Mental patients are at more risk of being under polypharmacy in compare to other medical disorders. Elderly patients are more at risk of using polypharmacy.

This research was designed to observe the benefits of replacing polypharmacy with a single medication in elderly patients with chronic schizophrenia.

Antipsychotic polypharmacy in elderly results in higher rate of interactions, side effects and cost. Polypharmacy would escalate medical risks which ends to decrease patients' quality of life.

A survey was performed at the long stay public and academic Tehran Razi Mental Hospital. From the initial 157 conveniently access patients, 59 cases were selected based on inclusion and exclusion criteria. Before intervention, 7 patients did not participate in the study due to their newly occurred medical conditions. 52 cases entered and completed the 36 weeks of research time period. Systematically, the patients' multiple antipsychotics were switched to a single medication, Risperidone. Their clinical assessments applied weekly for 36 weeks. Evaluations achieved by using validated and reliable tools of Brief Psychotic Rating Scale (BPRS), Global Assessment of Functions (GAF) and Extra-Pyramidal Syndrome (EPS) tools.

Wilcoxon signed ranks test and Friedman test revealed a significant difference in post intervention for positive, negative and general schizophrenic symptoms. Functional improvements and lower incidence of EPS, showed a significant difference statistically.

Risperidone may be safety used instead of other multiple antipsychotics in elderly patients with typical chronic schizophrenia. This replacement possibly will result in more clinical benefits, obvious cost reduction and less side effects.