Fluoxymesterone, sold under the brand names Halotestin and Ultandren among others, is a synthetic, orally active androgenic-anabolic steroid (AAS) and a 17α-alkylated derivative of testosterone. It is generally regarded as a very strong oral anabolic steroid that is unable to aromatize into Estrogen and also exhibits very strong androgenic strength as well.
Halotestin, is one of the most powerful anabolic-androgenic steroids out there. In the world of performance enhancement, Halotestin holds a reputation of being one of the most powerful and fast acting steroids on the market. Like the others, it is a derivative of the steroid testosterone. Its primary function is not as a performance enhancing drug but as a testosterone replacement for those experience growth problems. As a gonadal steroid it induces puberty among male teenagers. It also works as an anti-estrogen for women who have breast cancer.