Hyperbaric oxygen therapy (HBOT) involves breathing pure oxygen while in a sealed, pressurized chamber (up to 3 times normal atmospheric pressure). HBOT is used in conventional medicine for very specific reasons - to treat decompression sickness ("the bends," a painful and potentially dangerous condition experienced by divers who surface too quickly), and carbon monoxide poisoning, as well as to speed stroke recovery, and promote healing of complicated wounds, skin infections, and radiation burns.
Tissues in the body require an adequate oxygen supply for normal functioning and even more to survive injury. HBOT increases the amount of oxygen the blood can carry, which raises or temporarily restores normal levels of blood gases and tissue function to promote healing and to fight infection.
Most HBOT chambers accommodate one person, although larger ones can hold more than a dozen people at a time. In a single-person chamber, the patient lies on a table that slides into a clear plastic tube about seven feet long. The chamber is then closed and gradually pressured with oxygen. During the treatment session (from 30 minutes to two hours) you lie still, try to relax and breathe normally. At the end of the treatment, the chamber is gradually depressurized.
Apart from its medically recommended uses, I’ve seen HBOT promoted as a cure for cancer, a treatment for chronic fatigue syndrome, a way to reduce allergy symptoms as well as a beneficial measure for persons with AIDS, arthritis, sports injuries, multiple sclerosis, autism, stroke, cerebral palsy, senility, cirrhosis, Lyme disease, and ulcers. I've seen no persuasive scientific evidence that HBOT can help patients with these conditions. Nor have I seen evidence that lying in an HBOT chamber provides any general or unspecified health benefits.
You should be aware that, although medically useful for diving emergencies and some infections, HBOT is not without risk. It can induce claustrophobia, fatigue and headache. More serious potential problems include short-sightedness (myopia) that can last for months after treatment, sinus damage, middle ear rupture and lung damage. HBOT can worsen symptoms of congestive heart failure and can lead to collapsed lung in patients with some types of lung disease. Too much oxygen can also cause seizures. HBOT is not recommended to address any condition in pregnant women except when there are no other treatment options.
Andrew Weil, M.D.