The Use of N-acetylcysteine Supplementation to Decrease Irritability in Four Youths With Autism Spectrum Disorders

Children and adolescents with autism spectrum disorder (ASD) often experience high levels of irritability, which adversely affects their functioning and behaviors. N-acetylcysteine (NAC), an antioxidant precursor to glutathione, has recently been studied for a variety of neuropsychiatric disorders. There is growing evidence to support its use to decrease irritability and self-injurious behaviors in youth with ASD. However, previous studies were limited to outpatient youth with mild symptoms of irritability, maintained on stable medication regimens, who do not meet criteria for higher levels of care. We describe the use of NAC among 4 youths (14-17 years) with ASD who had Aberrant Behavior Checklist-Irritability (ABC-I) scores of ≥ 20 and other psychotropic medication trials prior to treatment with NAC. In all of the cases, NAC appeared to be well tolerated. There was a reduction of symptoms of irritability and/or antipsychotic medication dosages in these cases; despite this, the authors cannot know whether use of NAC or other medication or behavioral strategies were responsible for such changes because this study was not a controlled trial.