The verdict
Our read at a glance.
Whether anything sold as a supplement but structurally an anabolic steroid can be assessed as a supplement.
- The signal
- There is no legitimate efficacy literature because it was never developed as a medicine. What exists is toxicology and forensics: a published case of severe cholestasis and renal failure associated with use of the designer steroid Superdrol, metabolism studies conducted specifically to enable doping detection, and repeated analytical surveys finding androgenic steroids in over-the-counter dietary supplements. That is the entire record.
- The unknown
- How much undetected liver and kidney injury occurred during the years it was sold openly, since users had no reason to associate a supplement with hepatic failure.
- Our read
- The case study for why supplement is a legal category and not a safety category. A 17-alpha-alkylated anabolic steroid sold next to protein powder, with hospital case reports as its clinical literature. If a product produces steroid-like results, the correct default assumption is that it contains one.
The mechanism
How it works.
Methasterone is drostanolone with an added 17-alpha methyl group - a dihydrotestosterone-derived androgen made orally active by exactly the modification that causes hepatic injury. Because it descends from dihydrotestosterone it cannot be aromatised, so it produces no oestradiol, which removes the oestrogenic side effects and also removes oestrogen's protective contribution to lipids and endothelial function. The combination of high androgen receptor potency, 17-alpha alkylation and no aromatisation is the reason its harm profile skews so hard toward the liver and toward HDL suppression rather than toward the water retention and gynaecomastia associated with older orals.
Safety & regulatory boundary
The consequential part.
Not an approved drug and never was. Now a Schedule III controlled substance in the United States following designer-steroid control legislation, and unlawful as a dietary supplement ingredient. Published case reports document cholestatic liver injury with renal involvement. It is 17-alpha-alkylated and non-aromatising, with the severe HDL suppression that combination predicts. Prohibited in sport.
What's next
What we're watching.
Continued analytical surveillance of over-the-counter products, which is where this class keeps reappearing under new names.
Context
Why this is discussed.
It built a reputation for extreme strength gain per milligram, and because it was sold on shelves rather than through the black market, a lot of people took it believing it was a legal prohormone.
The evidence base
12 cited references.
Indexed literature (PubMed)12
Geldof L et al. · Biomed Chromatogr · 2016
Tran BN et al. · Steroids · 2023
Aamer M et al. · RSC Adv · 2022
Khurshid S et al. · Steroids · 2025
Kędzierski J et al. · Toxicol Lett · 2023
Geldof L et al. · Biomed Chromatogr · 2014
Lootens L et al. · J Steroid Biochem Mol Biol · 2011
Geyer H et al. · J Mass Spectrom · 2008
Nasr J et al. · Dig Dis Sci · 2009
Weththasinghe SA et al. · Drug Test Anal · 2018
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