Danazol (Danocrine) is a progestogen sex hormone used orally to treat endometriosis, severe intractable period pain, severe breast pain, and a rare form of severe tissue swelling (familial angioedema). The normal dose is one capsule two to four times a day for three to nine months.
It must not be used during pregnancy, breastfeeding or in children. Women taking danazol must use adequate non-hormonal contraception. Its use is also prohibited if suffering from undiagnosed genital disease, severe liver disease, a pelvic infection, cancer of any sex organs, heart failure, a recent blood clot or porphyria. It must be used with caution by patients with liver disease, high blood pressure, heart disease and diabetes. Regular blood tests to check liver function are recommended.
Common side effects include acne, weight gain, fluid retention, excess body hair growth, voice deepening, flushing, sweating, dry vagina and menstrual period irregularities. Unusual effects may include oily skin, hoarseness, reduced breast size, enlargement of clitoris and nervousness. Rarely yellow skin (jaundice), a blood clot in vein and chest pain (embolism) may occur.
Interactions are possible between danazol and warfarin, carbamazepine, cyclosporin, oral contraceptives, phenytoin, steroids and diabetes medications. An overdose causes vomiting, tissue swelling and indigestion.
Danazol is a very effective medication, but significant side effects a problem for some patients. It is used for six to nine months only and does not cause addiction or dependence.