Withdrawal of Long-Term Phenothiazines from Chronically Hospitalized Psychiatric Patients

Abstract

A study was conducted of the effect of substituting placebo medication for active phenothiazine medication under double-blind conditions, in a population of chronically hospitalized psychotic patients who had all been undergoing long-term phenothiazine treatment. Behavioural change was assessed monthly by psychiatric nurses using a ward behaviour inventory, which had been specially constructed to be sensitive to kinds of behaviour likely to affect the clinical prescription of phenothiazines. At the fifth month of the study, differences were noted between the placebo-substituted group and a control group continuing to receive their originally-prescribed phenothiazine compounds. Significant worsening in the Placebo group did not appear until the fifth monthly rating, and at that time significant improvement in the control (medication unchanged) group also first became evident. These results support the hypothesis that the continued long-term use of phenothiazine compounds in chronically-hospitalized psychotics is effective in the sustained reduction of psychopathological behaviour. An investigation of trifluoperazine and chlorprothixene within the same double-blind design indicated that both were significantly more effective than placebo in maintaining the behavioural level typical of the prior long-term medication with phenothiazines. Using the FPN test as one measure of the time course of urinary excretion of some of the phenothiazine metabolites, no relationship was demonstrated in the placebo-substituted group between FPN changes and behavioural worsening. The FPN test, rated blind, was able to discriminate the placebo-substituted group from the group continuing to receive their usual phenothiazines; as a single measure of the time course of urinary excretion of phenothiazine metabolites, however, FPN changes were not related to behavioural worsening within the placebo-substituted group.