Oxandrolone
Oxandrolone is characterized by a modification in the basic structure of testosterone to include a substitution of an oxygen atom in place of the methylene group at the C2 position in the steroid ring, this molecule has a 17-alpha-alkylated group at the C17 position that prevents deactivation of this steroid by hepatic first-pass metabolism - allowing for oral administration. Given these alterations, oxandrolone also shows resistance to hepatic metabolism further enhancing action [20]. While mild elevations in hepatic transaminases have been noted [45], oxandrolone is not known for significant hepatic side effects such as cholestasis, peliosis hepatis, hepatic adenomas, and hepatocellular carcinomas. Minor adverse events have been noted in clinical trials on oxandrolone including alterations in cholesterol levels [20].
Similar to nandrolone, oxandrolone has marked anabolic activity, with a myotrophic/androgenic ratio of 10:1 [46]. It has shown clinical efficacy in acute catabolic disorders such as severe burn injuries, after extensive surgery, and severe trauma. There have also been positive clinical outcomes in chronic catabolic disorders such as the treatment of HIV/AIDS-associated wasting [47], neuromuscular diseases such as Duchenne muscular dystrophy [48], amyotrophic lateral sclerosis [45], and COPD [49]. Oxandrolone is also used to offset the protein catabolism associated with long-term corticosteroid use and relief of the bone pain accompanying osteoporosis [20].
As with nandrolone, the reproductive effects of oxandrolone are not well studied. Several case reports note reversible steroid-induced azoospermia with oxandrolone use in combination with other AAS [50, 51]. Caution should be employed in all men of reproductive age given known effects on the LH/FSH axis and the potential resultant effects on spermatogenesis.
Source: Wu, C. & Kovac, J.R. Curr Urol Rep (2016) 17: 72.
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Summary from attached paper.
1. Oxandrolone is an anabolic androgenic steroid (AAS) that has been used for over 30 years in the treatment of various catabolic disorders, HIV and AIDS-related wasting, neuromuscular disorders, and other conditions.
2. The drug shows significant improvements in body composition, muscle strength and function, status of underlying disease or recovery from acute catabolic injury, and nutritional status.
3. Oxandrolone has not yet been studied in sarcopenia, a condition characterized by the loss of skeletal muscle mass and function, commonly seen with advancing age.
4. The use of AASs like oxandrolone as an alternative treatment to promote anabolism in diseases and disorders characterized by sarcopenia is currently under investigation.
5. Oxandrolone is a synthetic, non-reducible or non-aromatisable AAS derived from testosterone but possesses a novel chemical configuration.
6. Unlike other orally administered C17α-alkylated AASs, the novel chemical configuration of oxandrolone confers a resistance to liver metabolism as well as marked anabolic activity.
7. Oxandrolone does not exhibit the serious hepatotoxic effects attributed to the C17α-alkylated AASs. The most common adverse effects are transient elevations in transaminase levels and reductions in high-density lipoprotein cholesterol level.
8. High dosages of oxandrolone did not exacerbate liver function abnormalities or cholestasis in patients with alcoholic hepatitis.
9. Oxandrolone has been shown to decrease visceral fat stores and total body fat.
10. The drug has been used in the treatment of Turner’s syndrome and constitutional delay of growth and puberty.
11. Adverse hepatic events were investigated in 36 (84%) of the 43 studies and 14 (39%) of these reported adverse hepatic events.
12. Androgenic effects were assessed in 27 of the 43 studies. Amongst the approximately 1000 patients in these 27 studies, androgenic adverse effects were reported in only 14 individuals.
13. The low incidence of androgenic adverse effects reported with oxandrolone attests to the more favorable ratio of anabolic: androgenic potency of the drug compared with many other AASs which have been used clinically.
14. Oxandrolone has the potential to exhibit many of the adverse effects associated with AASs, affecting the blood, cardiovascular, central nervous, musculoskeletal, gastrointestinal, renal, reproductive/endocrine, and dermatological systems, as well as psychological and behavioral effects.
15. No cases of prostate cancer have been reported with oxandrolone in the studies reviewed, but longer-term follow-up is required.
16. Oxandrolone is 95% protein bound and its potency can be attributed to its unique structure – an oxygen rather than a carbon atom at position 2 in the A ring.
17. In animal studies, oral oxandrolone had ≤24% of the androgenic activity of methyltestosterone and was demonstrated to be of very low toxicity to mice and rats.
18. The use of AASs in the athletic community, for AASs in this class include oxymetholone, stanozolol, methyltestosterone, metandienone (methandrostenolone), danazol, norethandrolone, and fluoxymesterone.
19. Optimal risk: benefit ratios for oxandrolone and other agents in its class will need to be refined before widespread clinical acceptance of AASs as a therapeutic option in sarcopenia and other chronic wasting conditions.
20. Future studies should follow standardized and rigorous reporting methods for all of the common adverse effects of this medication, so that a more complete profile of the prevalence of these adverse events can be compiled.
