Risperidone in the treatment of first-episode psychotic patients: a double-blind multicenter study

An international, multicenter, double-blind study was conducted in 183 patients with a first psychotic episode (provisional schizophreniform disorder or schizophre-nia; DSM-III-R) treated with flexible doses of risperi-done or haloperidol for 6 weeks. At endpoint, 63 per-cent of risperidone-treated patients and 56 percent of haloperidol-treated patients were clinically improved (a 50 % reduction in Positive and Negative Syndrome Scale total scores). Risperidone was better tolerated than haloperidol: the severity of extrapyramidal symptoms was significantly lower in the risperidone-treated patients; significantly fewer risperidone-treated patients required antiparkinsonian medica-tion; and significantly fewer discontinued treatment because of adverse events. A post hoc analysis revealed that low doses of these antipsychotics were efficacious in some patients. Furthermore, the severity of extrapyramidal symptoms and the use of anti-parkinsonian medications were significantly lower in patients receiving low doses (maximum, s 6 mg/day) than high doses (maximum,> 6 mg/day) of risperidone or haloperidol. These findings are consistent with the suggestion that patients with a first psychotic episode may require low doses of antipsychotic medications. Studies designed specifically to compare low and high doses of antipsychotics are warranted to help optimize treatment for these patients