An open-label trial of risperidone in children with autism

Abstract

Background: Risperidone has potent effects on serotonin and dopamine neuronal systems, both of which have been implicated in the pathophysiology of autism. Risperidone is increasingly being used to treat specific symptoms in children with autism. Objective: The purpose of this study was to investigate the efficacy and tolerability of risperidone in young children with autism. Methods: In this single-site, 6-month, open-label study, young autistic children aged 3 to 7.5 years were administered risperidone 0.5 mg/d for 15 days and then 1 mg/d until 3 months; doses were thereafter individually adjusted to a maximum of 2 mg/d between the third and sixth month. The Clinical Global Impression—Severity of Illness (CGI-SI) scale, Childhood Autism Rating Scale (CARS), and Abnormal Involuntary Movement Scale (AIMS) were used to assess efficacy. The CGI-Adverse Effect scale and the Adverse Effect Checklist were used to assess the incidence and severity of adverse events. Results: A total of 20 children (mean age, 4.95 ± 1.18; range, 3–7.5 years) were enrolled; 16 completed the 6-month study. Two children were withdrawn due to noncompliance with the treatment protocol during the first month, and 2 children were withdrawn from the study during the first month because of marked agitation, anger, and aggression thought to be related to treatment. The mean dose of risperidone was 1.53 mg/d (range, 0.04–0.11 mg/kg per day). Thirteen of the 16 children (81%) demonstrated at least 1 grade improvement on CGI-SI scores. Mean total CARS score significantly decreased from 39.06 ± 6.23 to 32.03 ± 8.73 after 6 months ( P = 0.001). Scores on 11 of the 15 subscales of the CARS showed significant improvement ( P < 0.05). Four subjects experienced mild sedation, and 2 experienced weight gain of <10%. One child with mild sedation also experienced slight akathisia. Conclusion: In this population of young autistic children, risperidone had positive effects on most symptoms of autistic disorder. Additional double-blind, placebo-controlled studies are needed to determine the effectiveness of risperidone in the management of autism.