To the editor: Danazol®, a synthetic steroid that inhibits pituitary gonadotropins (1), is effective in preventing attacks of hereditary angioedema (2). Side effects are minor, the commonest being menstrual irregularities or amenorrhea, weight gain, edema, and acne (3). Muscle aching has been mentioned without reference to the plasma level of creatine phosphokinase (CPK) (3, 4). The following summary describes the case of a patient with hereditary angioedema whose attacks stopped when she took Danazol but who had muscle cramps and aching with elevated CPK levels until Danazol was withdrawn.
The patient, a 40-year-old woman, began to have bouts of abdominal