The Effectiveness and Safety of Risperidone on Bipolar Disorders

Bipolar disorders affect about 1-2.5% of the population. They are leading causes of disability and associated with significant health care costs. Antipsychotic medicaitons have a long history of use in bipolar disorders, for example, chlorpromazine has been used since early 1950s. Typical antipsychotics are effective against mania, but it has some risks such as inducing depression, tardive dyskinesia. But atypical antipsychotics are effective in the management of acute manic symptoms with a far lower risk of extrapyramidal side effects than typcial antipsychotics. So there is a trend to choose atypical antipsychotics in the treatment of bipolar disorders in clinical practice. Risperidone is a serotonin-dopamine antagonist which was approved by FDA in 1994 and introduced into Korea in 1996. Risperidone appeared effective in controlling manic symptoms but also to have risks for inducing manic symptoms. Recent double-blind studies showed risperidone to be effective for acute mania, both as monotherapy and in combination with mood stabilizers. We reveiw retrospective chart reveiws, open label studies and doubleblind studies published in Korea and other countries to investigate the efficacy and tolerability of risperidone in bipolar and schizoaffective disorders. Mounting evidence supports its efficacy, low incidence of extrapyramidal side effects and tardive dyskinesia in acute bipolar disorders. But further studies are needed to conclude whether risperidone is effective in the longterm treatment. With the advance of psychopharmacolgy, psychiatrists can have hope in treating bipolar patients.