What is hyperbaric oxygen therapy? A plain-English guide
Hyperbaric oxygen therapy, usually shortened to HBOT, means breathing concentrated oxygen while you sit or lie inside a chamber pressurized above normal air pressure. "Hyper" means more and "baric" means pressure, so the name simply describes it: oxygen at higher pressure.
What actually happens
You enter a chamber, the door is sealed, and the pressure is raised slowly over several minutes. Once it reaches the target level, you relax and breathe for the length of the session, usually about an hour. Then the chamber is brought back to normal pressure just as gradually, and you step out.
There are two main types of chamber:
- Monoplace chambers hold one person. Many are clear acrylic tubes you lie down in; others are hard-shell units you sit in.
- Multiplace chambers are room-sized and hold several people at once, usually breathing oxygen through a mask or hood. These are mostly found in hospitals.
Why pressure matters
At normal air pressure, almost all of the oxygen in your blood rides on red blood cells, and only a tiny amount dissolves in the liquid part of the blood (plasma). When you breathe concentrated oxygen under pressure, far more oxygen dissolves directly into the plasma. That extra oxygen can reach tissues that are short on it. We explain the physics in How HBOT works.
Who uses HBOT?
HBOT is used in two quite different settings:
- Hospitals and wound centers use higher-pressure chambers to treat specific medical conditions, such as decompression sickness in divers, carbon monoxide poisoning and certain wounds that won't heal. See The FDA-cleared uses of HBOT.
- Wellness centers offer sessions, often at lower pressures, to people who want to include HBOT in a recovery or wellness routine.
It's important to keep these apart. The strong evidence for HBOT is for a defined list of medical conditions. Claims that it treats or cures other illnesses are not supported, and the FDA has warned consumers about them. Our article HBOT for wellness: separating hype from evidence goes into this.
Is it right for me?
Most healthy adults tolerate HBOT well, but it isn't for everyone. Some lung conditions, recent ear or sinus problems and certain medications mean you should wait or skip it. Every reputable provider will screen you first. Read Who should not do HBOT before your first visit, and check with your doctor if you have any health conditions.