Assessment the Efficacy of Atomoxetine in Autism Spectrum Disorders: A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Autism spectrum disorders (ASD) are early onset conditions characterized by significant impairment in social interaction and communication. Objectives: The purpose of this study was the assessment of Atomoxetine effectiveness and tolerability in the treatment of autistic features in patients with ASD. Methods: A total of 44 children, aged 6 to 17 years, diagnosed with ASD, enrolled in a 8 week randomized clinical trial. The study conducted at the outpatient clinic of Ibne-sina hospital and Dr. Sheikh hospital affiliated to the Mashhad Medical University in Iran, between August 2015 to September 2016. Subjects were randomly allocated to Atomoxetine (0.5 to 1.2 mg/kg/day) plus risperidone or Placebo plus risperidone. The primary outcome was assessed by the childhood autism rating scale (CARS) and clinical global impression (CGI). Patients were evaluated at baseline, 4 weeks and 8 weeks after the administration of the drug. Mixed ANOVA test is used for the outcome of evaluation. The clinical trial registration number is: IRCT2016022826802N1. Results: Atomoxetine augmentation comparison to placebo augmentation showed significant improvement in global impression and severity index in CGI, and also in total score of CARS and 7 subscales of CARS including relationship to people, emotional response, body use, listening response, fear and nervousness, nonverbal communication, and activity level (all P value 0.05). The most common adverse effects of Atomoxetine were mood change, irritability, and GI disturbance. Conclusions: The results showed that Atomoxetine add-on therapy may be effective in symptoms of ASD while adverse effects tend to subside. The authors suggest further studies for clarifying this conclusion.