Leuprolide overstimulates the body's own production of certain hormones, which causes that production to shut down temporarily. Leuprolide reduces the amount of testosterone in men or estrogen in women. Leuprolide is used in men to treat the symptoms of prostate cancer. Leuprolide treats only the symptoms of prostate cancer and does not treat the cancer itself. Leuprolide is used in women to treat symptoms of endometriosis (overgrowth of uterine lining outside of the uterus) or uterine fibroids. Leuprolide is also used to treat precocious (early-onset) puberty in both male and female children. Leuprolide may also be used for purposes not listed in this medication guide.