Hyperbaric Oxygen Therapy and Autism: Reviewing the Research

Important: Hyperbaric oxygen therapy is not FDA-approved for autism spectrum disorder. This is an investigational use. Evidence is preliminary. Insurance will not cover HBOT for this condition. All costs are out-of-pocket.

Parents of autistic children often research every option available. That’s not surprising. HBOT has been marketed to the autism community for years, and the claims are sometimes dramatic. The research tells a more complicated story.

Why Parents Are Researching HBOT for Autism

Autism spectrum disorder (ASD) affects communication, behavior, and social interaction. It’s a developmental condition, not a disease with a single, reversible cause. Families often face long waiting lists for evidence-based therapies and encounter many alternative treatments along the way.

HBOT has been part of that alternative treatment space for over a decade. The theoretical rationale focuses on two areas: neuroinflammation and cerebral blood flow. Some research suggests both may be factors in certain autism cases, and HBOT is hypothesized to address both through increased oxygen delivery and anti-inflammatory effects.

The hypothesis is plausible enough to have attracted researchers. Whether the hypothesis holds up in clinical trials is a different question.

What the Research Has Found

The most-cited study is Rossignol et al. (2009), a randomized controlled trial of 62 children with autism. The trial compared HBOT to a lower-pressure control condition. It found modest improvements in some behavioral measures in the HBOT group. It was published in BMC Pediatrics.

But the study has drawn criticism. Methodological concerns include the use of a slightly pressurized control condition rather than a true placebo, and effect sizes were small. The study hasn’t been replicated in a larger, more rigorous trial.

The more important reference is the Cochrane systematic review. Brignell et al. updated the review in 2019 and 2020. The conclusion from the Cochrane review (PMID: 32400879): current evidence is insufficient to determine whether HBOT is safe and effective for autism spectrum disorder.

Cochrane reviews are considered the gold standard in evidence synthesis. They pool available studies, assess their quality, and report what the overall body of evidence shows. The conclusion here is clear. The evidence isn’t there to support HBOT as a treatment for autism.

What Major Organizations Say

The American Academy of Pediatrics does not endorse HBOT for autism.

The Interagency Autism Coordinating Committee (IACC), which advises the U.S. Department of Health and Human Services on autism research, does not list HBOT as an evidence-based intervention.

The Undersea and Hyperbaric Medical Society (UHMS), the main professional body for hyperbaric medicine, does not include autism among its approved indications.

None of these organizations say HBOT definitely doesn’t work. They say the evidence isn’t strong enough to recommend it. That’s the honest position the research supports.

Risks of Unproven Treatments

HBOT isn’t without risk. Side effects include ear pain and pressure from changing pressures, sinus discomfort, and temporary nearsightedness. Oxygen toxicity, while rare, is a real possibility, particularly at higher pressures.

For a child who may not be able to reliably communicate discomfort, these risks need careful management. An experienced provider who works with children is important if a family decides to pursue HBOT despite the evidence limitations.

The financial cost is also real. Insurance won’t cover this. Sessions run $250-450 each. A typical trial course involves 40 sessions or more. That’s $10,000 or more out-of-pocket with no guarantee of benefit.

Be cautious of clinics that market HBOT to autism families with specific outcome promises. When the underlying evidence base is weak, confident marketing claims are a warning sign, not a reassurance.

Frequently Asked Questions

Are there evidence-based therapies for autism that have stronger research support? Yes. Applied behavior analysis (ABA), speech-language therapy, and occupational therapy all have more robust evidence bases than HBOT for autism. Your child’s care team can help evaluate what’s appropriate for your child’s specific needs.

My child tried HBOT and seemed to improve. What does that mean? Individual outcomes can reflect many things: natural development, other therapies running concurrently, or the placebo effect. Without a controlled comparison, it’s not possible to attribute improvement specifically to HBOT. That doesn’t mean the improvement wasn’t real, only that its cause isn’t clear.

What pressure do autism HBOT protocols typically use? Studies like Rossignol (2009) used pressures around 1.3-1.5 ATA. This is lower than medical-grade HBOT used for FDA-approved conditions. For more on pressure differences and what they mean, see what is HBOT.

Where can I find more information about evidence-based autism interventions? The IACC (iacc.hhs.gov) and the Autism Science Foundation are good starting points. Your child’s developmental pediatrician or neurologist can help evaluate treatment options based on your child’s individual profile.

For more on HBOT uses and conditions, visit the conditions hub. For an overview of what HBOT does and how it works, see what is HBOT.

References

Brignell, A. et al. (2019/2020). Cochrane review on hyperbaric oxygen therapy for autism spectrum disorder: current evidence is insufficient to determine whether HBOT is safe and effective. PMID: 32400879. https://pubmed.ncbi.nlm.nih.gov/32400879/

Medical Disclaimer: This page is for informational purposes only. It does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before pursuing any medical treatment.