A controlled trial of phenothiazine withdrawal in chronic schizophrenic patients.

Phenothiazine drugs were withdrawn from 17 chronic schizophrenic in-patients, with a control group of 14 patients remaining on active medication. The trial was conducted under double blind conditions over a period of 42 weeks with weekly assessment of the patients by ward nurses. Of the placebo group 35% relapsed, relapse being related to the level of previous active medication.