Educational reference only. Informational material drawn from peer-reviewed literature. Not medical advice and not a recommendation to use, dose, or modify any therapy. Decisions about hormone therapy should be made with a qualified healthcare provider.
Overview
Overview
Oxandrolone is a synthetic anabolic-androgenic steroid (AAS), best known by the trade name Anavar. It is one of the few AAS with a uniquely favorable safety profile relative to most other compounds in its class, characterized by minimal androgenic activity, no aromatization to estrogen, and substantially lower hepatotoxicity than other 17α-alkylated oral steroids. Oxandrolone is the only AAS currently FDA-approved for restitution of weight loss after severe trauma, major surgery, infections, and certain other catabolic conditions.
Originally synthesized in 1962 by GD Searle and marketed as Anavar, oxandrolone has been used in clinical medicine for over six decades. Its modern legitimate medical applications include:
- Severe burn injury: most clinically established indication, with strong RCT evidence
- HIV/AIDS-related muscle wasting (designated an orphan drug by FDA for this use)
- Duchenne and Becker muscular dystrophy
- Recovery from major surgery, severe trauma, prolonged corticosteroid therapy
- Alcoholic hepatitis
- Bone pain associated with osteoporosis
Like other 17α-alkylated oral steroids, oxandrolone does not require an ester for oral bioavailability.
Forms
Available forms & half-lives
| Form | Approximate half-life |
|---|---|
| Oxandrolone (oral tablet, not esterified) | ~9 hours |
What it does
Main effects
- Strong anabolic activity with minimal androgenic effects: among the highest anabolic-to-androgenic ratios of any AAS (~322–630:24 in animal assays)
- No aromatization to estrogen: does not produce water retention, gynecomastia, or estrogen-mediated effects; unlike oxymetholone, does not produce paradoxical estrogenic effects either
- Orally bioavailable (~97% bioavailability) without injection: the 17α-methyl modification permits oral dosing
- Improved wound healing and recovery demonstrated in severe burn patients PMC: 12370634
- Most favorable cardiovascular profile of any orally bioavailable AAS: lipid changes occur but are less pronounced than other oral compounds
- Most favorable virilization profile for female use, though risk is reduced rather than absent
What to watch for
Common side effects
- Hepatotoxicity: substantially milder than other 17α-alkylated AAS but still requires monitoring; the 17α-methyl modification still carries some hepatic risk
- HDL reduction (20–30% at therapeutic doses) and LDL elevation: less severe than oxymetholone or stanozolol but clinically meaningful
- HPG axis suppression: generally less severe than more potent AAS; recovery generally faster than with longer-acting compounds
- SHBG reduction: potentially increases bioavailability of other circulating androgens
- Modest erythrocytosis: less pronounced than most other AAS
- Mild acne and androgenic skin effects: generally less severe than more androgenic compounds
- Scalp hair loss in genetically predisposed users: 5α-reductase inhibitors do not protect (oxandrolone is already 5α-reduced)
- Virilization risk in women: voice changes and clitoral enlargement can occur and may be irreversible, though risk is lower than with other AAS
- Major counterfeiting concern: among the most-counterfeited AAS; products labeled "Anavar" frequently contain other (often worse) compounds like dianabol, stanozolol, or methylated testosterone
Key facts
Key facts worth knowing
- Oxandrolone is 17α-alkylated, meaning it carries some inherent hepatotoxic potential. However, the hepatotoxicity is substantially milder than other oral AAS like oxymetholone, methandrostenolone, or stanozolol. Clinical trial data shows acceptable safety profile with appropriate monitoring.
- The compound has the most favorable cardiovascular profile of any orally bioavailable AAS in terms of lipid changes: HDL reductions and LDL elevations occur but are less pronounced than with other oral compounds.
- The anabolic-to-androgenic ratio is approximately 322-630:24 (in animal assays), making it one of the most "anabolic-selective" AAS. This is the structural basis for its reputation as relatively suitable for female users, though virilization risk is not absent.
- Strong RCT evidence base in burn treatment: a 2023 systematic review and meta-analysis of 19 trials with 2,006 patients demonstrated significant reductions in weight loss during catabolic phase, hospital length of stay, and operation times. PMC: 12370634
- Foundational HIV wasting trial: Berger et al. (1996) demonstrated efficacy at 5 mg/day and 15 mg/day for weight gain in HIV-seropositive men with wasting. PMID: 8970686
- Originally developed by GD Searle, the same company that brought Aldactone (spironolactone) and Norpace (disopyramide) to market. Searle marketed Anavar in the United States until the 1990s.
Legal status
Legal status
Schedule III controlled substance in the United States (DEA). FDA-approved as Anavar/Oxandrin for the indications listed above. WADA-prohibited at all times in competitive sport.