Oxymetholone, sold in the US as Anadrol-50, is an oral anabolic-androgenic steroid built on the dihydrotestosterone (DHT) skeleton. Its only FDA-approved use is the treatment of anemias caused by deficient red blood cell production, such as aplastic anemia and myelofibrosis. It was later studied for HIV wasting, muscle loss in older men and anemia in kidney failure.
The single most important fact is its liver risk. The label carries a boxed warning for peliosis hepatis (blood-filled cysts in the liver), liver tumors and harmful lipid changes. In trials of 100–150 mg/day, a quarter to a third of patients had large liver enzyme rises. Drugs@FDA now lists the only US product, Anadrol-50, as discontinued.
This page summarizes what the FDA label, clinical trials and regulators report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Drug class | 17α-alkylated anabolic-androgenic steroid (DHT derivative) |
| Brand / application | Anadrol-50, NDA 016848; listed as discontinued in Drugs@FDA |
| Route | Oral tablet |
| Strength | 50 mg scored tablet |
| Labeled dose | 1–5 mg/kg/day; usual effective dose 1–2 mg/kg/day |
| Approved indication | Anemias caused by deficient red cell production |
| Half-life | Not stated on the label; no verified human elimination half-life (time to peak ≈ 3.5 h after 50 mg) |
| Boxed warning | Peliosis hepatis, liver cell tumors, blood lipid changes |
| US status | Schedule III controlled substance |
| WADA status | Prohibited at all times (S1.1 anabolic androgenic steroids) |
What it is
Oxymetholone’s chemical name is 17β-hydroxy-2-(hydroxymethylene)-17-methyl-5α-androstan-3-one (FDA label). Its formula is C₂₁H₃₂O₃ and its molecular weight is 332.5 g/mol (PubChem). It differs from DHT in two ways:
| Change | What it does |
|---|---|
| 2-hydroxymethylene group | Adds a hydroxymethylene side group at carbon 2 of the A-ring, the main structural difference from 17α-methylated DHT |
| 17α-methyl group | Slows breakdown in the liver so the drug survives oral dosing. The label ties this group to cholestatic hepatitis and jaundice “at relatively low doses.” |
The label describes oxymetholone as “a potent anabolic and androgenic drug.” It adds that oxymetholone raises the production and urinary excretion of erythropoietin (the kidney hormone that drives red cell production) in patients with bone marrow failure. Like other anabolic steroids, it suppresses the pituitary’s gonadotropins (LH and FSH).
About anabolic:androgenic ratios. Online sources often quote a ratio for oxymetholone. We could not trace it to an original assay, so we do not repeat it. The FDA label states that “complete dissociation of anabolic and androgenic effects has not been achieved.”
Pharmacokinetics
Oxymetholone was approved before modern pharmacokinetic studies were required. A 2001 review noted that few pharmacokinetic studies were done before its approval in the 1960s (Pavlatos et al., Clin Ther 2001). The label gives no half-life.
The one human plasma study we could find gave healthy volunteers a single 50 mg oral dose (Cardoso et al., J Chromatogr B 2002):
| Parameter | Value |
|---|---|
| Peak plasma concentration (Cmax) | 18.8 ± 0.4 ng/mL |
| Time to peak (Tmax) | 210 ± 42 min (≈ 3.5 h) |
| Elimination half-life | Not reported in the abstract |
Half-life figures that circulate online do not appear in the label or in this study, and we could not verify any of them.
Approved medical use
The label approves Anadrol-50 for anemias caused by deficient red cell production. It names the following as often responding:
- acquired aplastic anemia;
- congenital aplastic anemia;
- myelofibrosis;
- hypoplastic anemias caused by myelotoxic (bone-marrow-damaging) drugs.
It should not replace transfusion, correction of iron, folate, B12 or pyridoxine deficiency, antibiotics, or corticosteroids where these are appropriate.
| Labeled dosing point | Detail |
|---|---|
| Dose range, children and adults | 1–5 mg/kg/day |
| Usual effective dose | 1–2 mg/kg/day, individualized |
| Minimum trial | 3–6 months, because response is often slow |
| After remission | Some patients stop; others continue at a lower dose. Congenital aplastic anemia usually needs ongoing maintenance. |
Drugs@FDA records the original approval of NDA 016848 on January 18, 1972, and the current marketing status as discontinued (Drugs@FDA). Today, transplant and immunosuppression are first-line in severe aplastic anemia. Androgens are reserved for patients who are not eligible for those options (Pengthina and Saelue, J Blood Med 2022).
What the research shows
Aplastic anemia and other marrow failure
The strongest controlled evidence is a European randomized trial in 134 patients with acquired aplastic anemia (Bacigalupo et al., Br J Haematol 1993). All received antilymphocyte globulin and methylprednisolone; half were randomized to add oxymetholone 2 mg/kg/day for 4 months.
| Outcome | With oxymetholone (n = 69) | Without (n = 65) |
|---|---|---|
| Response at 120 days | 56% | 40% (p = 0.04) |
| Response, patients alive at 120 days | 68% | 48% (p = 0.02) |
| Response, women with neutrophils below 0.5 × 10⁹/L | 78% | 27% (p = 0.03) |
| Early mortality (first 120 days) | 17% | 17% |
| Survival | 71% | 65% (not significant) |
Oxymetholone improved response rates but not survival. Side effects, including liver test changes and virilization, were reported as controllable and reversible.
More recent data are observational:
- Adults in Thailand, oxymetholone alone. A cohort of 110 patients had an overall response of 56.4% at 6 months, with a median time to transfusion independence of 11.8 weeks. 17.9% stopped for side effects, mostly hepatitis; androgenic side effects occurred in 55.5% (Chaipokam and Rojnuckarin, Ann Hematol 2025).
- Severity matters. In a matched analysis of 74 patients, 1-year response was 54.1% in nonsevere disease but 13.5% in severe or very severe disease (Pengthina and Saelue, J Blood Med 2022).
- Inherited marrow failure. In a Canadian registry of 29 children treated with oxymetholone or danazol, 55% had a hematologic response. Danazol had a better toxicity profile with similar efficacy (Català et al., Br J Haematol 2020).
HIV-associated wasting
A double-blind trial randomized 89 HIV-positive men and women with wasting to oxymetholone 50 mg two or three times daily, or placebo, for 16 weeks (Hengge et al., AIDS 2003):
| Arm | Weight gain | Body cell mass gain | ALT over 5× baseline |
|---|---|---|---|
| Placebo | +1.0 kg | — | 0% |
| 100 mg/day (50 mg twice daily) | +3.5 kg | +3.8 kg | 27% |
| 150 mg/day (50 mg three times daily) | +3.0 kg | +2.1 kg | 35% |
Both doses beat placebo for weight. The higher dose added no benefit and caused more liver toxicity. Appetite, food intake and self-rated weakness also improved. An earlier 30-week pilot study, without a placebo group, reported an average peak weight gain of 8.2 kg on oxymetholone alone (Hengge et al., Br J Nutr 1996).
Older men
A placebo-controlled trial randomized 31 men aged 65–80 to placebo, 50 mg/day or 100 mg/day for 12 weeks (Schroeder et al., Am J Physiol Endocrinol Metab 2003):
| Measure | Placebo | 50 mg/day | 100 mg/day |
|---|---|---|---|
| Lean body mass | 0.0 kg | +3.3 kg | +4.2 kg |
| Trunk fat | −0.2 kg | −1.7 kg | −2.2 kg |
| Chest press 1RM | −0.8% | +8.2% | +13.9% |
| Lat pull-down 1RM | −0.6% | +8.8% | +18.4% |
| HDL cholesterol | — | −19 mg/dL | −23 mg/dL |
| ALT | — | — | +72 U/L |
Gains in lean mass and upper-body strength appeared to rise with dose. So did the drop in HDL (“good”) cholesterol, and the 100 mg dose raised the liver enzyme ALT significantly.
Kidney failure
In two small Thai randomized trials, oxymetholone 50 mg twice daily was given to people on dialysis:
- Hemodialysis, 44 patients, 24 weeks. Fat-free mass rose 3.24 kg vs 0.65 kg on placebo, and insulin resistance improved. Liver enzymes rose in 2 of 21 treated patients (Aramwit et al., Clin Nephrol 2009).
- Peritoneal dialysis with erythropoietin, 24 patients, 6 months. Hematocrit reached 38.1% vs 32.8% on placebo, and hemoglobin 12.9 vs 11.0 g/dL. Rising liver enzymes were the main side effect (Aramwit et al., Int J Clin Pharmacol Ther 2010).
Side effects and risks
Boxed warning: peliosis hepatis, liver tumors and lipids
The label’s boxed warning covers three class risks of anabolic steroids:
- Peliosis hepatis. Liver, and sometimes spleen, tissue is replaced by blood-filled cysts. It can go unnoticed until liver failure or bleeding into the abdomen. Stopping the drug usually clears the lesions.
- Liver cell tumors. Most are benign and androgen-dependent, but fatal malignant tumors have been reported. These tumors are highly vascular and may be silent until they bleed.
- Blood lipid changes. HDL falls and LDL sometimes rises, which can be marked and raise the risk of atherosclerosis.
A review of published cases found 36 people with Fanconi anemia and 97 without it who developed liver tumors on androgens. Oxymetholone and methyltestosterone were the androgens most often linked to hepatocellular carcinoma (Velazquez and Alter, Am J Hematol 2004). The authors noted that the size of the risk cannot be calculated, because the number of treated patients is unknown.
Liver injury
Beyond the boxed warning, the label warns that 17α-alkylated androgens cause cholestatic hepatitis and jaundice. It is usually reversible, but continued use has been linked to hepatic coma and death. The label recommends periodic liver function tests. Trial data show how common enzyme rises are:
| Setting | Liver finding |
|---|---|
| HIV wasting, 100 mg/day | ALT over 5× baseline in 27% |
| HIV wasting, 150 mg/day | ALT over 5× baseline in 35% |
| Older men, 100 mg/day | ALT rose by a mean 72 U/L |
| Aplastic anemia cohort, most starting at 150 mg/day | 15 of 110 stopped because of hepatitis |
Hormonal and androgenic effects
The label lists the following:
- Men: inhibition of testicular function, testicular atrophy, oligospermia (low sperm count), impotence and gynecomastia.
- Women: virilization, including voice deepening, hirsutism, acne, clitoral enlargement and menstrual changes. Some changes do not reverse even after prompt discontinuation.
- Children: premature closure of the growth plates, which may continue for 6 months after stopping. Bone-age X-rays every 6 months are advised.
Edema and salt retention can occur, and can be serious in people with heart, kidney or liver disease.
Interactions
The label warns of a clinically significant interaction with warfarin. Anabolic steroids can increase sensitivity to oral anticoagulants and prolong clotting times, so the INR (a blood-clotting measure) needs close monitoring and the warfarin dose may need to be lowered. Diabetes medicines may also need adjustment, because anabolic steroids alter glucose tolerance.
Who should not use it
The label contraindicates oxymetholone in:
- men with prostate or breast cancer;
- women with breast cancer and high blood calcium;
- pregnancy (category X);
- nephrosis or the nephrotic phase of nephritis;
- severe liver dysfunction;
- hypersensitivity to the drug.
Monitoring
The label recommends the following checks during treatment:
| What | Why |
|---|---|
| Liver function tests, periodically | 17α-alkylated androgens are hepatotoxic |
| Serum lipids and HDL, periodically | HDL falls and LDL rises |
| Hemoglobin and hematocrit | Polycythemia (too many red cells) at high doses |
| Serum iron and iron-binding capacity | Iron deficiency has been seen on oxymetholone |
| INR or prothrombin time | If taking warfarin |
| Bone-age X-rays every 6 months | Prepubertal patients |
Legal status and use outside medicine
In the US, oxymetholone is listed by name as an anabolic steroid in Schedule III of the Controlled Substances Act (21 CFR 1308.13). In sport, it is named under S1.1 anabolic androgenic steroids on the WADA Prohibited List and is banned at all times (WADA 2026 Prohibited List).
The label states that anabolic steroids “have not been shown to enhance athletic ability.” Products sold outside pharmacies are not regulated for dose, purity or identity. Related oral steroids in this library include Dianabol and Anavar.
Key takeaways
- An anemia drug first. Oxymetholone’s only FDA approval is for anemias from deficient red cell production. In a randomized trial it raised aplastic anemia response rates (56% vs 40%) but not survival.
- Large gains in trials. Older men gained 3.3–4.2 kg of lean mass in 12 weeks on 50–100 mg/day. People with HIV wasting gained about 3–3.5 kg of weight in 16 weeks.
- Higher doses mostly added toxicity. In HIV wasting, 150 mg/day did no better than 100 mg/day but caused more liver enzyme rises.
- The liver is the central risk. The boxed warning covers peliosis hepatis and liver tumors, and 27–35% of HIV trial patients had ALT over 5× baseline.
- Lipids and hormones suffer too. HDL fell by about 19–23 mg/dL in older men, and the label lists testicular suppression and irreversible virilization in women.
- Half-life is not established. The label gives none, and the online figures could not be traced to a source.
Sources
- Unimed Pharmaceuticals. Anadrol-50 (oxymetholone) tablets prescribing information, NDA 016848/S-021, revised August 2004. FDA.
- Food and Drug Administration. Drugs@FDA: NDA 016848, Anadrol-50. FDA.
- National Center for Biotechnology Information. Oxymetholone, PubChem CID 5281034. PubChem.
- Pavlatos AM, Fultz O, Monberg MJ, et al. Review of oxymetholone: a 17alpha-alkylated anabolic-androgenic steroid. Clin Ther. 2001;23(6):789–801. PubMed.
- Cardoso CR, Marques MA, Caminha RC, et al. Validation of the determination of oxymetholone in human plasma analysis using gas chromatography-mass spectrometry. Application to pharmacokinetic studies. J Chromatogr B Analyt Technol Biomed Life Sci. 2002;775(1):1–8. PubMed.
- Bacigalupo A, Chaple M, Hows J, et al. Treatment of aplastic anaemia (AA) with antilymphocyte globulin (ALG) and methylprednisolone (MPred) with or without androgens: a randomized trial from the EBMT SAA working party. Br J Haematol. 1993;83(1):145–151. PubMed.
- Chaipokam J, Rojnuckarin P. Good response to oxymetholone in adult aplastic anemia. Ann Hematol. 2025;104(7):3609–3618. PubMed.
- Pengthina W, Saelue P. Efficacy of oxymetholone in severe and nonsevere acquired aplastic anemia: a propensity score matching analysis. J Blood Med. 2022;13:753–761. PubMed.
- Català A, Ali SS, Cuvelier GDE, et al. Androgen therapy in inherited bone marrow failure syndromes: analysis from the Canadian Inherited Marrow Failure Registry. Br J Haematol. 2020;189(5):976–981. PubMed.
- Hengge UR, Stocks K, Wiehler H, et al. Double-blind, randomized, placebo-controlled phase III trial of oxymetholone for the treatment of HIV wasting. AIDS. 2003;17(5):699–710. PubMed.
- Hengge UR, Baumann M, Maleba R, et al. Oxymetholone promotes weight gain in patients with advanced human immunodeficiency virus (HIV-1) infection. Br J Nutr. 1996;75(1):129–138. PubMed.
- Schroeder ET, Singh A, Bhasin S, et al. Effects of an oral androgen on muscle and metabolism in older, community-dwelling men. Am J Physiol Endocrinol Metab. 2003;284(1):E120–E128. PubMed.
- Aramwit P, Kobpipat N, Satirapoj B, et al. Oxymetholone ameliorates insulin sensitivity in maintenance hemodialysis patients: a randomized controlled trial. Clin Nephrol. 2009;71(4):413–422. PubMed.
- Aramwit P, Palapinyo S, Wiwatniwong S, et al. The efficacy of oxymetholone in combination with erythropoietin on hematologic parameters and muscle mass in CAPD patients. Int J Clin Pharmacol Ther. 2010;48(12):803–813. PubMed.
- Velazquez I, Alter BP. Androgens and liver tumors: Fanconi’s anemia and non-Fanconi’s conditions. Am J Hematol. 2004;77(3):257–267. PubMed.
- Drug Enforcement Administration. Schedules of controlled substances: Schedule III, 21 CFR 1308.13(f). eCFR.
- World Anti-Doping Agency. The 2026 Prohibited List (effective January 1, 2026). WADA.