Hyperbaric oxygen therapy: Evidence-based uses and unproven claims

Hyperbaric oxygen therapy (HBOT) involves breathing pure oxygen while in a special chamber. This therapy is FDA-approved to treat a variety of serious conditions, but claims of HBOT for treating some other conditions are unfounded.

What is hyperbaric oxygen therapy?

The air we breathe is about 21% oxygen. Hyperbaric oxygen therapy involves breathing 100% oxygen as you rest in a large tube called a hyperbaric chamber. Air pressure inside the chamber is increased up to two and a half times normal air pressure.

The extra oxygen and higher air pressure help your lungs to draw in more oxygen, and your body to move more oxygen from your blood to your organs and body tissues. This promotes healing of injuries and treats various conditions such as decompression sickness, carbon monoxide poisoning, and altitude sickness.

The FDA began to regulate hyperbaric oxygen chambers in 1976, and adopted rules for using the devices in 1979.

How does hyperbaric oxygen therapy work?

Hyperbaric oxygen therapy is usually delivered in a one-person hyperbaric chamber. It can also be given in a special room that can accommodate more than one person.

A hyperbaric chamber is a large enclosed tube that contains a bed. You lie comfortably on your back and breathe the pure oxygen that is pumped into the chamber. Many hospitals have hyperbaric chambers.

An average HBOT session lasts 90 minutes to two hours. Some conditions require just one session of hyperbaric oxygen therapy, while others may involve repeated sessions over days or weeks.

You might feel pressure inside your ears while you are in the hyperbaric chamber due to the higher air pressure. Your ears also may pop when you get out of the chamber, similar to going up or down in an airplane.

Conditions that benefit from hyperbaric oxygen therapy

The FDA has approved hyperbaric oxygen therapy to treat a number of conditions, including:

• wounds that are difficult to heal, such as diabetic foot ulcers
• infections and swelling
• severe, large burns
• frostbite
• gas gangrene (a bacterial infection that destroys blood cells and soft tissues)
• air and gas bubbles in blood vessels
• sudden, unexplained hearing loss
• carbon monoxide poisoning
• decompression sickness in divers
• damage from radiation given to treat conditions such as cancer
• severe anemia when blood transfusions cannot be used.

Most insurance plans, including Medicare, will cover some or all of the cost of HBOT in a hyperbaric chamber, as long as it is for an FDA-approved condition.

Conditions without scientific backing for treatment with HBOT

Some treatment centers claim that hyperbaric oxygen therapy can treat a range of other conditions, such as Alzheimer's disease, autism, cancer, and Lyme disease. But the FDA has not cleared or approved the use of HBOT for these conditions.

Risks and side effects of hyperbaric oxygen therapy

Hyperbaric oxygen therapy for FDA-approved conditions is considered safe. Complications of HBOT are uncommon, but they can occur. These include ear and sinus pain, rupture of the eardrum, temporary vision changes, and, rarely, lung collapse. Facilities that provide hyperbaric oxygen therapy are carefully regulated to ensure they are delivering the therapy properly.

High concentrations of oxygen also pose the risk of fire. For this reason, the FDA recommends HBOT treatment only at an accredited facility.