5mg more effective
• Implant: an 85mg bioabsorbable pellet is in a Brazilian trial (GLADE). Compounded "beauty chip" doses are not standardised

Key Notes:

• Evidence for endometriosis is low to very low certainty (Cochrane 2026). No clear difference from danazol or leuprorelin in small trials; Cochrane suggests it may be less effective than leuprorelin for period pain
• Hirsutism was more common than on danazol (OR 2.63)
• No published data on haematocrit, glucose or implant removal timelines
• Total testosterone reads low because SHBG collapses. Use free testosterone
• No studies support its use for lipedema or weight loss

Monitoring: lipid panel with ApoB, SHBG, total and free testosterone, ALT/AST and full blood count at baseline, 6-8 weeks and every 3 months. Use reliable contraception: it is an androgen and must not be used in pregnancy.

Full evidence review and the labs to run: Does gestrinone work for endometriosis?.