The Effect of Risperidone on Cognitive Symptoms of Schizophrenia: A Comparison with Haloperidol

Background and Several studies have demonstrated, that atypical antipsychotics attenuate cognitive symptoms of schizophrenia more than first generation of antipsychotics. Because there was no comprehensive and reliable study on evaluating these effects in Iranian population, the research group decided to compare the effects of haloperidol and risperidone, both Iranian drug laboratorie's products, on the cognitive symptoms of patients with schizophrenia. 66 patients with the diagnosis of schizophrenia, according to DSM-IVTR criteria, who were hospitalized in Razi's Psychiatric Center, Tehran, were included in the study. After 2 weeks of wash-out period, patients were randomized in two groups, treated with haloperidol and risperidone, and in 8 week period basic and weekly MMSE were performed for all. Both drugs improved cognitive symptoms of patients, and the course of improvement started in the 2nd week of treatment with no significant statistical difference. The study didnt confirm the preferentiality of risperidone vs. haloperidol on the cognitive symptoms of schizophrenia, which was demonstrated in western articles. Therefore, choosing each drug for treating patients must fulfill on other goals, such as the profile of their side effects.