If a wound isn’t healing the way it should, if you’re recovering from radiation treatment, or if you’ve simply heard that “oxygen therapy” is being used for everything from athletic recovery to anti-aging, you’ve probably come across the term hyperbaric oxygen therapy (HBOT). It’s one of the older and better-studied treatments in modern medicine — first used for decompression sickness in divers decades ago — but it’s also one of the most misunderstood, partly because it’s now marketed for far more than its proven, FDA-recognized uses.

This guide separates the two clearly: what hyperbaric oxygen therapy is actually approved and well-evidenced for, and what remains investigational or wellness-oriented. Along the way, we’ll explain the physiology behind why breathing pressurized oxygen can support healing, walk through what a session looks like, cover safety considerations, and answer the questions patients ask most often before starting treatment.

Medical disclaimer: This article is for educational purposes only and is not a substitute for professional medical advice. Hyperbaric oxygen therapy should only be administered under the supervision of a qualified physician at an accredited facility. Always consult your healthcare provider to determine whether HBOT is appropriate for your specific condition.

• HBOT involves breathing near 100% oxygen inside a pressurized chamber, which allows significantly more oxygen to dissolve into blood plasma and reach tissues than breathing normal air.
• The FDA and the Undersea and Hyperbaric Medical Society (UHMS) formally recognize a defined list of medical indications for HBOT — currently around 14 conditions — that are backed by clinical evidence and are typically covered by insurance when medically necessary.
• HBOT is also used off-label for conditions such as traumatic brain injury, post-COVID recovery, sports recovery, and general wellness, where evidence is more limited and coverage is usually not available.
• The FDA has specifically warned patients about clinics marketing HBOT for unapproved uses such as cancer, autism, or Alzheimer’s disease, where evidence does not currently support those claims.
• HBOT is generally well-tolerated, but it carries specific risks — including ear barotrauma, oxygen toxicity, and fire hazard — that make treatment at an accredited, physician-supervised facility important.

Definition: Hyperbaric oxygen therapy is a medical treatment in which a patient breathes near 100% oxygen while inside a chamber pressurized above normal atmospheric pressure — typically between 1.5 and 3.0 atmospheres absolute (ATA). The elevated pressure allows oxygen to dissolve directly into blood plasma, cerebrospinal fluid, and other body fluids, not just red blood cells, dramatically increasing the amount of oxygen delivered to tissues.

Under normal atmospheric conditions, oxygen travels through the bloodstream almost entirely bound to hemoglobin in red blood cells. Under hyperbaric conditions, the increased pressure forces additional oxygen to dissolve directly into the plasma itself. This matters clinically because dissolved plasma oxygen can reach tissue that has poor blood supply — such as a chronic wound, a radiation-damaged area, or tissue affected by a compromised skin graft — even when hemoglobin-bound oxygen delivery is limited.

A typical session takes place in one of two chamber types:

• Monoplace chambers, which hold a single patient who breathes pressurized oxygen directly, with the entire chamber filled with oxygen.
• Multiplace chambers, which can accommodate several patients at once, pressurized with air, with oxygen delivered individually through a mask or hood.

Several mechanisms are thought to underlie HBOT’s clinical effects, and they’re relevant to understanding both why it works for its approved indications and why researchers are exploring its use elsewhere:

• Increased tissue oxygenation: More dissolved oxygen reaches tissue that has reduced blood flow, supporting cellular metabolism in areas that would otherwise be oxygen-starved.
• Angiogenesis (new blood vessel growth): Repeated hyperbaric exposure has been shown to stimulate the formation of new capillaries in previously poorly-vascularized tissue, which is central to its use in chronic wound healing.
• Reduced inflammation and edema: Elevated pressure causes vasoconstriction that can reduce swelling, while still improving net oxygen delivery — a combination useful in crush injuries and compartment syndrome.
• Enhanced white blood cell function: Higher tissue oxygen levels support the oxygen-dependent killing mechanisms neutrophils use against certain bacteria, which is part of why HBOT is used as an adjunct for serious infections like gas gangrene.
• Fibroblast activity and collagen synthesis: Adequate oxygen is required for fibroblasts to produce collagen, a key step in wound healing and tissue repair.
• Reduction of gas bubble size: In decompression sickness and air/gas embolism, increased pressure directly reduces the size of gas bubbles in the bloodstream while accelerating their reabsorption.

Key takeaway: HBOT’s core mechanism — driving more dissolved oxygen into blood plasma and tissue — explains both its strongest, most established uses (wound healing, gas-related emergencies, radiation injury) and the biological rationale researchers are testing in newer, less-established applications.

The FDA and the UHMS jointly recognize a defined list of medical conditions for which HBOT has demonstrated sufficient evidence of safety and effectiveness. As of the current UHMS indications guidance, there are approximately 14 recognized indications, including:

• Carbon monoxide poisoning
• Decompression sickness (diving-related)
• Arterial gas embolism
• Chronic diabetic foot ulcers and other non-healing wounds unresponsive to standard care
• Compromised skin grafts and flaps
• Radiation tissue injury (such as osteoradionecrosis or radiation proctitis following cancer treatment)
• Severe thermal burns (as an adjunct to standard burn care)
• Crush injuries and acute traumatic ischemias
• Gas gangrene (clostridial myonecrosis)
• Necrotizing soft tissue infections
• Refractory osteomyelitis (chronic bone infection)
• Sudden sensorineural hearing loss
• Central retinal artery occlusion
• Severe anemia when blood transfusion is not possible

Key takeaway: These are the indications for which HBOT is generally considered medically necessary, is delivered according to standardized treatment protocols, and is typically covered by Medicare and most private insurers when properly documented.

Myth: Hyperbaric oxygen therapy is approved to treat cancer, autism, or Alzheimer’s disease. Fact: The FDA has specifically warned that these uses are not approved or supported by current evidence, and it has cautioned patients about clinics that market HBOT for such conditions.

Myth: More pressure or longer sessions always produce better results. Fact: HBOT protocols use specific, condition-dependent pressure and duration settings; excessive pressure or session length increases the risk of oxygen toxicity without added benefit.

Myth: HBOT is only for divers with decompression sickness. Fact: While decompression sickness was one of HBOT’s earliest uses, it’s now a recognized treatment across wound care, radiation injury, certain infections, and several other medical specialties.

Myth: All hyperbaric chambers offer the same treatment. Fact: Medical-grade chambers used for FDA-recognized indications operate at higher pressures under physician supervision, while some “mild hyperbaric” or wellness chambers operate at lower pressures with a different — and much more limited — evidence base.

Beyond its FDA-recognized indications, HBOT is used in some clinical and wellness settings for conditions where research is ongoing but not yet conclusive. It’s important to understand that off-label does not necessarily mean ineffective — but it does mean the evidence base is thinner, protocols are less standardized, and insurance coverage is typically unavailable. Current areas of interest include:

• Traumatic brain injury and concussion: Investigational, with some studies suggesting potential benefit for post-concussive symptoms, though it is not FDA-approved for this use.
• Post-COVID recovery and long COVID: Early clinical trials have explored HBOT for patients with persistent hypoxemia or long-COVID symptoms, with encouraging but not yet definitive results.
• Chronic fatigue and general recovery: Used in some wellness and sports-medicine settings, though rigorous clinical evidence remains limited.
• Athletic recovery and performance: Popular among some athletes for post-exertion recovery, based on plausible mechanisms (reduced inflammation, improved tissue oxygenation) rather than large-scale trial data.
• Aging and longevity applications: Preliminary research has examined whether intermittent hyperbaric exposure affects cellular aging markers, an area of active but early-stage investigation.

Because marketing claims in this space can outpace the underlying science, it’s worth asking any HBOT provider directly what evidence supports their specific recommended use, and whether that use is FDA-recognized or considered investigational.

Key takeaway: Off-label HBOT is not inherently unsafe, but patients should distinguish between well-established, insurance-covered indications and emerging uses where evidence, dosing standards, and expected outcomes are still being defined.

Patients often ask how HBOT compares to other regenerative or recovery-focused treatments, particularly for uses like wound healing, tissue repair, and general recovery support.

Some regenerative medicine practices combine approaches — for example, using HBOT to support tissue oxygenation while complementary regenerative treatments target localized cellular signaling. If you’re exploring options across these categories, our overview of exosome therapy explains how cell-free regenerative treatments work and where they may complement therapies like HBOT.

• Medical evaluation: A physician reviews your medical history, current condition, and any contraindications (such as untreated pneumothorax or certain lung conditions) before recommending HBOT.
• Pre-treatment preparation: Patients typically remove jewelry, certain fabrics, and flammable materials, since pure oxygen environments carry fire risk.
• Entering the chamber: You lie or sit comfortably as the chamber is gradually pressurized, similar to the pressure change felt during airplane descent.
• Oxygen delivery: In a monoplace chamber, you breathe the pressurized oxygen directly; in a multiplace chamber, oxygen is delivered through a mask or hood while the chamber itself is pressurized with air.
• Session duration: A typical session lasts 60–120 minutes, depending on the condition being treated.
• Decompression: Pressure is gradually reduced at the end of the session to avoid barotrauma.
• Course of treatment: Chronic conditions like diabetic wounds or osteoradionecrosis often require a series of sessions — sometimes 20 to 40 — administered daily or several times per week, while acute emergencies like carbon monoxide poisoning may require only one to three sessions.

HBOT is generally considered safe when administered by trained providers at an accredited facility, but it is not risk-free. Reported risks include:

• Ear and sinus barotrauma: The most common side effect, caused by pressure changes affecting the middle ear; usually mild and preventable with proper equalization technique.
• Temporary vision changes: Some patients experience myopic shifts after multiple sessions, which typically resolve after treatment ends.
• Oxygen toxicity: Rare but possible with excessive pressure or session duration, potentially affecting the lungs or central nervous system.
• Claustrophobia or anxiety: Some patients find enclosed chamber environments uncomfortable, particularly in monoplace units.
• Fire risk: Pure oxygen environments require strict safety protocols, since oxygen supports combustion; accredited facilities follow rigorous safety standards to minimize this risk.
• Not appropriate for everyone: Certain conditions, including untreated pneumothorax and some chemotherapy regimens, may be contraindications, underscoring the importance of a thorough medical evaluation beforehand.

Key takeaway: The FDA has specifically recommended seeking HBOT at UHMS-accredited facilities, both to ensure appropriate safety protocols and to avoid providers offering the therapy for unapproved, unsupported uses.

Likely appropriate candidates include:

• Patients with a diagnosed, FDA-recognized indication such as a non-healing diabetic wound, radiation injury, or compromised skin graft
• Patients recovering from acute carbon monoxide poisoning or decompression sickness
• Individuals with specific infections where HBOT is used as an evidence-based adjunct to surgery and antibiotics

Who should proceed cautiously or seek further evaluation:

• Patients considering HBOT for off-label or wellness purposes, who should have a clear discussion with their physician about the current evidence and realistic expectations
• Individuals with certain lung conditions, uncontrolled seizure disorders, or specific implanted devices, who require careful pre-treatment screening
• Patients being offered HBOT for conditions the FDA has specifically flagged as unsupported, such as cancer or Alzheimer’s disease, who should seek a second medical opinion

Hyperbaric oxygen therapy is often discussed alongside other regenerative and recovery-focused treatments. You may also find these related resources helpful:

• Learn more about exosome therapy as a complementary regenerative medicine approach
• Explore aging and longevity treatments using regenerative medicine
• Read about exosome therapy for hair loss and how it compares to other regenerative options
• Discover skin rejuvenation treatments that support tissue repair
• Learn about anti-aging regenerative therapies
• Explore facial aesthetics treatments using regenerative medicine

If you’re evaluating whether HBOT or a regenerative therapy is the right fit for your recovery or wellness goals, our team can help you understand how these approaches compare for your specific condition through a personal consultation.

Hyperbaric oxygen therapy is a well-established, physiologically well-understood treatment for a defined set of medical conditions — from chronic non-healing wounds to radiation injury to carbon monoxide poisoning — where the evidence supporting its use is strong and outcomes are well-documented. Outside of these FDA-recognized indications, HBOT is an active area of research for conditions like traumatic brain injury, post-COVID recovery, and general wellness, but patients should approach these uses with realistic expectations and a clear understanding of the current evidence.

Because HBOT carries real, if generally manageable, risks and because marketing claims in this space can outpace the science, treatment should always be pursued through a qualified physician at an accredited facility — not based on generalized wellness claims. A personal medical evaluation is the most reliable way to determine whether HBOT, a regenerative therapy, or a combination approach best fits your specific health needs.