Oxandrolone, sold under the brand names Oxandrin and Anavar, among others, is an androgen and anabolic steroid (AAS) medication which is used to help promote weight gain in various situations, to help offset protein catabolism (breakdown) in people with HIV/AIDS, and to help treat osteoporosis. It is taken by mouth. Common side effects of oxandrolone include symptoms of masculinization like acne, increased hair growth, voice changes, and increased sexual desire. It can also cause liver damage. The drug is a synthetic androgen and anabolic steroid and hence is an agonist of the androgen receptor (AR), the biological target of androgens like testosterone and dihydrotestosterone (DHT). It has moderate anabolic effects and weak androgenic effects, as well as no estrogenic effects or risk of liver damage. The drug has moderate bioavailability, due in part to an active metabolite. Oxandrolone was discovered in 1962 and was introduced for medical use in 1963. It is used mainly in the United States, and is rarely used in the United Kingdom and Canada due to the availability of other drugs with fewer side effects. Oxandrolone is a controlled substance in the United States and many other countries, and so while it is not commonly prescribed, it is often used by bodybuilders and athletes, and is sold illegally as a performance-enhancing drug.
Medical uses of the drug include treatment of HIV/AIDS, promoting weight gain after a period of weight loss (e.g., after surgery or due to a disease like cancer), and promoting weight gain in people who are overweight or underweight (e.g., due to cancer, HIV/AIDS, or an eating disorder). Oxandrolone is used to treat HIV/AIDS-associated weight loss. It is a short-term treatment option for people with muscle wasting due to severe burns, cancer, and other causes. The efficacy of oxandrolone for HIV-associated weight loss is based on results from a single randomized controlled trial of 113 women with HIV/AIDS-associated wasting, discontinued early for benefit. No good evidence shows that oxandrolone is effective for weight loss in people with cancer who have recently lost weight or those with cancer cachexia (wasting syndrome). Oxandrolone is used to treat osteoporosis. The drug has been shown to increase bone mineral density (BMD) by 12.5% in men aged 50 and over, and by 6.9% in men aged 70 and over, and by 9.2% at the lumbar spine in men aged 50 and over. It has also been shown to increase BMD in women aged 50 and over, with a 9.3% increase seen at the lumbar spine. BMD was also found to increase more in lumbar spine than in femoral neck.
The World Anti-Doping Agency removed oxandrolone from its list of prohibited substances in 2004. In the United States, the Food and Drug Administration approved oxandrolone in 2005 for use in males who have low testosterone levels. Oxandrolone is under investigation as a potential male contraceptive. Oxandrolone is used for physique- and performance-enhancing purposes by competitive athletes, bodybuilders, and powerlifters. In the United States, oxandrolone is a Schedule III controlled substance under the Controlled Substances Act of 1970 and is illegal to possess without a prescription. Oxandrolone is banned by the World Anti-Doping Agency. A 2005 survey conducted on competitive bodybuilders reported that 74% of them used oxandrolone. The drug is used by athletes from all over the world, including track and field athletes like Yuriy Bilonog, Kareem Streete-Thompson, Nicola Rogers, and Frank Fredericks, and soccer players like Landon Donovan, Gary Ablett, Jr., Reto Ziegler, and Diego Costa. Oxandrolone is sometimes used in conjunction with other AAS to achieve a synergistic effect. It is often used in the cutting phase of bodybuilding along with the milder AAS like stanozolol and methenolone enanthate, with which it has a synergistic effect, and which are particularly useful for preserving lean tissue while on a reduced calorie diet. Oxandrolone is also sometimes used to counteract the androgenic side effects of anabolic steroids like testosterone and nandrolone.
Risks of use include increased risk of cardiovascular disease and high blood pressure. Oxandrolone, also known as 17α-hydroxy-17β-hydroxy-4-androsten-3-one or as 17α-hydroxy-17β-hydroxy-4-androsten-3-one, is a synthetic androstane steroid and a 17α-hydroxy steroid. It is the C17α acetate ester of oxandrolone, also known as 4-androstenediol (4-AD), the 4-androstenediol. Oxandrolone was synthesized in 1962 in Randall Lab at the University of California at Berkeley by biochemist William N. Patrick, Jr. It was the first clinically available anabolic steroid to be isolated from the human body, and the first to be identified in a laboratory. Oxandrolone was first sold in 1964 by Ciba Specialty Chemicals under the trademark name Anavar. Oxandrolone has been marketed under a variety of brand names including Anavar, Anatrophill, Andriol, Biomaglan-V, Lipidex, Lipidex C, Lipidex S, Oxanabol, Oxandrin, Oxandrol, Oxandrin, Oxanorm, Oxasteron, Oxas, Oxatron, Oxybolin, Stanolone, Stanolone, Stanzol, Steranabol, and Superanabol. Oxandrolone is available in the United States and Canada under the brand name Anavar as 5, 10, and 40 mg tablets and an oral solution (dropped from the market in July 2011). The drug was previously available in the U.S. under the brand name Oxandrin, but this trade name was discontinued in June 2001. In the U.S., the generic name is also available. Internationally, oxandrolone is available under many brand names including Anatrophill, Biomaglan-V, and Oxanabol. It is also available in generic form. The U.S. patent for oxandrolone expired in November 2002. Oxandrolone is prohibited under the World Anti-Doping Agency (WADA) and is on the List of Prohibited Substances and Methods.