Implications of phenothiazine side effects: a study of antiparkinsonian agents in an older population.

A study of anti-Parkinsonism agents in prolonged phenothiazine therapy seeks to clarify some anecdotal misconceptions. Antiparkinsonian agents do not appear to affect the therapeutic efficiency of phenothiazines, nor does using them on a "demand" basis increase the problems of control of parkinsonian side effects. Older patients, however, appear to require the extended usage of antiparkinsonian agents rather more than some studies would suggest. Sustained release antiparkinsonian agents may yet further simplify the management of schizophrenia.