Low urinary dopamine and prediction of phenothiazine-induced Parkinsonism: a preliminary report

Psychiatric patients who excreted larger amounts of urinary free dopamine before treatment were significantly more likely than patients excreting smaller amounts to develop parkinsonian side effects during moderate-dose trifluoperazine therapy. If this finding is replicated, urinary free dopamine determinations could prove valuable in indicating which patients should receive those antipsychotic drugs least likely to produce extrapyramidal side effects.