Psychotropic prescription practices in east Asia: looking back and peering ahead

The present review focuses on the pharmacoepidemiological issues of psychotropic drug use in countries within east Asia, with special emphasis on antipsychotic, antidepressant and benzodiazepine prescriptions. Pharmacogenetic studies in different ethnic groups are also reviewed.

Recent studies have revealed the prevalence of antipsychotic polytherapy (defined as the use of more than one antipsychotic; up to 45.7%), less conservative antipsychotic use (defined as the use of more than 1000 mg/day chlorpromazine equivalents; up to 17.9%) and depot antipsychotic use (up to 15.3%) in different populations in east Asia. Clozapine is commonly prescribed (up to 60%) in China. There is a trend of increasing second-generation antipsychotic use in east Asian countries. Up to 67.5% of patients received newer antidepressants such as selective serotonin reuptake inhibitors. Benzodiazepine medications are used in up to 29.9% of study populations. Socioeconomic factors appear to be one of the major common factors that affect the prescription of antipsychotics and newer antidepressants. Pharmacogenetic factors associated with antipsychotic response, weight gain and extrapyramidal side effects have been examined. Treatment adherence and pharmacoeconomic factors are relatively understudied.

Future studies on prescribing trends of antipsychotics and antidepressants need to focus on children, adolescent and elderly patient populations, the impact of changing prescription trends and the long-term effects on patients and their caregivers, as well as pharmacogenetic factors, which can potentially pave the way for better and more individualized prescription of psychotropic drugs in east Asia.