Extrapyramidal signs and clinical symptoms in first-episode schizophrenia: response to low-dose risperidone

The purpose of this study was to determine the prevalence of extrapyramidal signs or symptoms (EPS) and clinical symptoms in first-episode schizophrenia, before any treatment, during and after treatment with a novel antipsychotic, risperidone. Twenty-two (17 men; 5 women) patients were examined using the Extrapyramidal Symptom Rating Scale, Positive and Negative Syndrome Scale (PANSS), Clinical Global Impressions-Severity of Illness and Improvement, and Global Assessment of Functioning. Three patients (14%) had distinct EPS at baseline, whereas all were free of EPS after treatment with risperidone. On the maximum dose of risperidone (5-8 mg), 32% of the total sample developed mild akathisia or parkinsonism, both of which diminished with dosage reduction. No clinically significant EPS were observed in patients receiving 2 to 4 mg of risperidone. Analysis of symptom response of the lower (2-4 mg) versus the higher (5-8 mg) doses of risperidone resulted in superior outcome in the 2- to 4-mg group for all three symptom clusters of the PANSS. In addition, 91% of the low-dose group achieved a 20% or greater reduction in total PANSS score compared with 27% for the high-dose group. These findings have clinical relevance directed at the early and longer-term treatment of schizophrenia.