Fifty-two psychiatric patients and 4 with severe insomnia only received propiomazine orally as a hypnotic. 1. Forty milligrams proved the most satisfactory dose; smaller amounts were relatively ineffective; larger doses did not increase the hypnotic response. 2. Seventy-seven percent exhibited a good to excellent result. 3. No toxic effects or severe side reactions were observed. Propiomazine is an effective hypnotic, comparable to the new synthetic sedative agents. Further studies are recommended.