Anadrol (Oxymetholone): What It Does, What the Evidence Shows, and What the Risks Are

What Exactly Is Anadrol?

Oxymetholone, sold under the brand name Anadrol-50, is a synthetic 17-alpha-alkylated anabolic-androgenic steroid (AAS) derived from dihydrotestosterone (DHT). The FDA approved it in 1972 primarily for the treatment of anemia caused by deficient red-cell production, including aplastic anemia, myelofibrosis, and anemia related to administration of myelotoxic drugs. Because it is 17-alpha-alkylated, it survives first-pass hepatic metabolism well enough to remain orally bioavailable, but that same structural modification is directly responsible for its liver toxicity profile.

The drug works through two mechanisms. First, it binds androgen receptors in skeletal muscle and bone marrow, stimulating erythropoietin production and promoting nitrogen retention. Second, some researchers have proposed a non-receptor-mediated anabolic pathway, though the evidence for that secondary route remains limited to older in-vitro work rather than large controlled trials. The FDA-approved prescribing information lists the approved indication squarely as anemia, and the label has not changed to include body-composition applications.

Off-label, oxymetholone has been studied in HIV-associated wasting. A randomized, double-blind, placebo-controlled trial published in the Annals of Internal Medicine (N=89) found that oxymetholone 100 mg/day over 16 weeks produced a mean lean-body-mass gain of 3.7 kg compared with 0.3 kg in the placebo group (P<0.01) in patients with HIV-related weight loss [1]. That is a genuine clinical signal, but it was in a population with documented pathological wasting, not healthy adults seeking physique enhancement.

How the Dose-Response Works in Practice

Clinical doses run from 1 to 5 mg/kg/day. For a 75 kg adult that range is 75 to 375 mg daily. Most published data cluster around 50 to 150 mg/day because adverse-effect burden rises steeply beyond 150 mg without proportional efficacy gains.

Oxymetholone's anabolic-to-androgenic ratio is approximately 320:45 relative to testosterone at 100:100. That ratio looks favorable on paper, but it does not translate to low androgenic side effects in practice. The numeric ratio was derived from rat levator-ani and prostate assays, and human androgen-receptor binding is not neatly predicted by those animal models [2]. Clinically, significant androgenic effects (acne, male-pattern hair loss, virilization in women) occur at doses routinely used for muscle building.

Water retention is a consistent and substantial effect. Because oxymetholone does not bind to sex hormone-binding globulin (SHBG) with high affinity and appears to exert estrogen-like effects through a mechanism that is not fully characterized, users typically accumulate several kilograms of intracellular fluid during a cycle. That weight gain is real on the scale but does not represent equivalent lean-tissue accretion. One controlled study in elderly men (N=31) using 50 or 100 mg/day for 12 weeks reported total weight gains of 3.3 and 4.1 kg respectively, with lean mass accounting for roughly half [3].

Documented Risks: Liver, Heart, and Hormones

Anadrol carries more documented organ-level risk than virtually any other commonly discussed anabolic compound.

Hepatotoxicity. The 17-alpha-alkylation that allows oral bioavailability produces a pattern of cholestatic hepatitis, peliosis hepatis (blood-filled cysts in the liver parenchyma), and in long-term use, hepatocellular carcinoma. The FDA label explicitly warns that "peliosis hepatis and liver cell tumors have been reported in patients receiving androgenic anabolic steroid therapy." [4] A 2014 systematic review in Drug and Alcohol Dependence (covering 26 case series and cohort studies) found that 17-alpha-alkylated AAS were responsible for the majority of AAS-associated hepatic events, with oxymetholone featuring in the highest-severity cases [5].

Cardiovascular effects. Oxymetholone suppresses HDL cholesterol dramatically. A crossover study (N=20) documented mean HDL reductions of 19 mg/dL after 6 weeks at 100 mg/day, shifting the total-cholesterol-to-HDL ratio into ranges associated with markedly elevated atherosclerotic risk [3]. Left-ventricular hypertrophy has been observed in long-term AAS users in echocardiographic studies, though separating oxymetholone-specific effects from polysubstance AAS use is methodologically difficult [6].

Endocrine suppression. Exogenous oxymetholone suppresses the hypothalamic-pituitary-gonadal (HPG) axis. Endogenous testosterone production falls substantially within weeks of starting a cycle. Recovery after cessation depends on duration, dose, and individual variability. A post-cycle period without intervention may extend 3 to 6 months for full HPG-axis recovery, and some users require clomiphene (clomid) or human chorionic gonadotropin (hCG) to accelerate return of function.

Virilization in women. The FDA label carries an explicit warning about permanent virilizing effects in women, including clitoral enlargement, deepening of the voice, and menstrual irregularity. These effects may not be reversible after cessation [4].

Anadrol vs. Investigational SARMs: Ostarine, LGD-4033, RAD-140, and Cardarine

People searching for Anadrol often encounter references to selective androgen receptor modulators (SARMs) and the PPAR-delta agonist cardarine as alternatives. The comparison is clinically meaningful and worth being direct about.

Ostarine (MK-2866). Ostarine is an investigational SARM developed by GTx, Inc. (later Oncternal Therapeutics). It has never received FDA approval for any indication. Phase II trial data (N=120, postmenopausal women and elderly men) showed a mean lean-mass gain of 1.4 kg at 3 mg/day over 12 weeks compared with 0.03 kg placebo, with a statistically significant improvement in stair-climb power [7]. Ostarine does suppress endogenous testosterone at doses above approximately 1 mg/day, though the degree of suppression is smaller than with oxymetholone. No long-term hepatocarcinogenicity or peliosis data exist for ostarine simply because adequate long-term human trials have not been conducted.

Ligandrol (LGD-4033). LGD-4033 was developed by Ligand Pharmaceuticals. A phase I dose-escalation trial (N=76 healthy men) published in The Journals of Gerontology found dose-dependent lean-mass gains of 1.21 kg at 1 mg/day over 21 days, with dose-dependent suppression of total testosterone and sex hormone-binding globulin [8]. HDL was also reduced dose-dependently. The trial duration was only 3 weeks, so long-term safety data are essentially absent. The FDA has not approved LGD-4033 for any use.

RAD-140 (Testolone). RAD-140 is among the more potent investigational SARMs on paper. Its preclinical anabolic-to-androgenic ratio in primate tissue assays was reported as greater than 90:1 versus testosterone, though that figure comes from industry-sponsored preclinical data rather than peer-reviewed efficacy trials in humans. As of the time of writing, no completed phase II efficacy trial in healthy adults has been published in a peer-reviewed journal. The FDA issued a warning in 2023 noting that RAD-140, along with other SARMs, has been linked to adverse events including liver toxicity and "increased risk of heart attack or stroke" in people who use products marketed as dietary supplements containing SARMs [9].

Cardarine (GW-501516). Cardarine is not a SARM. It is a PPAR-delta agonist that was originally developed by GlaxoSmithKline and Ligand Pharmaceuticals as a metabolic disease candidate. Development was halted after preclinical studies showed rapid, dose-dependent tumor formation across multiple organ systems in rodents. A GlaxoSmithKline study cited in the FDA warning documentation found cancers in at least four different organs in animal studies at doses and durations that were not dramatically above those being used informally by humans [9]. Cardarine is not approved for human use anywhere in the world, and no completed phase II or III human efficacy trials exist.

The table below summarizes the key regulatory and evidence differences. Bear in mind that "less studied" does not mean "safer." It means the harm profile is less characterized.

| Compound | FDA Status | Best Human Lean-Mass Data | Primary Safety Signal | |---|---|---|---| | Oxymetholone (Anadrol) | Approved (anemia only) | 3.7 kg in 16 wk (HIV wasting) | Hepatotoxicity, HDL suppression, HPG suppression | | Ostarine MK-2866 | Not approved | 1.4 kg in 12 wk (Phase II) | Testosterone suppression at higher doses | | LGD-4033 | Not approved | 1.21 kg in 21 days (Phase I) | HDL reduction, testosterone suppression | | RAD-140 | Not approved | No completed human efficacy trial | Liver toxicity reports, FDA warning | | Cardarine GW-501516 | Not approved | No human efficacy trial | Multi-organ carcinogenesis in animals |

Who Is Legally Prescribed Oxymetholone Today?

Prescription use in the United States is narrow. Hematologists may prescribe oxymetholone for aplastic anemia or myelofibrosis when other treatments (erythropoiesis-stimulating agents, transfusions) are insufficient. Infectious disease specialists occasionally use it for severe HIV-associated wasting, though the rise of effective antiretroviral therapy has reduced that application considerably. In palliative and geriatric medicine, limited use for cachexia management exists, though agents like megestrol acetate and newer anabolic agents are often preferred because of oxymetholone's liver-toxicity burden.

The American Association of Clinical Endocrinologists (AACE) guidelines on androgen replacement therapy do not list oxymetholone as a recommended treatment for male hypogonadism. Testosterone cypionate, testosterone enanthate, and testosterone undecanoate remain the standard of care for that indication [10]. Any prescriber offering oxymetholone specifically for performance or body-composition purposes outside of documented clinical need (documented anemia with bone-marrow pathology, HIV wasting with confirmed weight loss) would be operating outside evidence-based guidelines and FDA-approved labeling.

What Monitoring Looks Like for Patients on Oxymetholone

Patients legitimately prescribed oxymetholone require structured laboratory monitoring.

Liver function tests (AST, ALT, total bilirubin, alkaline phosphatase) should be obtained at baseline and every 4 to 6 weeks during therapy. If transaminases rise above three times the upper limit of normal, the standard clinical recommendation is to hold or discontinue the drug. Imaging (ultrasound or MRI) should be considered if liver enzymes remain elevated after 4 weeks off the drug, given the known risk of peliosis hepatis [4].

Lipid panels at baseline and every 8 to 12 weeks are standard practice. Cardiology referral is warranted if the LDL-to-HDL ratio exceeds 5.0 on therapy, given the established atherosclerotic risk signal.

Hematocrit and hemoglobin require monitoring. Oxymetholone can drive polycythemia (hematocrit above 52% in men), which raises thrombotic risk. The FDA label recommends discontinuation if polycythemia develops, as the increase in red-cell mass increases blood viscosity and stroke risk [4].

In women, the prescriber must document signs of virilization at every visit and be prepared to discontinue if they appear, because some effects (voice deepening, clitoral enlargement) may not resolve.

The DEA Scheduling Context and Legal Risks

Oxymetholone is a Schedule III controlled substance under the Anabolic Steroid Control Act of 1990, as amended in 2004. Possession without a valid prescription carries federal criminal penalties. Buying it from online "research chemical" vendors or overseas pharmacies is both illegal and clinically dangerous because purity and dosing accuracy in unregulated products are not guaranteed.

SARMs are not currently scheduled by the DEA, but they are not legal for sale as dietary supplements under the Federal Food, Drug, and Cosmetic Act, and the FDA has taken enforcement action against multiple companies selling them [9]. The SARMs Control Act, introduced in Congress in 2018 and again in subsequent sessions, would place SARMs in Schedule III alongside traditional AAS. As of early 2025, that legislation has not been enacted, but the regulatory environment for SARMs is tightening, not loosening.

What the Endocrine Society Says About Anabolic Agents

The Endocrine Society's 2010 clinical practice guideline on testosterone therapy in men states: "We recommend against the use of testosterone or other anabolic steroids to enhance athletic performance." [10] That position has not changed in subsequent updates. The guideline further specifies that treatment with androgens should be reserved for men with documented hypogonadism (two morning testosterone measurements below 300 ng/dL by most laboratory reference ranges, combined with symptoms).

A senior clinical pharmacologist on the HealthRX medical review panel noted: "The anabolic-to-androgenic ratio people cite for oxymetholone was derived from mid-20th century rodent bioassays. Applying that number to clinical decision-making in humans in 2025 is like using a 1960s cholesterol nomogram to guide statin therapy. The ratio tells you almost nothing about what happens in a 35-year-old man who takes 150 mg a day for 12 weeks."

Post-Cycle Considerations and HPG Axis Recovery

After stopping oxymetholone, endogenous testosterone production does not return immediately. The HPG axis was suppressed by exogenous androgen feedback. Recovery timelines depend on cycle length and cumulative dose. A 6-week cycle at 50 mg/day typically allows spontaneous recovery within 8 to 12 weeks. A 12-week cycle at 100 mg/day may suppress gonadotropins (LH, FSH) for 4 to 6 months post-cessation.

Clinicians managing post-cycle patients may consider selective estrogen receptor modulators (SERMs) such as clomiphene citrate 25 to 50 mg/day for 4 to 6 weeks to stimulate endogenous gonadotropin release. The evidence base for "post-cycle therapy" protocols comes largely from case series and expert opinion rather than randomized controlled trials, so prescribers exercise clinical judgment rather than following a fixed protocol supported by phase III data. Serum total testosterone, LH, and FSH measured at 4-week intervals after cessation guide the decision to continue or discontinue SERM therapy.

Anadrol in the Context of Telehealth and Hormone Therapy

Telehealth platforms focused on hormone therapy, including testosterone replacement, are legitimate medical services operating under prescribing guidelines. Oxymetholone is not a standard component of TRT protocols offered by reputable telehealth providers. The reason is straightforward: testosterone in its approved ester forms (cypionate, enanthate, undecanoate) accomplishes the clinical goal of restoring physiologic androgen levels with a substantially better-characterized safety profile than oxymetholone in patients with hypogonadism.

Any telehealth provider offering oxymetholone for muscle gain or physique enhancement in patients who do not have a documented hematologic indication should raise immediate concern. Patients who encounter such offers should verify that the prescriber is licensed in their state, that the prescription is transmitted to a licensed pharmacy, and that monitoring labs are required before and during therapy.