Hyperbare zuurstoftherapie betekent het inademen van zuurstof in een kamer die op een druk wordt gebracht die ver boven de normale ligt, waardoor het bloed veel meer zuurstof vervoert dan gebruikelijk. Voor een gedefinieerde reeks aandoeningen is het effectieve geneesmiddel. Het is de standaardbehandeling voor decompressieziekte en ernstige koolmonoxidevergiftiging. Het versnelt de genezing van hardnekkige diabetische voetulcera, door bestraling beschadigd weefsel en plotselinge gehoorverlies dat vroeg wordt opgemerkt.
Rondom die kern verkoopt een grote welzijnsmarkt het voor veroudering, de hersenen en herstel. Deze claims berusten op kleine studies, vaak uitgevoerd met zachte kamers met lage druk die minder zuurstof leveren. Onafhankelijk onderzoek heeft nog geen voordeel voor deze welzijnsgebruiken bevestigd.
Findings & Outcomes
What It Is
Inside a sealed hyperbaric chamber the pressure runs to roughly two to three times normal atmospheric pressure. At that pressure far more oxygen than usual reaches tissue that was starved of it. A full course is many sessions, often forty, each about ninety minutes. Two very different uses share the one name. One is a defined set of approved medical conditions treated in hospitals. The other is a much larger wellness market where the evidence is thinner or the equipment weaker.
Anatomy of the Practice
1Under pressure
In the pressurized chamber, high-concentration oxygen reaches tissue that a poor blood supply or low red-cell delivery would otherwise leave starved.
2In starved tissue
The extra oxygen reaches wounds, infected tissue, and radiation-damaged areas that were short of it. Over a course of sessions this is where its healing effects take hold.
3Over a course
A single visit does little; the wound-healing and tissue effects build over a course of weeks. The wellness market applies the same long, repeated dosing to claims the evidence does not yet support.
What It Does
The approved uses rest on controlled trials and long practice:
- In serious carbon monoxide poisoning, a double-blind trial gave three hyperbaric sessions. Lasting thinking problems at six weeks fell from 46% to 25%, and the gap was still present a year later.
- For stubborn diabetic foot ulcers, adding hyperbaric oxygen to standard wound care roughly doubled the share that fully healed within a year, 52% against 29%.
- Recompression with oxygen has long been the standard of care for decompression illness in divers.
- For tissue damaged by earlier radiation treatment, it improves healing and resolution, most clearly in the head, neck, jaw, bladder, and rectum.
- Given early after sudden unexplained hearing loss, it raises the chance of some hearing recovery; started after six months, it does not help.
The wellness claims are weaker. In a controlled trial of 63 healthy older adults, hyperbaric oxygen improved attention and processing speed. The trial was better designed than most wellness studies here. It used an untreated control instead of a sham, and it stands alone. The bigger claims (aging, the brain, long COVID, fibromyalgia, recovery) are weaker still. In autism, where families meet aggressive marketing, the pooled studies are weak and inconsistent. The stronger blinded trials show no clear effect, so the question is unsettled. These wellness lines come largely from one research group, in conditions strongly shaped by expectation. They are preliminary signals. They need independent replication before they can be called established. They are also genuinely interesting: early hints that could become real protocols if independent trials confirm them.
Medical hyperbaric oxygen means 100% oxygen at high pressure in a hospital-grade chamber. Much of what is sold for wellness is a soft chamber, pressurized only slightly above ambient and often filled with ordinary air or a modest oxygen boost. It is a different intervention that delivers far less oxygen.
The Research & Studies
Everything here is based on the research we have collected and checked, sorted into groups and ordered with the strongest evidence first. Click any claim to open the studies behind it.
Cognition
After carbon monoxide poisoning, lasting thinking problems at six weeks fell from 46% to 25%
People treated with three hyperbaric oxygen sessions after carbon monoxide poisoning were about half as likely to have lasting memory and thinking problems at six weeks, 25% against 46%, and the difference held a year later.
In a double-blind randomized trial of adults with acute carbon monoxide poisoning, three hyperbaric oxygen treatments within 24 hours reduced cognitive sequelae at six weeks to 19 of 76 (25.0%) versus 35 of 76 (46.1%) in the sham arm, P=0.007, an adjusted odds ratio of 0.45 (95% CI 0.22 to 0.92). The benefit persisted at 12 months (P=0.04). This is the trial that anchors CO poisoning as an approved indication, though other trials have been less clear-cut and the ideal number and timing of sessions is still argued.
This is an emergency treatment given in hospital soon after a serious exposure, not something a person arranges for themselves. The practical point for a reader is that a suspected significant CO exposure is a reason to get to emergency care quickly, where hyperbaric oxygen is one of the tools available.
The study · 1
Weaver et al., hyperbaric oxygen for acute carbon monoxide poisoning · N Engl J Med 2002;347(14):1057-67
In one trial of 63 healthy older adults, attention and processing speed improved
In healthy older adults, a long course of hyperbaric oxygen improved attention and mental processing speed compared with an untreated group, and brain blood flow rose.
In a randomized controlled trial, 63 healthy adults over 64 (33 treated, 30 controls) received 60 sessions over 90 days. The treated group showed a significant group-by-time improvement in global cognitive function, with net effect sizes of 0.745 for attention and 0.788 for information processing speed, and increased cerebral blood flow in frontal and parietal regions. It is a controlled trial, which lifts this above the uncontrolled aging work, but it is one study in a specific population, its control group was untreated instead of sham, and durability and everyday meaning are not yet established.
Read this as an early controlled signal in healthy aging, not a settled reason to undertake a costly 60-session course. A single trial with an untreated, not sham control needs replication before it guides a decision.
The study · 1
Hadanny et al., cognitive enhancement of healthy older adults using hyperbaric oxygen · Aging (Albany NY) 2020;12(13):13740-13761
Skin And Hair
Hyperbaric oxygen healed 52% of stubborn diabetic foot ulcers within a year, against 29% on standard care
Adding hyperbaric oxygen to standard wound care roughly doubled the share of stubborn diabetic foot ulcers that fully healed within a year, 52% against 29%.
In a randomized, double-blinded, placebo-controlled trial of 94 patients with diabetes and chronic foot ulcers, 40 sessions over eight weeks produced complete healing at one year in 25 of 48 (52%) with hyperbaric oxygen versus 12 of 42 (29%) with sham air (P=0.03). Among patients completing more than 35 sessions the difference widened to 23 of 38 (61%) versus 10 of 37 (27%), P=0.009. The effect depends on finishing a demanding course of treatment, and it applies to selected patients with wounds that have resisted standard care, not to diabetic ulcers in general.
This is an adjunct to good wound care, blood-sugar control, and vascular assessment, and it works alongside them. Raise it with a wound-care team for an ulcer that is not healing despite proper standard treatment, and keep in mind that the benefit came from completing the full course.
The study · 1
Löndahl et al., hyperbaric oxygen therapy facilitates healing of chronic foot ulcers in patients with diabetes · Diabetes Care 2010;33(5):998-1003
Faster short-term ulcer healing, but no reduction in major amputations
Across the randomized trials, hyperbaric oxygen helped diabetic foot ulcers heal faster in the short term, but did not clearly lower the chance of losing a limb.
A Cochrane review included 12 randomized trials (577 participants). A pooled analysis of 5 trials (205 participants) found hyperbaric oxygen improved healing of diabetic foot ulcers at six weeks (RR 2.35, 95% CI 1.19 to 4.62) but not at one year, and a pooling of 5 trials (312 participants) found no statistically significant reduction in major amputation (RR 0.36, 95% CI 0.11 to 1.18). The reviewers rated the trials as often small and at risk of bias and called for higher-quality studies. So the short-term healing signal holds while the limb-salvage claim, which is what patients care about most, is not established.
The realistic expectation to set is faster healing of a selected ulcer, not a demonstrated reduction in amputations. That distinction matters when weighing a demanding course of treatment.
The study · 1
Kranke et al., hyperbaric oxygen therapy for chronic wounds · Cochrane Database Syst Rev 2015
Hyperbaric oxygen improved healing of radiation-damaged tissue (risk ratio 1.39)
For tissue damaged by earlier radiation treatment, hyperbaric oxygen made healing and resolution more likely, especially for the head and neck, jaw, bladder and rectum.
A Cochrane review of 18 randomized trials (1,071 participants) found hyperbaric oxygen improved complete resolution or significant improvement of late radiation tissue injury (RR 1.39, 95% CI 1.02 to 1.89) and reduced wound dehiscence after operations in irradiated tissue (RR 0.24, 95% CI 0.06 to 0.94), with moderate-certainty evidence for pain improvement in mandibular osteoradionecrosis at 12 months. Benefits were seen for head, neck, bladder and rectal tissue. The same review recorded harms: a higher risk of reduced visual acuity (RR 4.03) and of ear barotrauma, and it called for more rigorous trials.
This is one of the better-supported approved uses, delivered through a hospital hyperbaric unit for radiation damage that is not settling on its own. The benefit is weighed against a real course cost and the ocular and ear risks the same evidence documents.
The study · 1
Lin et al., hyperbaric oxygen therapy for late radiation tissue injury · Cochrane Database Syst Rev 2023
How it works
Recompression with oxygen is the established treatment for decompression illness in divers
Putting a diver with the bends back under pressure with oxygen is the established treatment. The randomized trials that exist tested add-ons to that treatment, not the treatment itself.
Recompression in a hyperbaric chamber breathing oxygen is the accepted standard of care for decompression illness and arterial gas embolism, resting on physiology and long clinical experience, not placebo-controlled trials, since withholding recompression to form a control group would be unethical. A Cochrane review found only 2 randomized trials (268 patients), both of adjuncts: adding a non-steroidal anti-inflammatory did not improve the odds of recovery (RR 1.04, 95% CI 0.90 to 1.20), while a heliox table reduced the odds of needing multiple recompressions. So the core treatment is well established while the formal randomized base is thin and concerns refinements.
For anyone who dives, the practical point is that decompression illness is a medical emergency treated by recompression, and that the surface first aid is high-flow oxygen while arranging transfer to a chamber.
The study · 1
Bennett et al., recompression and adjunctive therapy for decompression illness · Cochrane Database Syst Rev 2012
Vision
Vision drifts about 0.58 to 0.61 diopters more short-sighted over a course, usually reversing afterward
A course of hyperbaric oxygen commonly makes vision slightly more short-sighted, by a small amount that grows over the sessions and generally reverses after treatment ends.
In a series of 44 eyes of diabetic patients followed across 30 treatments, hyperbaric oxygen produced a small myopic shift, statistically significant at about 0.58 to 0.61 diopters, that appeared from the first treatment and tracked the number of sessions. Oxygen-induced changes in the lens are a recognized effect of repeated hyperbaric treatment and usually reverse over weeks after a course ends, though longer intensive courses have also been linked to cataract progression. It is a nuisance side effect, not a dangerous one, but it explains why vision can blur during a course.
The practical note is to expect some temporary blurring during a long course and to hold off on updating a glasses prescription until vision settles for several weeks after treatment finishes.
The study · 1
Andrawus-Haddad et al., the rate of development of myopia during hyperbaric oxygen therapy · Harefuah 2010
Hearing And Tinnitus
Started early, hyperbaric oxygen raised the chance of hearing recovery about 22%; after six months it did not help
Given soon after sudden unexplained hearing loss, hyperbaric oxygen raised the chance of some hearing recovery, with a threshold gain around 15 decibels. Starting late, after months, did not help.
A Cochrane review of 7 randomized trials (392 participants) found that for acute idiopathic sudden sensorineural hearing loss, hyperbaric oxygen produced a 22% greater chance of improvement (NNT 5) and a mean 15.6 dB greater improvement in hearing threshold. There was no significant benefit for chronic presentations treated after six months. The reviewers judged the clinical significance uncertain and the trials small, so this sits as an emerging use, not a settled one, and timing appears to matter.
Because the signal is tied to early treatment, speed matters: sudden unexplained hearing loss is a same-week medical matter, and hyperbaric oxygen is one option a specialist may add early, not months later.
The study · 1
Bennett et al., hyperbaric oxygen for idiopathic sudden sensorineural hearing loss and tinnitus · Cochrane Database Syst Rev 2012
Pain
In an open-label trial of 60 women, hyperbaric oxygen eased fibromyalgia pain
In a crossover trial of women with fibromyalgia, a course of hyperbaric oxygen eased pain and improved quality of life, alongside shifts in brain-imaging patterns.
In a prospective crossover trial, 60 women with fibromyalgia (ages 21 to 67) received 40 sessions at 100% oxygen. Both the immediately treated group and the crossover group showed significant improvement across fibromyalgia symptoms and quality of life, with corresponding changes in brain activity on SPECT imaging. The crossover design strengthens it, but the trial was unblinded, studied only women, and a condition that responds strongly to expectation makes an open-label result hard to separate from placebo. It marks fibromyalgia as an emerging use worth watching, not an established treatment.
Who this may not transfer to:Measured only in women. Fibromyalgia is far more often diagnosed in women, and this trial enrolled none, so the size of any effect in men is unknown, not assumed to be similar.
The reasonable stance is interest tempered by the design: an open-label result in a highly expectation-sensitive condition is not yet a basis for committing to an expensive course. It is a candidate for a properly blinded trial.
The study · 1
Efrati et al., hyperbaric oxygen therapy can diminish fibromyalgia syndrome, prospective clinical trial · PLoS One 2015;10(5):e0127012
Energy And Fatigue
In long COVID, sleep and pain gains from a sham-controlled trial persisted past a year in an uncontrolled follow-up of 31 patients
In a randomized trial in long COVID, a course of hyperbaric oxygen improved quality of life, sleep and pain, and a follow-up found the gains were still present more than a year later.
A sham-controlled randomized trial gave 40 sessions to long COVID patients and found short-term benefit; this longitudinal follow-up then re-evaluated 31 of the treated patients about 486 days after the last session. Measured against baseline, improvements in quality of life, sleep (effect sizes 0.47 to 0.79), pain severity (0.69) and interference (0.83), and neuropsychiatric symptoms persisted at more than a year. The sham arm had crossed over to hyperbaric oxygen and was not followed long-term, so the persistence rests on an uncontrolled within-group comparison, not a controlled one. The samples are small, the work comes largely from one group, and long COVID improves over time on its own, so this is an emerging use that needs replication by independent teams.
For long COVID the grounded reading is cautious optimism: a small sham-controlled trial with lasting gains is more than most proposed treatments have, and it is still one line of evidence from one group, not yet a reason to expect the same for everyone.
The study · 1
Hadanny et al., long term outcomes of hyperbaric oxygen therapy in post covid condition · Sci Rep 2024
Longevity And Mortality
In 35 older adults with no control group, immune-cell telomeres lengthened over 20%
In a small study of older adults with no comparison group, a long course of hyperbaric oxygen was followed by longer telomeres in immune cells and fewer worn-out cells, which is the finding behind the reverse-aging headlines.
In a prospective trial, 35 healthy adults aged 64 and over completed 60 hyperbaric sessions over 90 days. Telomeres of T-helper, T-cytotoxic, natural killer and B cells lengthened by more than 20% (B-cell telomeres by 37.63% after treatment), and senescent T-helper cells fell by 37.30%. The result is striking and it is the origin of the anti-aging claims, but the design allows only a limited conclusion: 35 people, no control group, blood-cell markers, not health outcomes, and a research team with a commercial interest in the therapy. Whether longer telomeres in circulating immune cells translate into living longer or better is a further question this study does not answer.
The useful reading is to treat this as an early mechanistic signal worth watching, not a reason to buy a course of treatment. Marker changes in blood cells are a long way from a demonstrated effect on how long or how well a person lives.
The study · 1
Hachmo et al., hyperbaric oxygen therapy increases telomere length and decreases immunosenescence in isolated blood cells · Aging (Albany NY) 2020;12(22):22445-22456
Neurodevelopmental
Pooled weak studies suggested benefit for autism, but rigorous blinded trials show no clear effect
A pooled analysis of small studies reported improvements in autism symptoms with hyperbaric oxygen, but the studies were weak and inconsistent, and the most rigorous sham-controlled trials have not found a clear effect.
A 2025 systematic review and meta-analysis pooled 17 studies (890 children and adolescents) and reported moderate-to-large improvements in core autism symptoms (SMD -0.66), communication (-0.88), cognitive awareness (-0.93) and behavior (-0.80). The reviewers themselves flagged low study quality, heterogeneity, and the need for high-quality trials before efficacy can be confirmed. Pooling weak and mixed studies can generate a positive number that stronger, blinded designs do not reproduce, which is why the direction here is left open, not called a benefit. Families face aggressive marketing of this use, so the gap between the marketing and the evidence matters.
The practical takeaway for a family is restraint: the marketing runs well ahead of the evidence, the well-controlled trials have not shown a clear effect, and the cost and time are substantial, so this is not a use to pursue on the strength of the claims made for it.
The study · 1
Tu et al., the effectiveness of hyperbaric oxygen therapy in children and adolescents with autism spectrum disorders, systematic review and meta-analysis · Prog Neuropsychopharmacol Biol Psychiatry 2025
How It Works
Oxygen normally travels bound to hemoglobin in the red cells, which sit nearly full at sea level, so breathing extra oxygen at normal pressure adds little. Raise the pressure and a large quantity dissolves directly into the plasma, several times the usual amount. That plasma-borne oxygen diffuses into tissue the red cells reach poorly.
The strongest uses are all cases of oxygen starvation: a wound that will not heal, radiation-scarred tissue, an infection in poorly perfused tissue, or blood loaded with carbon monoxide.
Repeated sessions do four things:
- promote new blood-vessel growth into damaged areas
- help certain white cells make the reactive molecules they use to kill bacteria
- reduce tissue swelling by constricting overdilated vessels
- in carbon monoxide poisoning, speed the gas out of the blood and limit the inflammatory injury that follows
Like heat and cold exposure, this is a controlled, repeated stress, the idea behind hormesis. Much of its action turns on the mitochondria and the vessel wall. For the approved uses the mechanism is well understood.
Getting It Right
Delivered under medical supervision, hyperbaric oxygen is prescribed, not self-administered. The decision that matters is whether a given use is on the approved list or one of the wellness claims.
Ways to Do It
The moves below sort where a given claim sits in the evidence.
The approved list is specific: decompression illness, carbon monoxide poisoning, gas embolism, non-healing diabetic foot ulcers, radiation tissue injury, sudden hearing loss caught early, and certain severe infections. Anti-aging, general brain-boosting, and sports recovery are not on it. A claim on the approved list carries the weight of controlled trials and long practice; a claim off it does not.
For a condition on the approved list, hyperbaric oxygen is delivered through a hyperbaric unit on referral from a clinician, as a course of many sessions. It is an adjunct to good standard care and works alongside it. It is generally most useful when standard treatment alone has not resolved the problem.
For a serious problem, hyperbaric oxygen belongs alongside standard treatment, with a clinician overseeing the case. It is an addition to proven care, not a replacement for it.
Go Deeper
- Hormesis: how a controlled, repeated stress leaves tissue sturdier.
- Heat exposure: the sauna evidence for blood vessels and blood pressure.
- Cold exposure: what cold does, and how it is often paired with heat.
The Chinese Medicine View
Hyperbaric oxygen is a modern hospital technology, so no classical Chinese medicine teaching addresses it.
The tradition does hold a related idea. The Lung draws in Da Qi, the clear Qi of air. That clear Qi combines with the essence the Spleen extracts to form the body Qi, the vitality that moves and defends the body.
High-pressure oxygen can be mapped onto that idea, and some wellness marketing frames the chamber as filling the body with clear Qi. But Qi is a functional idea: transformation, movement, and defense across the whole body. The two accounts share only a loose idea: that breath brings in something the body needs. The mapping is an interpretation only.
Cautions For This Practice
Everything to be aware of is here, in one place. This practice suits most healthy people; a few situations call for real care.
Ear barotrauma, the commonest side effect, affects about 15% of patients
A 2025 systematic review of otologic adverse events found that about 15% of 18,284 patients treated with hyperbaric oxygen experienced an ear-related adverse event, predominantly middle ear barotrauma; of those, 42.8% were mild and 6.4% severe. Risk was higher with advancing age, female sex, head and neck pathology, sensory neuropathy and pre-existing difficulty equalizing ear pressure. Effective equalization technique was the main protective factor. Most cases are minor and manageable, and the pattern points to who needs extra care and teaching before treatment.Voigt et al., systematic review of otologic adverse events in hyperbaric oxygen therapy
Oxygen-toxicity seizures are rare, about 1 in 2,000 sessions, and leave no lasting harm
In a retrospective single-center series of 10,425 treatment sessions across 1,308 patients, five central nervous system oxygen toxicity seizures occurred, an overall rate of 0.048% of sessions. The rate was higher in carbon monoxide poisoning (0.148%) and markedly higher in arterial gas embolism (3.448%). No seizure caused lasting effects. These events are rare and self-limiting once oxygen is removed, and units manage the risk with air breaks and pressure limits. The higher rate in specific emergency indications reflects both the patients and the more aggressive protocols used for them.Lee et al., seizure during hyperbaric oxygen therapy, experience at a single academic hospital in Korea
Ear And Sinus Barotrauma Is The Common Side Effect
The pressure change can injure the middle ear, the most frequent complication, affecting about one in seven patients, and usually mild. Older age, prior ear trouble, and difficulty equalizing raise the risk. Learning ear-clearing techniques, slower compression, and treating congestion beforehand reduce it. Sinus and, rarely, lung barotrauma can also occur.
Oxygen Toxicity Can Rarely Trigger A Seizure
Breathing oxygen at high pressure can rarely cause a central nervous system oxygen toxicity seizure. It is uncommon, on the order of one in a couple of thousand sessions in general use, and higher in carbon monoxide and gas embolism cases. It resolves once oxygen is removed, with no lasting harm. Units manage it with scheduled air breaks and pressure limits.
Contraindications And Who Needs Extra Care
An untreated pneumothorax, a collapsed lung, is the clearest reason to avoid a chamber, because trapped air expands as pressure changes. Certain lung diseases, some chemotherapy drugs, recent ear or chest surgery, uncontrolled high fever, and claustrophobia all call for medical assessment first. Vision can shift slightly toward short-sightedness during a long course and usually settles within weeks after it ends, so hold off on updating a glasses prescription until then.
A Full Course Takes Weeks, And Fire Is A Managed Hazard
The course runs to many sessions over weeks, a large commitment of time. Because the chamber is oxygen-rich, fire is a serious hazard, so units forbid certain materials and devices inside.
The Wellness Claims Are Not A Reason To Delay Proven Care
The anti-aging, cognitive, long COVID, fibromyalgia, and autism uses rest on small or uncontrolled studies, and often on soft chambers that differ from the medical version. The real risk is choosing an unconfirmed course instead of care proven for the same problem. Treat these as areas still being tested, and keep any serious condition under a doctor's care.
Start slow, be smart, read the research, and consult a professional if you have any concerns. This is here to inform your choice, not make it for you.
Common Questions
Does Hyperbaric Oxygen Reverse Aging?
The widely shared study lengthened telomeres by more than 20% and cut the load of worn-out cells in the blood of 35 healthy older adults. It had no comparison group. It measured cell markers in the blood, and nothing a person would actually feel, such as living longer or better. So it is a suggestive laboratory result, far from evidence that the therapy slows aging.
Does It Help Long COVID Or Fibromyalgia?
In long COVID, a small sham-controlled trial found short-term gains in quality of life, sleep, and pain. A later follow-up re-examined only the treated patients, without a control group, and reported their gains still present more than a year on. In fibromyalgia, an open-label crossover trial in women eased pain and improved quality of life. Both come from small samples, so read them as early and unconfirmed.
Does It Prevent Amputations In Diabetic Foot Disease?
It speeds the short-term healing of selected diabetic foot ulcers. Pooled across the randomized trials, though, it did not significantly lower the rate of major amputation, the outcome patients care about most.
So it can help a wound close faster without changing whether a limb is ultimately lost.
Explore Related
Other pages this one connects to, by the evidence they share, the outcomes they touch, and the ground they cover.
All 14 sources on this page independently checked and cross-referenced.
Thomas Dehli, Founder & Editor, Sacred Lotus
Sacred Lotus has published Chinese medicine reference material since 2001. Integrative pages are held to the same standard as the herb and formula library: cite the source, grade the claim at its real strength, and say where the research has not looked. This page is educational and it is not medical advice. Last reviewed and updated August 9, 2026.
Evidence strength
How confidently the research supports a claim. Strength describes the evidence, not our endorsement.