OBJECTIVES: Long-term pharmacologic treatment of schizophrenia is critical towards optimizing outcome. The objective of this study is to estimate the cost-effectiveness of paliperidone ER in the long-term treatment of schizophrenia compared to other oral atypical antipsychotic drugs (risperidone, olanzapine, quetiapine, ziprasidone and aripiprazole) in Turkish setting.METHODS:Model: An existing decision analytic model is adapted (based on literature and expert panels). The time horizon is one year. The study is performed from the health care payer perspective.Patient group: Community dwelling patients with schizophrenia who have suffered an acute exacerbation.Data sources: The clinical data are acquired from the literature. Resource use data are derived via expert panel. Prices of medications, institutional discount rates and other costs related to the treatment are obtained from Ministry of Health Drug Price List, Price List of Social Security Institution Health Implementation Guideline Appendix 2/D, 8 and 9, respectively.Clinical and economic outcomes: The clinical outcome measures are the proportion of patients relapsing, number of stable days and number of functional stable days. Only direct medical costs, i.e. costs of antipsychotics, treatment of side effects, physician visits, hospitalization and laboratory examinations are considered.RESULTS:Clinical and economic results are as follows: Total costs: €1959, €1852, €1903, €2396, €2627, €2630; number of relapses: 1.80, 2.03, 1.84, 2.14, 2.26, 2.22; number of stable days: 223, 207, 219, 198, 186, 188; number functional stable days: 152, 142, 146, 112, 106, 113 for paliperidone, risperidone, olanzapine, quetiapine, ziprasidone and aripiprazole, respectively. ICER values are of 6.85€/stable day; €10.03/functional stable day; €478.70/prevented relapse for paliperidone. One-way sensitivity analyses prove that results of the study are strong.CONCLUSIONS:In the long-term treatment of schizophrenia, paliperidone is the dominant therapy in comparison to quetiapine, ziprasidone and aripiprazole. Compared to risperidone and olanzapine, it is the cost-effective therapy option.