The effect of l-dopa on young patients with simple schizophrenia, treated with neuroleptic drugs

Abstract

Thirteen out of 18 young out-patients with simple schizophrenia under neuroleptic treatment completed a double-blind cross-over trial with Madopar® [l-Dopa + benserazid (a peripheral decarboxylase inhibitor)] and placebo. Nine patients were given 900 mg l-Dopa + 225 mg benserazid daily, 1 patient received 600 mg l-Dopa + 150 mg benserazid, and 3 patients, 300 mg l-Dopa + 75 mg benserazid. In these doses, l-Dopa was effective against emotional withdrawal, blunted affect, tendency to isolation and apathy, without inducing or aggravating productive, accessory symptoms. The activity score, according to the specific activity-withdrawal scale, was significantly increased (P<0.05), whereas the total BPRS score (Brief Psychiatric Rating Scale) was slightly, but significantly reduced (P<0.05). In cases where l-Dopa had to be limited to 600 and 300 mg daily, a tendency to anxiety, distortion of thinking, and a sense of unreality were observed, depending on the dose of l-Dopa. In no case were gastrointestinal, cardiovascular or neurological sideeffects observed.