Effect of aripiprazole on the hyperprolactinmia induced by risperidone in male schizophrenia patients

Objective To investigate the efficacy and safety of aripiprazole on the hyperprolactinmia induced by risperidone in the first-episode patients with male schizophrenia.Methotis All 80 first-episode male inpatients who had received no antipsychotic medication were randomly assigned to research group(n=40)and control group(n=40).All the patients were treated with risperidone for 4 weeks.and then patients whose prolactin level reached to 60μg/L were administered additionaJ aripiprazole 5 mg daily or placebo for 12 weeks.The plasma prolactin(PRL)level was measured at weeks 0,4,8,12,and the Positive and Negative Syndrome Scale(PANSS)and Treatment Emergent Symptom Scale(TESS)were assessed.Results Plasma prolactin levels were significantly reduced at the end of the study compared with the 4th weekend[(25±7)μg/L vs.(76±17)μg/L]in research group(t=15.87;P＜0.01),while there were no significant difference between the 4th weekend and post treatment in control group[ (78±15)μg/L vs.(79±13)μg/L](t=0.72;P＞0.05).At week 12,the decline rate and the normal ratio of plasma prolactin levels were significantly higher in aripiprazole group[(66±11)%,67.6%]than that in control group[(-1±18)%,6.5%](both P＜0.01).Compared with the baseline,the PANSS score showed significant reduction in both groups at the end of the study [(38.29±5.67)vs.(83.68 ±12.56)],[(39.71±7.80)vs.(83.81±13.47)](both P＜0.01),and there were no significant differences on the PANSS score between both groups(P＞0.05).The incidence of side effects showed no significant difference between aripiprazole and control group(P＞0.05).Conclusion The results indicate that aripiprazole may be effective and safe for the treatment of male schizophrenics with risperidone induced hyperprolactinemia. Key words: Schizophrenia;  Hyperprolactinmia;  Risperidone;  Aripiprazole