Journal of Childhood and Adolescent Psychopharmacology, Arnold et al
The National Institute of Mental Health (NIMH) Research Units on Pediatric Psychopharmacology (RUPP) Autism Network found an effect size of d = 1.2 in favor of risperidone on the main outcome measure in an 8-week double-blind, placebo-controlled trial for irritability in autistic disorder. This paper explores moderators and mediators of this effect. This study found the benefit-risk ratio of risperidone is better with greater symptom severity. Risperidone can be individually titrated to optimal dosage for excellent response in the majority of children. Weight gain is not necessary for risperidone benefit and may even detract from it. Socioeconomic advantage, low prolactin, and absence of co-morbid problems nonspecifically predict better outcome. Mineral interactions with risperidone deserve further study.