Risperidone: the Korean Experience in the Treatment of Patients with Schizophrenic Disorder

Yoon, Jin Sang; Bae, Kyung Lyul

Abstract

Since the introduction in 1996 of the novel antipsychotic risperidone in Korea, clinical experiences with this agent for the treatment of schizophrenia have been accumulated. This article attempts to review the published literature on clinical effects of risperidone in Korean patients with schizophrenic disorder. All available clinical articles by Korean authors or involving Korean patients were searched through electronic databases (KISEP and KMBASE) or manually. Retrieved articles were primarily written in Korean and were of several types (original article, case report, review and tutorial), and addressed various issues:efficacy, safety and tolerance, quality of life and subjective well-being, pharmacoeconomics, optimal dose and titration rate, etc. The main results are as follows. Many clinical trials to date have shown that risperidone is an effective antipsychotic agent in the treatment of positive and negative symptoms, with a milder side effect profile, in particular much less EPS than haloperidol. The effects were favorable even in chronic or treatment-resistent patients. It appears to have additional effects on quality of life and subjective well-being. Preliminary evidence suggested that risperidone may improve some types of cognitive function. Weight gain was a major problem although the weight increase was less severe than that seen with clozapine and olanzapine. Some experimental studies demonstrated prolactin elevation in patients treated with risperidone;however, clinical significance of hyperprolactinemia was unclear. Various specific cases of adverse events were reported during risperidone therapy, including new onset of manic symptoms, neuroleptic malignant syndrome, stuttering, premature ventricular contraction and hepatotoxicity;however, the numbers of cases were very few, the causal relationship was not clear in some cases, and there were no fatalities or life threatening events. At present the medication costs for risperidone are much greater than those for conventional drugs. However, risperidone therapy may be associated with substantial cost benefits, when total health service costs and quality of life were taken together into account. The target dose found to be effective was lower than the originally proposed target dose of 6 mg/day. A slower titration was also found to be preferable. Taken together, in spite of lacking in randomized controlled clinical trials and long term studies, Korean literature on risperidone use for schizophrenia provides valuable information to clinicans regarding the effective use of risperidone. Risperidone should be a first line drug for the treatment of Korean patients with schizophrenic disorder.