Superdrol or Oxymetholone: What Is the Difference

Superdrol (methasterone) and oxymetholone (Anadrol) are both oral 17α-methylated derivatives of dihydrotestosterone, and they are often put in the same row. However, the history, evidence base, and regulatory status of these substances are radically different: oxymetholone is a registered medicine with an FDA label, while superdrol is a "designer" steroid that reached the market under the guise of a dietary supplement. The editorial team examines what the difference is.

Origin: a medicine against anemia and a "designer" steroid

Oxymetholone was synthesized in the 1950s, and in the United States it still has an official label under the name Anadrol-50. Its main indication is anemias caused by insufficient production of red blood cells: aplastic anemia, myelofibrosis, hypoplastic anemias. Before the advent of recombinant erythropoietin, androgens were one of the few ways to stimulate blood formation.

Methasterone was described in the scientific literature back in the 1950s, but it was never registered as a medicine. In the early 2000s it appeared on the US market under the name Superdrol as an alleged "prohormone" in sports supplements, exploiting gaps in legislation.

Subsequently, methasterone was classified as a controlled substance in the United States (the 2014 Designer Anabolic Steroid Control Act fixed it in the list), and the FDA has repeatedly warned about products containing steroids disguised as supplements.

Thus, the first key difference: for oxymetholone there are controlled clinical trials and a label with warnings, whereas for superdrol the main information about effects on humans comes from clinical cases of liver injury.

Chemical structure of two methylated DHTs

Both molecules are built on the 5α-androstane (DHT) skeleton and have a methyl group at position 17α, which provides oral activity. The difference is in ring A.

Methasterone is effectively a 17α-methylated version of drostanolone (masteron). This means that oral activity and the liver burden typical of 17α-alkylated steroids are added to the properties of drostanolone.

Oxymetholone has a hydroxymethylene group at position 2, which makes it chemically closer to other 2-substituted DHT derivatives. As a DHT derivative, it is not a substrate of aromatase in the classic sense.

A common feature of both is the 17α-methyl. It is precisely this group that, according to reviews and the LiverTox database, is associated with the cholestatic liver injury characteristic of oral anabolic steroids.

Pharmacology and mechanism of action

Both substances act through the androgen receptor, stimulating protein synthesis in muscles. However, at the systems level they have their peculiarities. Oxymetholone is known for its pronounced stimulation of erythropoiesis, on which its medical use is built.

A paradox has long been discussed in the literature regarding oxymetholone: despite the impossibility of aromatization, some users are described as having estrogen-like effects, in particular gynecomastia and fluid retention. A likely explanation is direct interaction with estrogen receptors or other mechanisms, but this has not been definitively clarified.

Methasterone, as a drostanolone derivative, usually has no estrogenic effects. Its pharmacology in humans has not been systematically studied; existing notions are based on data about structurally similar compounds and on observations.

• In common:androgen receptor agonists, oral activity, suppression of LH/FSH, negative effect on lipids.
• Peculiarity of oxymetholone:pronounced stimulation of blood formation, possible estrogen-like effects.
• Peculiarity of methasterone:absence of clinical trials, data mainly from clinical cases.

Both substances suppress the "hypothalamus-pituitary-testes" axis, so their use is accompanied by a decrease in one's own testosterone and spermatogenesis, which can persist for a long time after discontinuation.

Clinical data and regulatory status

For oxymetholone there are randomized trials, in particular in patients with HIV-associated wasting. In a placebo-controlled study by Hengge and colleagues (2003), oxymetholone promoted weight gain, but some participants had a significant increase in liver enzymes.

The Anadrol-50 label contains warnings about peliosis hepatis, liver tumors, and changes in the lipid profile, as well as about the need for regular monitoring of liver function. These risks are described precisely for medical use under supervision.

For methasterone there are no controlled studies in humans. Instead, a number of clinical cases of severe cholestasis have been published, in particular a report by Nasr and Ahmad (2009) about severe cholestasis and kidney failure associated with taking Superdrol.

Both substances are included in section S1 of the WADA Prohibited List. Oxymetholone is available legally only by prescription in countries where it is registered; methasterone has no legal medical circulation.

The liver and other risks

The main common risk is drug-induced liver injury. The Spanish hepatotoxicity registry (Robles-Diaz et al., 2015) described a distinct phenotype of injury associated with illegal AAS: pronounced cholestasis with jaundice and prolonged recovery. Among the causative products, "supplements" containing methylated steroids often appeared.

Other risks are typical for AAS: decreased HDL, increased LDL, possible increase in blood pressure, erythrocytosis. For oxymetholone, an increase in hematocrit is especially expected given its main pharmacological action.

For women, both substances carry a risk of virilization. For men, suppression of spermatogenesis and a risk of prolonged hypogonadism.

A separate factor is the composition of products. Goods under the names "superdrol" or "methasterone" are often sold as supplements, and their actual composition may differ from what is stated, which further complicates risk assessment.

Editorial conclusions

Oxymetholone and superdrol are chemically related - both are 17α-methylated derivatives of DHT - but they belong to different worlds: the first has a label, indications, and clinical trials, while the second appeared on the market as a "supplement" and is known to science mainly from reports of liver injury.

Common to them are hepatotoxicity, a negative effect on lipids, suppression of the hormonal system, and a WADA ban.

If you see on the label of a sports supplement names like "methasterone" or "2α,17α-dimethyl," this is a signal that the product contains an anabolic steroid.

The editorial team also recommends reading "Superdrol vs Oxymetholone: what to choose and for whom," a review of liver tests, and an article about hidden steroids in supplements.

References

1. Anadrol-50 (oxymetholone) tablets. Prescribing information. U.S. Food and Drug Administration.
2. Hengge UR, Stocks K, Faulkner S, et al. Oxymetholone for the treatment of HIV-wasting: a double-blind, randomized, placebo-controlled phase III trial in eugonadal men and women. HIV Clin Trials. 2003;4(3):150–163.
3. 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.
4. Robles-Diaz M, Gonzalez-Jimenez A, Medina-Caliz I, et al. Distinct phenotype of hepatotoxicity associated with illicit use of anabolic androgenic steroids. Aliment Pharmacol Ther. 2015;41(1):116–125.
5. LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. Androgenic Steroids. Bethesda (MD): National Institute of Diabetes and Digestive and Kidney Diseases.
6. Kicman AT. Pharmacology of anabolic steroids. Br J Pharmacol. 2008;154(3):502–521.
7. World Anti-Doping Agency. International Standard: Prohibited List. Montreal: WADA; 2025.