|Systematic (IUPAC) name|
|Mol. mass||306.44 g/mol|
|(what is this?)|
Oxandrolone, also known as oxandrin, is a drug first synthesized by Raphael Pappo while at Searle Laboratories, now Pfizer Inc., under the trademark Anavar, and introduced into the United States in 1964. It is a synthetic anabolic steroid derivative of dihydrotestosterone with an oxygen atom replacing the 2 carbon and methylation in the 17 position.
Oxandrolone is widely used due to its exceptionally small level of androgenicity accompanied by moderate anabolic effect. Although oxandrolone is a 17-alpha alkyloid, its liver toxicity is very small as well. Studies have showed that a daily dose of 20 mg oxandrolone used in the course of 12 weeks had only a negligible impact on the increase of liver enzymes. As a DHT derivative, oxandrolone does not aromatize (convert to estrogen, which causes gynecomastia or male breast tissue). It also does not significantly influence the body's normal testosterone production (HPTA axis) at low dosages (20 mg). When dosages are high, the human body reacts by reducing the production of LH (luteinizing hormone), thinking endogenous testosterone production is too high; this in turn eliminates further stimulation of Leydig cells in the testicles, causing testicular atrophy (shrinking). Oxandrolone used in a dose of 20 mg/day suppressed endogenous testosterone by 67% after 12 weeks of therapy.
In a randomized, double-blind study, patients with 40% total body surface area burns were selected to receive standard burn care plus oxandrolone, or without oxandrolone. Those treated with oxandrolone showed improved body composition, preserved muscle mass and reduced hospital stay time.
The drug was prescribed to promote muscle regrowth in disorders which cause involuntary weight loss, and is used as part of treatment for HIV/AIDS. It had also been shown to be partially successful in treating cases of osteoporosis. However, in part due to bad publicity from its abuses by bodybuilders, production of Anavar was discontinued by Searle Laboratories in 1989. It was picked up by Bio-Technology General Corporation, now Savient Pharmaceuticals who, following successful clinical trials in 1995, released it under the tradename Oxandrin.
It was subsequently approved for orphan drug status by the Food and Drug Administration (FDA) for treating alcoholic hepatitis, Turner syndrome, and HIV-induced weight loss. It is also indicated as an offset to protein catabolism caused by long-term administration of corticosteroids. In addition, the drug has shown positive results in treating anemia and hereditary angioedema. Because of its potential for abuse, it is categorized as a Schedule III controlled substance in the United States.
Oxidation of the 2-enone in with lead tetraacetate may proceed through the initial formation of a 1,2,3 tricarbonyl compound; this undergoes ring scision and eventual loss of carbon 2 to give acidaldehyde, which is in equilibrium with the lactol form. Reduction with sodium borohydride leads to the lactone oxandrolone.
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- Pappo, R.; Jung, C. J. (1962). "2-oxasteroids: A new class of biologically active compounds". Tetrahedron Letters 3 (9): 365. doi:10.1016/S0040-4039(00)70883-5.
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- Hart DW, Wolf SE, Ramzy PI, Chinkes DL, Beauford RB, Ferrando AA, Wolfe RR, Herndon DN (April 2001). "Anabolic effects of oxandrolone after severe burn". Ann. Surg. 233 (4): 556–64. doi:10.1097/00000658-200104000-00012. PMC 1421286. PMID 11303139.
- Przkora R, Herndon DN, Suman OE (January 2007). "The effects of oxandrolone and exercise on muscle mass and function in children with severe burns". Pediatrics 119 (1): e109–16. doi:10.1542/peds.2006-1548. PMC 2367234. PMID 17130281.
- Demling RH, DeSanti L (December 2003). "Oxandrolone induced lean mass gain during recovery from severe burns is maintained after discontinuation of the anabolic steroid". Burns 29 (8): 793–7. doi:10.1016/j.burns.2003.08.003. PMID 14636753.
- Oxandrin Homepage, savientpharma.com (retrieved 23 October 2009)* Oxandrin Label, fda.gov (retrieved 23 October 2009)
- "Oxandrolone Side Effects, Interactions and Information". drugs.com.