Loss of libido, decreased hair growth and gynecomastia developed in a 61-year-old man after six months of applying an estrogen-containing hair tincture for diffuse alopecia areata of the head hair. All these signs disappeared within four weeks of stopping the application, and hormone levels were again normal. Locally applied estrogen preparations are in general contraindicated in males because of their potential systemic effects. If they have to be given, hormone levels (testosterone; estradiol) must be checked.
Schmidt KU; Wagner G; Mensing H
Dtsch Med Wochenschr, 112: 23, 1987 Jun 5, 926-8