Methasterone, best known by the product name Superdrol, is an oral anabolic-androgenic steroid. It is a modified form of dihydrotestosterone (DHT): chemically, it is drostanolone with an added 17α-methyl group, which is why it is also called methyldrostanolone. Its synthesis was reported in 1956, but it was never developed into an approved medicine.
It surfaced in the mid-2000s as an ingredient in over-the-counter “dietary supplements” for muscle building. A run of published cases of severe cholestatic liver injury, sometimes with kidney failure, followed. The DEA placed it in Schedule III in 2012. The single most important fact: there are no controlled human trials of methasterone. What is known about its effects in people comes from case reports, case series and doping-control studies.
This page summarizes what regulators, animal studies and the published case literature report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Drug class | 17α-alkylated anabolic-androgenic steroid (DHT derivative) |
| Other names | Methyldrostanolone, methasteron, 2α,17α-dimethyl-DHT |
| Approval | Never approved as a drug; DEA knows of no legitimate medical use |
| Route | Oral (as sold in supplement products) |
| Studied human doses | None; no clinical trials exist |
| Half-life | No published human pharmacokinetic data |
| Aromatizes to estrogen | No aromatizable A-ring; low estrogen-receptor activity in DEA-reviewed assays |
| Main documented harm | Cholestatic liver injury, often with kidney injury (case reports) |
| US status | Schedule III anabolic steroid since August 29, 2012 |
| WADA status | Prohibited at all times (S1.1 anabolic androgenic steroids) |
What it is
Methasterone’s chemical name is 2α,17α-dimethyl-5α-androstan-17β-ol-3-one. Its formula is C₂₁H₃₄O₂ and its molecular weight is 318.5 g/mol (PubChem). The DEA describes it as testosterone with three changes (DEA final rule, 2012):
| Change vs testosterone | What it does |
|---|---|
| No C4–C5 double bond (5α-reduced, like DHT) | Makes it a DHT-type steroid. It lacks the A-ring structure needed for conversion to estrogen. |
| 2α-methyl group | The same group that turns DHT into drostanolone. Reported to impair aromatization and increase anabolic activity. |
| 17α-methyl group | Slows breakdown in the liver so the drug works by mouth. This group is the one linked to cholestatic liver injury across oral steroids. |
Its closest relative in this library is drostanolone, sold as the injectable Masteron. Methasterone is essentially an oral, 17α-methylated drostanolone. The library also covers dymethazine, a two-molecule (azine-linked) form of methasterone, and the closely related methylstenbolone (Tran et al., Steroids 2023).
In receptor assays commissioned by the DEA, methasterone bound the androgen receptor about as well as testosterone and activated it somewhat more strongly. It showed low binding and little or no activation at estrogen, progesterone and glucocorticoid receptors. An older mouse study reported anti-estrogenic activity (DEA final rule, 2012).
About the “400:20” anabolic:androgenic claim. Online sources often describe Superdrol as having 400% of the anabolic and 20% of the androgenic effect of methyltestosterone. That traces back to a 1960 study in rats given the drug by mouth, as summarized by the DEA. It is an animal assay, not a human measurement. Later DEA-commissioned studies in castrated rats found methasterone prevented atrophy of the prostate, seminal vesicles and levator ani muscle to a degree comparable with testosterone and methyltestosterone. In other words, it is clearly androgenic as well as anabolic.
How it works in the body
No study has measured methasterone blood levels or half-life in humans, so any half-life figure quoted online is unsupported. What is known comes from metabolism studies used in anti-doping work:
- Human liver cells. In cultured human hepatocytes, the main metabolites were 3α-reduced forms, with smaller amounts of 3β-reduced and hydroxylated products. The same metabolites appeared in urine after a human volunteer took the drug (Gauthier et al., Steroids 2009).
- Urinary detection. In one healthy male volunteer, 15 urinary metabolites were found. The longest-lasting, a glucuronide conjugate, was detectable for up to 10 days after the dose (Zhang et al., Int J Mol Sci 2016).
The detection window is not the same as how long the drug is active. It only says how long traces can be found in urine by sensitive lab methods.
Regulatory status
Methasterone was never submitted for approval as a drug. In its scheduling rule, the DEA said it was not aware of any legitimate medical use or New Drug Application for it, and found no manufacturers using it as a chemical intermediate (DEA final rule, 2012).
Key events in the US:
| Date | Event |
|---|---|
| 1956 | Synthesis reported (Ringold and Rosenkranz) |
| 1959 | Anabolic activity reported in castrated rats |
| March 2006 | FDA Warning Letter over adverse effects linked to the product Superdrol |
| March 2010 | DEA had identified 62 dietary supplements claiming to contain methasterone, sold online |
| November 23, 2011 | DEA proposed classifying methasterone as a Schedule III anabolic steroid |
| August 29, 2012 | Final rule took effect; methasterone and its salts, esters and ethers became Schedule III |
Sources: DEA proposed rule, 2011; DEA final rule, 2012. Methasterone is listed by name in the Schedule III anabolic steroid list (21 CFR 1308.13).
In sport, it is named under S1.1 anabolic androgenic steroids, prohibited both in and out of competition (WADA 2026 Prohibited List).
What the research shows
No human efficacy data
There are no randomized or controlled human trials of methasterone for muscle mass, strength or any medical condition. Claims about how much muscle or strength it builds come from marketing and user reports, not from studies. The only controlled data on its anabolic effect are rat assays, described above.
Liver injury case reports
Almost all of the human literature on methasterone describes harm. The pattern is consistent: severe cholestasis (blocked bile flow, causing jaundice and intense itching), often appearing or worsening after the product is stopped.
| Report | Patients | Main findings |
|---|---|---|
| Jasiurkowski et al., Am J Gastroenterol 2006 | 1 | Cholestatic jaundice and IgA nephropathy (a kidney inflammation) after Superdrol, a product advertised as having no hormonal activity |
| Shah et al., Clin Gastroenterol Hepatol 2008 | 5 | Previously healthy users developed jaundice about 2 weeks after stopping; bilirubin peaked 2–3 weeks after presentation; all resolved about 12 weeks after presentation |
| Nasr and Ahmad, Dig Dis Sci 2009 | 1 | Severe cholestasis with renal failure linked to Superdrol |
| Singh et al., J Clin Gastroenterol 2009 | 1 | Severe hepatotoxicity from a methasterone-containing supplement |
| Krishnan et al., J Clin Gastroenterol 2009 | 3 liver, 1 kidney | Prolonged intrahepatic cholestasis and one case of renal failure from steroid-enriched supplements; cited by the DEA among methasterone reports |
| Khurana and Dasanu, Conn Med 2014 | 1 | Transient cholestatic hepatitis followed by severe aplastic anemia (bone marrow failure) in a young man |
Larger case series
Two larger reviews show that methasterone is the steroid most often implicated in supplement-related liver injury:
- US Drug-Induced Liver Injury Network (DILIN). Among 44 men with bodybuilding-supplement liver injury, median time to onset was 73 days. All had jaundice, 84% had itching and 71% were hospitalized; none died or needed a transplant. Products from 14 patients were chemically tested. Methyldrostanolone (methasterone) was the anabolic steroid found most often, and 17 of 21 steroid-containing products held steroids different from those on the label (Stolz et al., Aliment Pharmacol Ther 2019).
- UK review of 52 cases. Methyldrostanolone was the most common steroid taken. Patients presented a median of 56 days after starting, and bilirubin peaked a median of 28 days after stopping. Biopsies showed “bland” cholestasis, 43% developed kidney injury, and none died or needed a transplant (Abeles et al., BMJ Open Gastroenterol 2020).
These are case series, not trials, so they cannot give an injury rate. They show what kind of harm occurs and how it unfolds, not how often.
Side effects and risks
Liver
Cholestatic liver injury is the best-documented risk. Typical features from the reports above:
- jaundice and itching, sometimes with fatigue, nausea or weight loss;
- very high bilirubin with only modest rises in liver enzymes;
- a delayed course, with bilirubin continuing to rise for weeks after stopping;
- slow recovery over roughly three months in the reported cases.
Kidneys
Kidney injury occurs alongside the liver injury in a substantial share of reported cases: 43% in the UK review (Abeles et al., 2020). The DILIN authors noted that methasterone in particular had been linked to kidney injury in earlier reports (Stolz et al., 2019).
Hormonal and other class effects
No study has measured methasterone’s effects on testosterone, LH, FSH, sperm or cholesterol in people. As a potent androgen-receptor agonist, it would be expected to share the class effects that the DEA lists for anabolic steroids: testicular atrophy and reduced sperm count in men; voice deepening, body hair growth and clitoral enlargement in women, which can be permanent; and adverse cholesterol changes (DEA final rule, 2012). These are class-level expectations, not methasterone-specific measurements.
Quality and contamination
Methasterone is a recurring hidden ingredient in supplements:
- Mislabeled products. In the DILIN analysis, most steroid-containing products held steroids not listed on the label (Stolz et al., 2019). The UK cases of a product called Mass-Drol involved a steroid listed under one of methasterone’s alternative chemical names (El Sherrif et al., Liver Int 2013).
- Contaminated vitamins. In New York in 2012–2013, about 16 people reported symptoms such as fatigue, scalp hair loss and muscle aches after taking B-50 vitamin and multimineral supplements from one supplier. Lab tests found significant levels of methasterone, dymethazine and methylstenbolone. One patient was hospitalized for liver damage, and a child showed severe virilization (Tran et al., Steroids 2023).
Key takeaways
- A designer oral steroid, never a medicine. Methasterone is 17α-methylated drostanolone. It was synthesized in 1956 but never approved, and was later sold as a “supplement.”
- No human trials. Its anabolic reputation rests on rat assays and marketing. No controlled study has tested it in people, and its human half-life is unknown.
- The famous ratio is from rats. The “400:20” figure comes from a 1960 rat study. Later rat studies found androgenic effects comparable to testosterone.
- Cholestatic liver injury is the signature harm. Case series show severe jaundice that can worsen for weeks after stopping, often with kidney injury.
- Controlled and banned. It has been a US Schedule III anabolic steroid since 2012 and is prohibited at all times under WADA rules.
- It turns up in mislabeled products. It has been found in supplements that did not list it, including vitamin products.
Sources
- Drug Enforcement Administration. Classification of two steroids, prostanozol and methasterone, as Schedule III anabolic steroids under the Controlled Substances Act. Final rule. Federal Register. July 30, 2012;77(146):44456–44462 (FR Doc 2012-18495). govinfo.
- Drug Enforcement Administration. Classification of two steroids, prostanozol and methasterone, as Schedule III anabolic steroids under the Controlled Substances Act. Notice of proposed rulemaking. Federal Register. November 23, 2011;76:72355 (FR Doc 2011-30081). govinfo.
- 21 CFR 1308.13. Schedule III. eCFR.
- World Anti-Doping Agency. The 2026 Prohibited List. In effect January 1, 2026. WADA 2026 Prohibited List.
- National Center for Biotechnology Information. PubChem Compound Summary for CID 237186, Methasterone. PubChem.
- Gauthier J, Goudreault D, Poirier D, Ayotte C. Identification of drostanolone and 17-methyldrostanolone metabolites produced by cryopreserved human hepatocytes. Steroids. 2009;74(3):306–314. PubMed.
- Zhang J, Lu J, Wu Y, et al. New potential biomarker for methasterone misuse in human urine by liquid chromatography quadrupole time of flight mass spectrometry. Int J Mol Sci. 2016;17(10):1628. PubMed.
- Jasiurkowski B, Raj J, Wisinger D, et al. Cholestatic jaundice and IgA nephropathy induced by OTC muscle building agent superdrol. Am J Gastroenterol. 2006;101(11):2659–2662. PubMed.
- Shah NL, Zacharias I, Khettry U, et al. Methasteron-associated cholestatic liver injury: clinicopathologic findings in 5 cases. Clin Gastroenterol Hepatol. 2008;6(2):255–258. PubMed.
- Nasr J, Ahmad J. Severe cholestasis and renal failure associated with the use of the designer steroid Superdrol (methasteron): a case report and literature review. Dig Dis Sci. 2009;54(5):1144–1146. PubMed.
- Singh V, Rudraraju M, Carey EJ, et al. Severe hepatotoxicity caused by a methasteron-containing performance-enhancing supplement. J Clin Gastroenterol. 2009;43(3):287. PubMed.
- Krishnan PV, Feng ZZ, Gordon SC. Prolonged intrahepatic cholestasis and renal failure secondary to anabolic androgenic steroid-enriched dietary supplements. J Clin Gastroenterol. 2009;43(7):672–675. PubMed.
- Khurana A, Dasanu CA. Hepatitis associated aplastic anemia: case report and discussion. Conn Med. 2014;78(8):493–495. PubMed.
- Stolz A, Navarro V, Hayashi PH, et al. Severe and protracted cholestasis in 44 young men taking bodybuilding supplements: assessment of genetic, clinical and chemical risk factors. Aliment Pharmacol Ther. 2019;49(9):1195–1204. PubMed.
- Abeles RD, Foxton M, Khan S, et al. Androgenic anabolic steroid-induced liver injury: two case reports assessed for causality by the updated Roussel Uclaf Causality Assessment Method (RUCAM) score and a comprehensive review of the literature. BMJ Open Gastroenterol. 2020;7(1):e000549. PubMed.
- El Sherrif Y, Potts JR, Howard MR, et al. Hepatotoxicity from anabolic androgenic steroids marketed as dietary supplements: contribution from ATP8B1/ABCB11 mutations? Liver Int. 2013;33(8):1266–1270. PubMed.
- Tran BN, Okoniewski R, Spink BC, et al. Androgenic steroids in over-the-counter dietary supplements: analysis for association with adverse health effects. Steroids. 2023;193:109199. PubMed.