The sleep of 13 chronic male schizophrenics was studied during a one-month trial of chlorpromazine and compared with one-month placebo periods. Electroencephalographic recordings were made only after the patients had been on chlorpromazine hydrochloride or a placebo for at least three weeks.
Sleep latency and awake time were significantly decreased on chlorpromazine while stage II, delta sleep, delta%, nonrapid eye movement (NREM) sleep, REM activity, REM latency, and REM density were significantly increased. There were no significant changes in REM time, REM%, stage II%, and NREM%.
Kaplan J, Dawson S, Vaughan T, Green R, Wyatt RJ. Effect of Prolonged Chlorpromazine Administration on the Sleep of Chronic Schizophrenics. Arch Gen Psychiatry. 1974;31(1):62-66. doi:10.1001/archpsyc.1974.01760130044007