The USE of hormones in the treatment of acne is not new. Lawrence and Werthessen1in 1942 proposed the thesis that acne is caused by a disturbance of the normal balance between androgens and estrogens. According to their theory, when the unbalance becomes such that there is a preponderance of the androgens, the acnegenic action of the androgens which Hamilton2demonstrated is exerted. Urbach2in 1939 claimed that the aggravation of acne during the premenstrual phase was due to the presence of an endogenous allergen in the blood of such patients. Apparently Zondek and Bromberg4had similar views because they were able to demonstrate by hormone injection a dermal sensitivity not only in asthma, migraine and pruritus vulvae but also in acne vulgaris. On the other hand, MacKenna5expressed the belief that Barber and Bishop6showed conclusively "that in the causation of acne