Risperidone in autism.

Long-term effects of risperidone in children with autism spectrum disorders: a placebo discontinuation study.


Source
Journal of the American Academy of Child & Adolescent Psychiatry. 44(11):1137-44, 2005 Nov.

OBJECTIVE:

The short-term benefit of risperidone in ameliorating severe disruptive behavior in pediatric patients with autism spectrum disorders is well established; however, only one placebo-controlled, long-term study of efficacy is available.

CONCLUSIONS:

This study indicates the effectiveness of risperidone during a period of several months, reducing disruptive behavior in about half of the children with autism spectrum disorders. The results provide a rationale for the continuing use of risperidone beyond 6 months, although considerable weight gain can limit the use of this agent.

Clinical Implications:

The present study indicates the long-term effectiveness of risperidone in low to intermediate doses with regard to reducing severe disruptive behavior problems, not only in children with typical autism but also in children well beyond the classic phenotype of autism into the broader spectrum. To ensure enduring treatment effects, a modest increase in dose after the first months of treatment may be required. Positive long-term responses are to be expected in about half of the children. Benefits may also be achieved in hyperactivity, repetitive behavior, and social functioning. Weight gain is the most worrying side effect. Although the relapse rate was 2.6-fold higher in the placebo group, 33% of the patients on placebo remained stable. This may point either to a placebo effect in the initial phase, improvement caused by factors other than medication, or a stabilizing effect of risperidone even after discontinuation, suggesting that some long-term responders can safely be withdrawn from risperidone.