Stanozolol is an oral androgen derived from dihydrotestosterone. Stanozolol acts on androgen receptors to promote anabolism through increased nitrogen retention and protein synthesis in muscle tissue. Stanozolol is a strong anabolic substance with androgenic action. Stanozolol does not convert to estrogen and therefore does not produce typical estrogen mediated side effects such as water retention. Stanozolol has a large oral bioavailability, due to a C17 a-alkylation which allows the hormone to survive first pass liver metabolism. Stanozolol reduces SHBG increasing free testosterone levels.