 It is also used in the treatment of Klinefelter's syndrome, aplastic anemia, Cushing's syndrome (as an anabolic to preserve lean body mass), postmenopausal osteoporosis in women, advanced breast cancer in women, breast pain in women, and cachexia.Testosterone isobutyrate has been used in masculinizing hormone therapy for transgender men as well.Testosterone isobutyrate is provided in the form of a 25 mg/mL microcrystalline aqueous suspension packaged in 2 mL ampoules (5 ampoules per box).