Oxandrolone(Oxandrin) is adrugcreated bySearle Laboratories, nowPfizer Inc.under the
trademarkAnavar, and introduced into the US in 1964.
Oxandrolone is a syntheticanabolic steroidderived
fromdihydrotestosteroneby substituting 2nd carbon atom for oxygen
(O). It is widely known for its exceptionally small level of
androgenicity accompanied by moderate anabolic effect. Although
oxandrolone is a 17-alpha alkylated steroid, 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 notaromatize(convert to
estrogen, which causesgynecomastiaor male breast tissue). It also
does not significantly influence the body's normal testosterone
production (HPTA axis) at low dosages (10 mg). When dosages
are high, the human body reacts by reducing the production of LH
(luteinizing hormone), thinkingendogenoustestosterone production is
too high; this in turn eliminates further stimulation of Leydig
cells in thetesticles, causingtesticular atrophy(shrinking).
Oxandrolone used in a dose of 80 mg/day suppressed endogenous
testosterone by 67% after 12 weeks of therapy.
The drug was prescribed to promote muscle regrowth in disorders
which cause involuntary weight loss. It had also been shown to be
partially successful in treating cases ofosteoporosis. However, in
part due to bad publicity from its abuses bybodybuilders,
production of Anavar was discontinued by Searle Laboratories in
1989. It was picked up by Bio-Technology General Corporation,
nowSavient Pharmaceuticalswho, following successful clinical trials
in 1995, released it under the tradename Oxandrin. As of 2009, it
is the only drug marketed by the company.
It was subsequently approved fororphan drugstatus by theFood and
Drug Administration(FDA) for treating alcoholic hepatitis,Turner
syndrome, andweight losscaused byHIV. It is also indicated as an
offset toprotein catabolismcaused by long-term administration
ofcorticosteroids. In addition, the drug has shown positive results
in treatinganemiaandhereditary angioedema. Because of its potential
for abuse, it is categorized as aSchedule IIIcontrolled substance
in the US.
In a randomized, double-blind study, patients with 40% total body
surface areaburnswere selected to receive standard burn care plus
oxandrolone, or without oxandrolone. Those treated with oxandrolone
showed improved body composition, preservedmuscle massand reduced
hospital stay time.