Oxymetholone (Anadrol)

Oxymetholone, sold as Anadrol-50 (and once known as Anapolon), is a synthetic anabolic-androgenic steroid (a lab-made hormone that builds muscle and acts like testosterone), usually shortened to AAS. You take it as a pill, and it comes from dihydrotestosterone, a natural form of testosterone. To be clear up front: it is a steroid — not a peptide, and not a SARM. It does have a real, FDA-approved medical use for certain types of anemia, and there are solid clinical trials behind its use in wasting illness. But it is also one of the harsher oral steroids on the body, with serious, well-documented effects on the liver, blood fats, and hormones.

What it is

The full chemical name is 2-hydroxymethylene-17α-methyl-dihydrotestosterone — a tweaked version of dihydrotestosterone (DHT), a natural androgen. Chemists added a small methyl group at a spot called C17 (a change known as 17α-alkylation). That tweak lets the drug survive its first trip through the liver, so it works when swallowed — which is why Anadrol is a tablet rather than a shot. The catch: that same chemical tweak is exactly what makes 17α-alkylated oral steroids hard on the liver.

Here is how it works in the body. Like other anabolic steroids, it switches on the androgen receptor (the cellular “docking station” for testosterone-like hormones), which is found inside cells. Flipping that switch drives the anabolic effects (building protein and muscle, and helping the body hold on to nitrogen, a building block of muscle) along with the androgenic effects (the testosterone-like, masculinizing ones). Because it is a DHT relative, the body cannot convert it into estrogen — that conversion is done by an enzyme called aromatase, and this drug is not a target for it. Even so, oxymetholone is known for causing estrogen-type side effects anyway, such as breast tissue growth in men and fluid buildup. Doctors see this clearly but don’t fully understand why; the leading guess is that the drug itself has some built-in estrogen-like or progesterone-like activity. Its benefit for anemia comes from boosting the making of red blood cells. The FDA label says it increases both the production and the urinary output of erythropoietin (the hormone that tells the body to make red blood cells) in people whose bone marrow is failing.

The claims

The one use the FDA has approved is treating anemias where the body isn’t making enough red blood cells — including acquired aplastic anemia, congenital aplastic anemia, myelofibrosis, and the low-blood-cell states caused by drugs that damage bone marrow. Beyond that approved use, researchers have also tested it for wasting (severe weight and muscle loss) in people with HIV, and for blood-sugar handling and muscle loss in people on long-term dialysis.

In bodybuilding and sports (which is non-medical and against the law without a prescription), oxymetholone is sold as a way to pack on body weight, lean mass, and strength quickly, and as a “kickstart” at the front of a cycle. None of that is approved use, it’s illegal without a prescription, and in competitive sport it counts as doping.

What the evidence actually shows

The strongest human evidence comes from people who were sick and losing weight — not from healthy athletes.

For HIV-associated wasting, Hengge et al. (2003) ran a high-quality trial — double-blind, randomized, and placebo-controlled (meaning patients were randomly assigned, and neither they nor the researchers knew who got the real drug versus a dummy pill). It was a phase III trial in men and women with normal hormone levels (n=89, 16 weeks). Oxymetholone produced real, statistically significant weight gain (3.0 ± 0.5 kg and 3.5 ± 0.7 kg in the two treatment groups versus 1.0 ± 0.7 kg with placebo) and increased body cell mass (the body’s active, working tissue), and people reported better appetite and well-being (PMID 12646793, AIDS 2003;17(5):699–710; a separate full write-up of the same trial appears in HIV Clinical Trials 2003;4(3):150–163, PMID 12815555). The big downside was liver trouble: liver-enzyme readings (transaminase or GGT — blood markers that rise when the liver is stressed) jumped to more than 5× the starting level in 43% of one treatment group and 25% of the other, versus 8% on placebo. An earlier, smaller pilot study without blinding (Hengge et al. 1996, n=30 treated vs matched controls, 30 weeks) found the drug safe and helpful for weight gain in advanced HIV-1 infection (PMID 8785183, Br J Nutr 1996;75(1):129–138).

For people on long-term dialysis, Aramwit, Kobpipat, Satirapoj, Kopple, and Supasyndh (2009) ran a randomized controlled trial (RCT — patients randomly assigned to drug or placebo) (n=44, 24 weeks). Oxymetholone improved how well the body responded to insulin (a lower HOMA index, a measure of insulin handling), added fat-free/lean mass, and trimmed fat mass compared with placebo — but, again, liver enzymes rose in the treated patients (PMID 19356374, Clin Nephrol).

For muscle and strength in healthy athletes, the evidence is thin and weaker. The solid, controlled proof of effect comes from sick, weight-losing groups rather than from careful trials in healthy athletes; across the studies, the steady finding is that people gain body weight and lean/active tissue, while also picking up liver and blood-fat problems. A review-style paper (Pavlatos, Fultz, Monberg, Vootkur 2001, Clin Ther 23(6):789–801, PMID 11440282) walks through the FDA-approved anemia use and the experimental uses, set against its liver risks.

So the evidence that oxymetholone reliably adds weight and lean mass in humans is strong — but it’s strongest in sick, weight-losing patients, and it always seems to come packaged with a liver-toxicity warning sign.

Legal and regulatory status

In the United States, anabolic steroids are Schedule III controlled substances under the Controlled Substances Act. They were placed there by the Anabolic Steroids Control Act of 1990 (Pub. L. 101-647; effective Feb 27, 1991) and the list was widened by the Anabolic Steroid Control Act of 2004 (Pub. L. 108-358), which broadened the legal definition at 21 U.S.C. 802(41). Oxymetholone is specifically named among those steroids and sits at Schedule III. Having it, handing it out, or using it for non-medical reasons without a prescription is illegal. (For comparison: clenbuterol is not FDA-approved for people and is not a scheduled controlled substance, and human growth hormone is handled separately under 21 U.S.C. 333(e) rather than through CSA scheduling.)

In sport, oxymetholone is on the WADA Prohibited List under S1 (Anabolic Agents), subcategory S1.1 (Anabolic Androgenic Steroids), and is banned at all times — both in and out of competition — on the 2026 Prohibited List effective January 1, 2026. By contrast, clenbuterol and SARMs land under S1.2 (“Other Anabolic Agents”), and HGH and hCG fall under S2 (peptide hormones and related substances). Oxymetholone is a true steroid, so it sits under S1.1.

Safety

Having a medical track record does not make oxymetholone a gentle drug. It carries the full, serious risk profile of a strong 17α-alkylated oral androgen.

• Liver damage (the big one, and typical of 17α-alkylated pills): liver-enzyme spikes that get worse with higher doses and longer use; cholestatic jaundice (a backup of bile that yellows the skin and eyes); peliosis hepatis (where parts of the liver and spleen turn into blood-filled cysts, which can be life-threatening); and liver tumors (usually benign and androgen-driven, but deadly cancerous ones have been reported). The FDA label specifically warns about peliosis hepatis and liver tumors with long-term use, and tells doctors to check liver function regularly and stop the drug if the liver starts failing.
• Heart and cholesterol: sharp, unfavorable shifts in blood fats — HDL (“good”) cholesterol drops and LDL sometimes rises — a known effect of oral 17α-alkylated steroids that the FDA label links to a higher risk of clogged arteries (atherosclerosis). Holding on to fluid and salt can also worsen swelling (edema), high blood pressure, and heart failure.
• Hormone shutdown and fertility: it suppresses the hypothalamic-pituitary-testicular axis (the body’s chain of command for making testosterone), lowering your own testosterone and causing shrunken testicles, reduced sperm production, and infertility — and that shutdown can linger even after you stop the drug.
• Estrogen-type effects: even though it’s a DHT relative that can’t turn into estrogen, oxymetholone is well known for causing breast tissue growth in men (gynecomastia) and fluid retention.
• Masculinizing effects (especially in women and children): extra body/facial hair, a deepening voice (which may not reverse), clitoral enlargement, and irregular periods; in children, it can fuse the growth plates early and speed up bone aging, which can stunt growth.
• Blood: the intended red-blood-cell boost can overshoot into too many red cells (polycythemia) or a high hematocrit (the share of blood made up of red cells), which raises the risk of clots.
• Other: acne, oily skin, male-pattern hair loss, mood and aggression changes, and possible prostate effects in older men. It must not be used in pregnancy (it harms the fetus and masculinizes it), in prostate or male breast cancer, or in serious liver problems.

Bottom line

Oxymetholone is a real, FDA-approved anabolic-androgenic steroid with genuine, trial-backed proof that it adds weight and lean mass — but that proof comes from wasting and catabolic illness (HIV wasting, dialysis), not from healthy recreational users, and it always rides along with a clear, serious liver-toxicity warning. It’s a Schedule III prescription steroid, banned at all times in sport (WADA S1.1), and one of the harder oral steroids on the body, with documented risks to the liver, blood fats, hormones, and (in women and children) masculinizing changes that may not reverse. It is a steroid, not a peptide.

Evidence grade: 9/10 · Strong.

Sources

• Anadrol-50 (oxymetholone) FDA prescribing information — RxList
• Anadrol-50 (oxymetholone) label via DailyMed
• Pavlatos AM et al. 2001 — Review of oxymetholone, a 17α-alkylated AAS (Clin Ther; PMID 11440282)
• Hengge UR et al. 1996 — oxymetholone promotes weight gain in advanced HIV-1 infection (Br J Nutr; PMID 8785183)
• Hengge UR et al. 2003 — double-blind, randomized, placebo-controlled phase III trial of oxymetholone for HIV wasting (AIDS; PMID 12646793)
• Hengge UR et al. 2003 — oxymetholone for HIV-wasting, phase III trial in eugonadal men and women (HIV Clin Trials; PMID 12815555)
• Aramwit P et al. 2009 — oxymetholone ameliorates insulin sensitivity in maintenance hemodialysis patients, RCT (Clin Nephrol; PMID 19356374)
• NIH LiverTox — Androgenic Steroids (hepatotoxicity of 17α-alkylated AAS)
• WADA Prohibited List (oxymetholone under S1.1 Anabolic Androgenic Steroids; prohibited at all times)
• Anabolic Steroid Control Act of 2004, Pub. L. 108-358
• 21 U.S.C. 802 — definition of anabolic steroid (§802(41))
• 21 U.S.C. 333 — penalties (HGH at §333(e))
• Anabolic Steroids Control Act of 1990 (H.R. 4658, 101st Congress)
• Federal Register — Implementation of the Anabolic Steroid Control Act of 2004