Anadrol (oxymetholone) is a powerful oral anabolic steroid that stimulates red blood cell production and promotes rapid gains in muscle mass and strength. It is FDA-approved to treat certain types of anemia, but it’s widely known in bodybuilding circles as one of the strongest oral steroids available. It is also a Schedule III controlled substance in the United States, meaning non-prescription use is illegal.
How Anadrol Works in the Body
For decades, scientists assumed Anadrol worked by boosting erythropoietin (EPO), the hormone your kidneys release to signal red blood cell production. That assumption turned out to be wrong. Research published in Stem Cell Reports found that oxymetholone has no effect on EPO signaling at all. Mice given the drug showed the same EPO levels as mice given a placebo, and gene analysis of early blood cell precursors showed zero activation of EPO-related genes.
What Anadrol actually does is more direct. It binds to androgen receptors and suppresses a protein called osteopontin, which normally acts as a brake on blood stem cell proliferation. By turning down that brake more than tenfold, Anadrol lets blood-forming stem cells multiply faster, producing more red blood cells. More red blood cells means better oxygen delivery to tissues, which is why the drug was developed to treat anemia and why athletes associate it with improved endurance and fuller-looking muscles.
FDA-Approved Medical Uses
Anadrol’s only approved indication is the treatment of anemias caused by deficient red blood cell production. That includes acquired aplastic anemia, congenital aplastic anemia, myelofibrosis, and anemias triggered by bone marrow-suppressing medications. These are serious conditions where the body simply cannot make enough red blood cells on its own, and Anadrol can help bridge that gap while other treatments take effect or when other options have failed.
Effects on Muscle Mass and Strength
The reason most people search for Anadrol isn’t anemia. It’s the drug’s reputation for dramatic changes in body composition, and the clinical data backs that up. A 24-week randomized, placebo-controlled trial in hemodialysis patients found that those taking oxymetholone gained an average of 3.2 kg (about 7 pounds) of fat-free mass while simultaneously losing about 1.3 kg (roughly 3 pounds) of body fat. The placebo group saw no comparable changes.
Strength increased too. Handgrip strength in the oxymetholone group improved by an average of 2.6 kg more than in the placebo group. Perhaps more telling, muscle biopsies revealed that the cross-sectional area of type I (slow-twitch) muscle fibers grew significantly more in the drug group. These were sick patients on dialysis, not athletes in a gym, so the effects in healthy individuals training intensely are generally considered to be substantially greater.
The weight gain with Anadrol is famously fast but also somewhat misleading. A significant portion of the initial size increase comes from water retention, not pure muscle tissue. This is why people often report looking noticeably bigger within the first week or two, but also why much of that size can disappear quickly after stopping the drug.
Side Effects on the Liver
Anadrol belongs to a class called 17-alpha-alkylated steroids, meaning it has been chemically modified to survive passing through the liver when swallowed. That modification is what makes it effective as a pill, but it also makes the liver work hard to process it. This is the drug’s most well-known risk.
Liver enzyme elevations are common during use, though they tend to be modest. Levels of ALT and alkaline phosphatase typically stay below two to three times the upper limit of normal. Counterintuitively, these enzyme numbers can appear relatively low even when more serious damage is occurring.
The more dangerous liver risk is a condition called peliosis hepatis, where blood-filled cysts develop throughout the liver tissue. The liver becomes enlarged, deep red, and fragile. Most cases are discovered incidentally on imaging or during unrelated procedures, but in severe cases, the liver can rupture, causing sudden abdominal pain and potentially life-threatening internal bleeding. The good news is that peliosis associated with anabolic steroids usually reverses, at least partially, once the drug is stopped.
Effects on Cholesterol
Anadrol’s impact on blood lipids is among the harshest of any anabolic steroid. Anabolic steroid use in general can raise LDL (“bad”) cholesterol by more than 20% while slashing HDL (“good”) cholesterol by 20% to 70%. Oral steroids like Anadrol tend to hit the hardest because the liver processes them directly, and the liver is where HDL cholesterol is manufactured. This shift in the cholesterol ratio significantly increases cardiovascular risk, particularly with prolonged use.
These lipid changes begin quickly after starting the drug and can persist for weeks or months after stopping. For someone already carrying risk factors like high blood pressure, excess body weight, or a family history of heart disease, this effect compounds an already elevated baseline risk.
Other Notable Side Effects
Beyond the liver and cholesterol, Anadrol carries the full range of side effects you’d expect from a potent androgenic steroid:
- Water retention and bloating: Anadrol causes significant fluid accumulation, which can raise blood pressure and obscure muscle definition.
- Hormonal suppression: The body’s natural testosterone production shuts down rapidly during use. Recovery after stopping can take months and sometimes requires medical intervention.
- Estrogenic effects: Despite not converting to estrogen through the usual pathway, Anadrol can cause gynecomastia (breast tissue growth in men) through mechanisms that aren’t fully understood.
- Androgenic effects: Acne, oily skin, hair loss in those predisposed to male-pattern baldness, and in women, deepening of the voice and facial hair growth.
Legal Status
Oxymetholone is classified as a Schedule III controlled substance by the DEA. Possessing it without a valid prescription is a federal offense, and purchasing it from underground labs or overseas sources carries both legal and health risks, since unregulated products may contain incorrect doses, contaminants, or different compounds entirely. Prescriptions for Anadrol are rare and limited almost exclusively to the anemia indications described above.