The rising prevalence of autism spectrum disorder (ASD) has increased the need for evidence-based treatments to lessen the impact of symptoms. Presently, no therapies are available to effectively treat individuals with all of the symptoms of this disorder. It has been suggested that hyperbaric oxygen therapy may alleviate the biochemical dysfunction and clinical symptoms of ASD. To determine whether treatment with hyperbaric oxygen:1. improves core symptoms of ASD, including social communication problems and stereotypical and repetitive behaviors;2. improves noncore symptoms of ASD, such as challenging behaviors;3. improves comorbid states, such as depression and anxiety; and4. causes adverse effects. On 10 December 2015, we searched CENTRAL, Ovid MEDLINE, Embase, and 15 other databases, four of which were Chinese language databases. We also searched multiple trial and research registers. We selected randomized controlled trials (RCTs) and quasi-RCTs of any dose, duration, and frequency for hyperbaric oxygen therapy compared with no treatment or sham treatment for children and adults with ASD.

Xiong, Chen, Luo, Mu (2016). Hyperbaric oxygen therapy for people with autism spectrum disorder (ASD). The Cochrane database of systematic reviews, 2016 Oct;10():CD010922. https://www.ncbi.nlm.nih.gov/pubmed/27737490