Efficacy of Hyperbaric Oxygen Therapy for Autism

The use of hyperbaric oxygen therapy for the treatment of autism is relatively recent and so there is not a great deal of scientific evidence specifically related to it, but some positive study results are beginning to come in. At the same time, there are many testimonies from families that have used HBOT as an autism treatment for their autistic children and the results have mostly been encouraging.

To gauge the efficacy of HBOT, the brain can be monitored for its perfusion – the extent to which it is supplied by blood – and its activity. At the same time, we can monitor the behavior, response to stimuli (sensory function) and motor skills of the autistic individual, to determine if hyperbaric oxygen therapy has produced any positive results. In addition, hyperbaric oxygen therapy has been used for many years – and proven effective – in the treatment of cerebral palsy, which involves serious damage to brain cells.

Brain SPECT scans

Monitoring of cerebral blood flow can be done with a Brain SPECT (Single Photo Emission Computed Tomography) scan. SPECT scans before and after mild HBOT sessions have shown dramatic improvements in cerebral blood flow that is sustained over time.

hbot before hyperbaric oxygen therapy hbot after hyperbaric oxygen therapy

The above picture (taken from Rapid Recovery Hyperbarics) show the SPECT scans of a 17-year-old autistic individual before HBOT. The picture below shows his SPECT scan after 50 sessions, done between several times a day and once weekly. The improvement in blood supply continued to be evident one year after HBOT.

The patient also showed improvements in social skills and grades, and a reduction in seizures, after Hyperbaric Oxygen treatments. Three recent small studies conducted independently at three different centres showed significant improvement in behavior ratings scales with mild hyperbaric therapy. Improvements were reported in the areas of:

  • Cognitive ability
  • Socialization
  • Sleep
  • Calmness
  • Decrease in stimming (self-stimulating behavior)
  • Language

These improvements seem to correlate with the improved cerebral blood flow that has already been documented. Larger studies and more ongoing research may be needed before the results can be conclusive, but the initial findings are very promising.

Immunity / Intestinal health

In addition to impacting cerebral blood flow in injured brains, mild hyperbaric oxygen therapy has been shown to positively impact natural killer cell function. Thus, it enhances immune function. HBOT has also been found to reduce inflammatory conditions and has facilitated improvement in gut disease such as Crohn’s Disease and ulcerative colitis. All microorganisms that infect the human body depend on creating or enhancing an oxygen-deprived environment in the body to enhance their survival – this includes viruses, bacteria, yeast, and parasites. These microorganisms are associated with worsening the symptoms of autism.


Studies have also shown HBOT to increase glutathione levels by 15 percent for at least 24 hours after therapy.

Glutathione is vital to the detoxification and excretion of heavy metals such as mercury. Heavy metal poisoning is strongly linked to autism and people with less active glutathione are not able to eliminate heavy metals as quickly and effectively.

These areas are all of interest in the treatment of Autism Spectrum Disorders (ASD) as they are often impaired in children with ASD.

Treatment with mild HBOT

Most patients report improvement during the first 10 to 20 sessions of HBOT. However, it may take 40 to 100 sessions in total to experience the full benefit.

hbot - hyperbaric oxygen chamber 

Hyperbaric oxygen chamber treatments are completely compatible with all other DAN!-based treatments, including chelation. It may even enhance the effectiveness of heavy metal detoxification and other treatments.

An adult is required to accompany all children in the hyperbaric oxygen chamber. The chamber is large enough for an adult to sit up, and long enough to lie down comfortably. One can lie down and take a nap, or sit up and read a book or listen to music – whatever you like. Children and / or adults can use electronic equipment such as a Game Boy, CD player, DVD player, lap-top computer, cell phone, etc. – anything that is battery operated. Children are allowed to drink water, as long as care is taken not to spill. This helps them adjust to the pressure felt in the ears, just as in an aeroplane.

The mild increase in air pressure in the hyperbaric oxygen chamber – a maximum of about 4 psi, (pounds per square inch) or 1.3 ATA, is the equivalent of diving to a depth of about 3 metres of water. The initial ‘dives’ are very closing monitored so that the pressurization and depressurization are prolonged to minimise ear discomfort. For parents who suffer from anxiety in enclosed spaces, it is recommended that a few dives be made initially without the child. Very few people actually suffer from real claustrophobia.

Although there is an attendant during the 50 to 60 minutes of treatment, parents are taught how to safely let themselves out of the chamber from the inside. This level of self-control helps to make people less anxious. For the children, it normally takes three to four sessions before they get used to the pressure. After that, they feel so good that they want to jump in immediately. Fathers and mothers may also wish to take turns to go in, as hyperbaric oxygen therapy helps their alertness as well.


Here is what some families have said about mild HBOT (from the US based Hyperbaric Association):

  • Roman Adams, 6 yrs: Roman’s SLT (speech & language therapist) kept asking us, "What’s different? What new thing are you doing – because he’s definitely changed.
  • Natasha Pruitt: In the last year and 3 months, Natasha has developed a personality and shows interest in things now.
  • Josh Robinson: Josh had just spoken his first real word after just 1 hour in the chamber…now he is verbal with very little delay.
  • Will Robinson: The most significant positive change has been his socialization skills…Will did absolutely fantastic, finally spending the night away from home.
  • Jordan Prickett, 7yr: His teacher at school, who did not know we were doing anything new, told me how pleased she was with his progress in speech!
  • Luke Graves, 4yr: After 68th session: He is initiating conversation by asking questions – this is a giant step!

Ongoing research will help to explain with greater precision how exactly mild HBOT improves the health and well being of our children. The anecdotal reports from parents of significant improvement are being borne out by SPECT scans and behavioral ratings scales. We now have a significant addition to the tool box used in recovering our children.