Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.


Autistic spectrum disorder (ASD) refers to a syndrome associated with persistent impairments in communication skills, social interactions, and so forth. Given the approval of risperidone and naltrexone by U.S. Food and Drug Administration (FDA) for ASD cases and extant controversy concerning their pertained side effects, this double-blind, placebo-controlled, crossover clinical trial with 2-treatment, 2-sequence, 2-period design was intended to evaluate the behavioral effectiveness of individual risperidone and its combination with naltrexone in autistic children aged 4-12 years old.
Materials and Methods
A total of30 autistic children were recruited in this study, and then equally assigned into groups A and B. The first group underwent co-treatment with risperidone and naltrexone, while group B was instructed to use placebo and risperidone for 8 weeks. After a washout period of two weeks, treatments were crossed over for another 8 weeks. The behavioral changes were assessed applying the childhood autism rating scale (CARS).
There were five out of 30 cases at the risk of drop-out due to side effect in group A, while only three failed to complete the trial in group B. The effect size of the combined treatment was greater than the individual which was manifest in the total score of CARS, improved 4-week listening response, and 8-week general impressions.
According to the results, naltrexone can be a promising candidate for the management of behavioral symptoms in autism children.