[Therapy of alopecia areata with diphenylcyclopropenone]

Induction and maintenance of contact dermatitis of the scalp has proved effective in producing regrowth of hair in patients with alopecia areata. We observed regrowth of hair in 17 out of 20 patients after local application of the contact allergen, diphenylcyclopropenone. Only 3 patients were treated without success. In 3 patients regrowth of hair was also seen in areas that were not treated with diphenylcyclopropenone, suggesting that this treatment has an additional systemic effect. Patient acceptance of the induced dermatitis was excellent.