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 caused by long-term corticosteroid therapy, to support recovery from severe burns, to treat bone pain associated with osteoporosis, to aid in the development of girls with Turner syndrome, and for other indications. It is taken by mouth.
Many bodybuilders and athletes use oxandrolone illicitly for its muscle-building effects.[5] It is much more anabolic than androgenic, so women and those seeking less intense steroid regimens use it particularly often. Many also value oxandrolone's low hepatotoxicity relative to most other orally active AASs.
Oxandrolone has been researched and prescribed as a treatment for a wide variety of conditions. It was FDA-approved for treating bone pain associated with osteoporosis, aiding weight gain following surgery or physical trauma, during chronic infection, or in the context of unexplained weight loss, and counteracting the catabolic effect of long-term corticosteroid therapy.
Like other AASs, oxandrolone is an agonist of the androgen receptor, similar to androgens such as testosterone and DHT. The relative binding affinity of oxandrolone for the androgen receptor is about 0.3% of that of metribolone. Activation of the androgen receptor stimulates protein synthesis, which increases muscle growth, lean body mass, and bone mineral density.
Compared to testosterone and many other AASs, oxandrolone is less androgenic relative to its strength as an anabolic. Oxandrolone has about 322 to 633% of the anabolic potency and 24% of the androgenic potency of methyltestosterone.
Similarly, oxandrolone has as much as 6 times the anabolic potency of testosterone and has significantly reduced androgenic potency in comparison. The reduced ratio of anabolic to androgenic activity of oxandrolone often motivates its medical use in children and women because less androgenic effect implies less risk of virilization.
The bodybuilding community also considers this fact when choosing between AASs.
Oxandrolone is an anabolic steroids indicated as adjunctive therapy to promote weight gain after weight loss following extensive surgery, chronic infections, or severe trauma, and in some patients who without definite pathophysiologic reasons fail to gain or to maintain normal weight, to offset the protein catabolism associated with prolonged administration of corticosteroids, and for the relief of the bone pain frequently accompanying osteoporosis. Anabolic steroids are synthetic derivatives of testosterone.
Oxandrolone greatly increases warfarin's blood-thinning effect, sometimes dangerously so. In April 2004, Savient Pharmaceuticals published a safety alert through the FDA warning healthcare professionals of this. Oxandrolone can also inhibit the metabolism of oral hypoglycemic agents. It may worsen edema when taken alongside corticosteroids or adrenocorticotropic hormone.
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.[5] It had also been shown to be partially successful in treating cases of osteoporosis.
Metabolism: The oral bioavailability of oxandrolone is 97%. Its plasma protein binding is 94 to 97%. The drug is metabolized primarily by the kidneys and to a lesser extent by the liver. Oxandrolone is the only AAS that is not primarily or extensively metabolized by the liver, and this is thought to be related to its diminished hepatotoxicity relative to other AASs.
Absorption: Well absorbed following parenteral administration.
Route of elimination: About 28% of an oral dose of oxandrolone is eliminated unchanged in the urine and 3% is excreted in the feces.
Half life: Its elimination half-life is reported as 9.4 to 10.4 hours, but is extended to 13.3 hours in the elderly.
All medicines may cause side effects, but many people have no, or minor, side effects. Some medical conditions may interact with Oxandrolone.
Tell your doctor or pharmacist if you have any medical conditions.
Women who are administered oxandrolone may experience virilization, irreversible development of masculine features such as voice deepening, hirsutism, menstruation abnormalities, male-pattern hair loss, and clitoral enlargement. Because of these side effects, doses given to women and children are minimized and people are usually monitored for virilization and growth abnormalities. Like other androgens, oxandrolone can cause or worsen acne and priapism (unwanted or prolonged erections). Oxandrolone can also reduce males' fertility, another side effect common among androgens. In an attempt to compensate for the exogenous increase in androgens, the body may reduce testosterone production via testicular atrophy and inhibition of gonadotropic activity.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider.
