Accidental observation of early cure of lichen planus in a female patient who received propranalol for the treatment of associated hyperthyroidism made us to try this drug in 20 patients with lichen planus. The cutaneous lesions responded very well to the treatment in 909'o of the cases. The mucous membrane lesions responded only partially and slowly. Another group of 20 patients with lichen planus who received only oral pheniramine maleate showed persistence of skin lesions even after 3 months. There were no serious side effects -with propranalol, though one patient with an atopic background, developed bronchial asthma for the first time at the age of 21. The excellent therapeutic response to propranalol-a beta-adrenergic receptor blocker, in these patients indicates further study.