Danazol

To the Editor.— An article in MEDICAL NEWS (233:942-943, 1975) gave special reference to danazol. Having worked with this new medication1and having heard the article presented by Dr Niels H. Lauersen in Los Angeles at the April meeting of the American Fertility Society, I must take exception to the implication that danazol causes permanent relief of the symptoms of endometriosis, especially since the follow-up period after the medication is discontinued is inadequate (by Dr Lauersen's admission to my question from the floor in Los Angeles). Active endometriosis does recur, with its attendant symptoms, within eight to 12 months after danazol therapy is stopped. Certainly this medication may prove to be beneficial, but let us not go overboard until we thoroughly assess these patients for a long enough period of time after the therapy is discontinued. I realize that reference was made to Greenblatt's study of danazol: The drug