A quarterly publication of the Autism Research Institute

The Autism Research Review International is quarterly publication of the Autism Research Institute

Fall, 2020 | Number 4, Volume 34

NAC supplementation may improve some symptoms

A recent meta-analysis of five studies suggests that supplementation with N-acetylcysteine (NAC)—the supplement form of the amino acid cysteine—may improve some symptoms in individuals with autism spectrum disorders (ASD). 

Pooling results from four of the studies, Tsung-Min Lee and colleagues found that NAC supplementation for 8 to 12 weeks resulted in improvements in total score on the Aberrant Behavior Checklist. Pooled results from three trials showed significant improvements in hyperactivity and irritability, and pooled results from two trials showed improvements in social awareness. 

The researchers conclude that “NAC is safe and tolerable, reduces hyperactivity and irritability, and enhances social awareness in children with ASD.” 

The researchers believe NAC benefits individuals with autism by helping to correct abnormalities of the glutaminergic system, which are implicated in autism.


“Effectiveness of N-acetylcysteine in autism spectrum disorders: a meta-analysis of randomized controlled trials,” Tsung-Min Lee, Kuan-Min Lee, Chuan-Ya Lee, Hsin-Chien Lee, Ka-Wai Tam, and Wui Loh, Australian and New Zealand Journal of Psychiatry, September 8, 2020 (online). Address: El-Wui Loh, Center for Evidence-Based Health Care and Shared Decision Making Resource Center, Department of Medical Research, Taipei Medical University Shuang Ho Hospital, No. 291, Zhongzheng Rd., Zhonghe District, New Taipei City 23561, Taiwan, [email protected].