What is Mesterolone?
Mesterolone is an oral DHT-derived androgen with weak anabolic activity. It is not converted to oestrogen. Medically it is used for androgen deficiency in men due to reduced testicular function.
How well studied is Mesterolone?
An older medicine with limited modern evidence; no reliable studies on use in strength sports.
What side effects and risks does Mesterolone have?
Per the patient leaflet, among others acne, hair loss, headache, abdominal complaints and prolonged erections (priapism); contraindicated in prostate cancer and liver tumours. The leaflet explicitly warns that misuse for bodybuilding carries serious cardiovascular, liver and mental-health risks. Like all androgens it can affect the hormone axis.
Is Mesterolone approved in Germany?
In short: yes. Approved as a prescription medicine in some EU countries (e.g. Proviron in Belgium); use only under medical supervision. WADA S1. Under Germany's Anti-Doping Act (AntiDopG), trading and supplying are prohibited, and even acquiring or possessing a “non-small quantity” (set by the Doping Substances Quantity Ordinance) is a criminal offence – including for recreational athletes and for personal use. Black-market products are frequently counterfeit, mislabelled or contaminated.
Sources
- Proviron 25 mg – Gebrauchsinformation (FAMHP Belgien)
- WADA-Verbotsliste, Klasse S1 Anabole Wirkstoffe (Übersicht drugs.com)
Note: We deliberately do not list any doses here. For approved medicines, your doctor sets the dose; for unapproved substances there is no reliable information.