Methasterone
2α,17α-dimethyl-5α-androstan-17β-ol-3-one. Originally synthesized in the 1950s by Syntex but never marketed. Re-emerged in 2005 as an 'over-the-counter' designer steroid. Extremely potent oral — mg-for-mg one of the strongest available. No aromatization, no estrogenic activity. Very hepatotoxic despite mild androgenic profile.
Mechanism of Action
DHT-derived — cannot aromatize or 5α-reduce further. 2α-methyl modification dramatically increases anabolic potency. 17α-methylation ensures oral bioavailability at the cost of significant hepatotoxicity. No SHBG binding interaction of note. Very high 3β-HSD activity may partly explain its insulin resistance reports.
Typical Dosing
⚠ Warning Flags
- •Severe hepatotoxicity — liver transplants documented
- •High insulin resistance risk — blood glucose monitoring recommended
- •Marked LDL elevation, HDL suppression
- •Never exceed 3–4 weeks
Effect Profile
Side Effect Profile
Research Studies
Detection of designer steroids including methasterone in dietary supplements
Geyer H, et al. · 2008
Methasterone was detected in over-the-counter supplements marketed to athletes; case reports simultaneously documented severe drug-induced liver injury (DILI) requiring hospitalization — establishing its hepatotoxic risk profile.
Hepatotoxicity associated with dietary supplements containing anabolic steroids
Kafrouni MI, et al. · 2007
Case series: multiple patients required liver transplantation evaluation after using methasterone-containing supplements. Histology showed centrolobular necrosis and cholestasis consistent with severe 17α-alkylated AAS hepatotoxicity.