Risperidone in the treatment of first episode psychosis

To evaluate the efficacy and safety of risperidone in Singapore patients with first-episode psychosis in an eight-week open label prospective study.

Previously untreated male and female patients aged 18 - 65 with DSM IV schizophreniform disorder or DSM IV schizophrenia for no longer than 12 months were recruited from Woodbridge Hospital and Geylang Psychiatric Outpatient Clinic. Patients were treated with risperidone for 56 days. Outcome was assessed with the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impression scale (CGI). Safety was assessed by monitoring of vital signs and by comparing the frequency of adverse events (AEs) before and after treatment.

24 patients with a mean age of 33.29+/-9.12 years and a mean duration of illness of 166.5+/-111.4 days (median 180 days) were included. The mean risperidone dosage was 2.7 mg +/- 1.0 at day 56. Mean PANSS total scores reduced by 50.21% from 88.29+/-21.55 at baseline to 43.96+/-7.5 at endpoint (p < 0.001). The responder rate (> or = 20% reduction in the total PANSS score) was 87.5%. 13 patients (54.2%) exhibited a 50% or greater reduction in total PANSS score. Except for item G5 (mannerisms and posturing) all single PANSS items were reduced significantly. The CGI scores of all patients improved at endpoint. No serious adverse events were reported.

Overall the therapy of first-episode psychosis patients with risperidone was effective and safe.