Leuprorelin, also known as leuprolide, is a manufactured version of a hormone used to treat prostate cancer, breast cancer, endometriosis, uterine fibroids, and early puberty. It is given by injection into a muscle or under the skin. Leuprorelin, also known as leuprolide, is a manufactured version of a hormone used to treat prostate cancer, breast cancer, endometriosis, uterine fibroids, and early puberty. It is given by injection into a muscle or under the skin. Common side effects include hot flashes, unstable mood, trouble sleeping, headaches, and pain at the site of injection. Other side effects may include high blood sugar, allergic reactions, and problems with the pituitary gland. Use during pregnancy may harm the baby. Leuprorelin is in the gonadotropin-releasing hormone (GnRH) analogue family of medications. It works by decreasing gonadotropin and therefore decreasing testosterone and estradiol. Leuprorelin was patented in 1973 and approved for medical use in the United States in 1985. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. In the United Kingdom a monthly dose costs the NHS about GB£75.24. In the United States the equivalent dose has a wholesale cost of US$1,011.93. It is sold under the brand name Lupron among others. Leuprorelin may be used in the treatment of hormone-responsive cancers such as prostate cancer and breast cancer. It may also be used for estrogen-dependent conditions such as endometriosis or uterine fibroids. It may be used for precocious puberty in both males and females, and to prevent premature ovulation in cycles of controlled ovarian stimulation for in vitro fertilization (IVF). It may be used to reduce the risk of premature ovarian failure in women receiving cyclophosphamide for chemotherapy. Leuprorelin, along with triptorelin and goserelin, are often used to delay puberty in transgender youth until they are old enough to begin hormone replacement therapy. They are also sometimes used as alternatives to antiandrogens like spironolactone and cyproterone acetate for suppressing testosterone production in transgender women. It is considered a possible treatment for paraphilias. Leuprorelin has been tested as a treatment for reducing sexual urges in pedophiles and other cases of paraphilia. Common side effects of Lupron Injection include redness/burning/stinging/pain/bruising at the injection site, hot flashes (flushing), increased sweating, night sweats, tiredness, headache, upset stomach, nausea, diarrhea, constipation, stomach pain, breast swelling or tenderness, acne, joint/muscle aches or pain, trouble sleeping (insomnia), reduced sexual interest, vaginal discomfort/dryness/itching/discharge, vaginal bleeding, swelling of the ankles/feet, increased urination at night, dizziness, breakthrough bleeding in a female child during the first 2 months of leuprorelin treatment, weakness, chills, clammy skin, skin redness, itching, or scaling, testicle pain, impotence, depression, or memory problems. The rates of gynecomastia with leuprorelin have been found to range from 3 to 16%.