Efficacy and safety of different fixed dose of risperidone in treatment of first-episode schizophrenia

Objective The purpose of this study was to explore the optimum dosage of risperidone in treatment of first-episode schizophrenia. Methods All 126 first-episode patients with schizophrenia diagnosed according to CCMD-3 criteria were randomly assigned to being treated with fixed daily doses of 2 mg,3 mg,4 mg or 5 mg of risperidone. The symptoms were assessed with the Positive and Negative Symptom Scale (PANSS) and Clinical Global Impression at baseline and at the 1st,2nd,4th,6th,8th,and 12th weekend,and the side effects assessed with the Treatment Emergent Symptom Scale and the Extrapyramidal Symptom. Results Altogether 120 patients finished the study. After 12-week treatment,there were no significant differences among the different dosage group according to the PANSS total score. The negative symptom score was significant lower in the 2 mg/d group compared with other three groups. There was no significant difference of the response rates among all groups. The EPS was most common side effect,which was milder in 2 mg and 3 mg groups than in other groups. Conclusions It is recommended that the risperidone dose of 3 mg/d is optimum in treatment of first-episode schizophrenia for the definite efficacy with milder side effect.