Seventy-six male and female Negro chronic schizophrenics were assigned randomly to either diphenylhydantoin or a placebo after discontinuing phenothiazines.
During an eight-week treatment course, the dosage of diphenylhydantoin was gradually increased from 325 to 625 mg/day, for most patients. Measures used were the Brief Psychiatric Rating Scale (BPRS), the Nurses Observation Scale for Inpatient Evaluation, and the Crownsville Psychiatric Scale (parts I and II). Statistical analyses were done at four and eight weeks.
Patients on both diphenylhydantoin and the placebo deteriorated on most measures. Differences in favor of diphenylhydantoin were found for the BPRS variables, Hostility, and Thought Content. Optimal dosage of diphenylhydantoin appeared to be under 500 mg, daily, since retardation and blunted affect were more predominant with diphenylhydantoin at the highest dose levels. Indications were that men with high initial disorder scores, especially for hostility, responded best to diphenylhydantoin.
Simopoulos AM, Pinto A, Uhlenhuth EH, McGee JJ, DeRosa ER. Diphenylhydantoin Effectiveness in the Treatment of Chronic SchizophrenicsA Double-Blind Controlled Study With a Placebo. Arch Gen Psychiatry. 1974;30(1):106-111. doi:10.1001/archpsyc.1974.01760070084013