Halotestin (Fluoxymesterone) is an oral anabolic-androgenic steroid (AAS) that is derived from testosterone. It is used primarily for medical purposes to treat conditions such as delayed puberty and hypogonadism (low testosterone levels) in men. It is not approved for use in women. Competitive athletes and bodybuilders sometimes use halotestin to improve their physical performance and appearance, but this is considered illegal and can have serious health consequences. Halotestin acts by increasing the levels of androgenic hormones in the body and thus contributing to the development of muscle mass and strength. It is also used to treat breast cancer in women and to reduce inflammation and swelling caused by some medical conditions. Halotestin is taken orally, and the dosage and duration of treatment depend on the individual's needs and response. The medication can have some side effects; these include acne, oily skin, hair loss, increased body hair growth, sleep problems, and headaches.