Danazol, an isoxazol derivative of 17 a -ethinyltestosterone, causes anovulation by attenuating the midcycle surge of luteinizing hormone secretion, inhibiting multiple enzymes in the steroidogenic pathway, and increasing serum free testosterone concentrations. The recommended dosage of danazol for the treatment of endometriosis is 600 to 800 mg per day; however, these doses have substantial androgenic side effects such as increased hair growth, mood changes, a deepening of the voice that may be irreversible, adverse effects on serum lipids, and rarely, liver damage that may be irreversible and life-threatening. Studies of lower doses have usually been uncontrolled or small