Oxandrolone

Oxandrolone exerts its anabolic effects primarily through binding to the intracellular androgen receptor (AR), promoting nitrogen retention and protein synthesis in skeletal muscle tissue. As a DHT derivative, it cannot be converted to estrogen by the aromatase enzyme, which means it does not cause estrogen-mediated water retention or gynecomastia. The 2-oxo modification in the A-ring reduces its affinity for 5-alpha reductase, limiting conversion to more potent androgens in peripheral tissues and contributing to its relatively low androgenic profile. Oxandrolone increases protein synthesis through direct AR-mediated gene transcription, enhances the expression of genes involved in muscle hypertrophy and repair, and promotes collagen synthesis. It has also been shown to reduce cortisol-binding globulin levels and attenuate the catabolic effects of glucocorticoids, which is particularly relevant in burn patients and those recovering from severe trauma. Additionally, oxandrolone stimulates hepatic production of sex hormone-binding globulin (SHBG) to a lesser degree than other oral steroids, though it does suppress endogenous testosterone production through negative feedback on the hypothalamic-pituitary-gonadal axis.