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

Since its introduction in Korea of risperidone in 1996, a great deal of clinical experience in treatment of schizophrenia has been accumulated with this early atypical antipsychotic medication in Korea. This article will review the published literature on the clinical efficacy in Korean patients with schizophrenia. All published journal articles in Korea have been searched from the electronic databases (KISEP and KMBASE) as well as manually. The articles reviewed were primarily written in Korean and included original research papers, case reports, review articles, and lecture papers. In addition to the clinical efficacy, the reviewed papers also addressed the safety and tolerance, quality of life and subjective well-being, pharmacoeconomics, and optimal dosing and titration rate. The reviewed papers found that risperidone is an effective antipsychotic agent in treatment of both positive and negative psychotic syndromes in schizophrenia and possesses milder side effect profiles, inducing especially the EPS. Furthermore, its clinical efficacy was favorable even in patients with chronic treatment-resistant schizophrenia. In addition, it appears to have effects on the quality of life and subjective well-being. Preliminary evidence also suggests that risperidone may have positive effects on cognitive functioning. Weight gain problem was less common than the clozapine and olanzapine. A few studies demonstrated prolactin elevation in patients treated with risperidone; however, the clinical significance of hyperprolactinemia was unclear. Other adverse effects with risperidone include new onset of manic symptoms, neuroleptic malignant syndrome, stuttering, premature ventricular contraction and hepatotoxicity. However, these events were few in number. The causal relationship was not clear in some cases and there were no fatalities or life threatening events. At present the cost for risperidone treatment is much higher than that of the conventional antipsychotic treatment. However, risperidone therapy may be associated with the substantial cost benefits, when the total health service costs and quality of life were taken into account. The clinically effective dosage in Korean patients was found to be lower than the previously proposed target dose of 6mg/day. A slower titration was also found to be preferable. In summary, in spite of a lack of randomized controlled clinical trials and long term studies, the Korean experience of risperidone use in schizophrenia provides valuable population specific clinical information to clinicians. We recommend that risperidone should be the first line drug for the treatment of Korean patients with schizophrenic disorder.