A study of the efficacy and safety of switching from oral risperidone to risperidone long-acting injection in older patients with schizophrenia

Abstract

We investigated the clinical efficacy and safety of switching to risperidone long-acting injection (RLAI) in older patients with schizophrenia receiving oral risperidone. The subjects were 48 inpatients who had been diagnosed with schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition. Their clinical symptoms were assessed using the Positive and Negative Syndrome Scale and the Clinical Global Impression - Severity of Illness scale, and their safety was assessed using the Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS), body weight, body mass index, and blood biochemistry tests. No significant differences in clinical symptom improvement efficacy were seen between the group switched to RLAI and the control group. The mean changes from baseline on the DIEPSS total score and prolactin level were significantly greater in the older group switched to RLAI than in the control group. Furthermore, in older patients, RLAI allowed the dosage of the concomitant medication to be significantly reduced compared with the control group. The results of this study suggest that switching older patients from oral risperidone to RLAI may result in superior efficacy and safety, and may also make it possible to reduce the dosage of the concomitant medication.