Abstract The effectiveness of levodopa in the treatment of restless legs was assessed in a double-blind trial. 20 patients were given levodopa and lactose on alternate days. Treatment was continued until patients stated a preference for one of the treatments or were unable to discriminate between the two. 17 patients preferred levodopa, none lactose, and 3 were unable to discriminate. The 17 patients who responded to levodopa reported complete relief.