Canada HyperbaricsPatient Guide

Patient Guide: Talking to Your Doctor About HBOT

Plain-language guideReviewed every quarterFor patients and families

A plain-language guide for patients and families in Canada. Hyperbaric oxygen therapy, often shortened to HBOT, is a real medical treatment with a defined and limited set of uses. If you have read about it online, you may have seen everything from sober hospital descriptions to bold claims that it fixes almost anything. The truth sits in a clearer, narrower place. This guide explains what HBOT actually is, the specific conditions it is recognised for in Canada, how to bring it up with your own doctor, what questions to ask, how to read the evidence without being misled, and how to recognise a clinic that is overselling. The goal is to help you have a calm, well-informed conversation, not to talk you into or out of anything.

What HBOT is and is not

HBOT means breathing close to 100 per cent oxygen inside a sealed chamber where the air pressure is raised above the normal pressure at sea level. The higher pressure lets your blood and tissues carry more dissolved oxygen than usual. For certain conditions, that extra oxygen can help the body fight infection, clear harmful gases, and support the healing of tissue that is starved of blood supply. Sessions usually last around an hour to two hours, and depending on the condition you may need a single emergency treatment or a planned course over several weeks.

It is worth being clear about what HBOT is not. It is not a general wellness or anti-ageing treatment. It is not a proven therapy for most chronic illnesses, and breathing extra oxygen is not automatically good for every problem. In Canada, hospital-based hyperbaric programmes use medical-grade chambers run at clinical pressures and treat a defined list of conditions. They do not offer it as a tune-up or a cure-all. When a treatment is genuinely supported by evidence, it is offered for specific reasons; when it is offered for almost everything, that is usually a sign to slow down and ask questions.

HBOT also carries real, if generally manageable, considerations. Because of the pressure changes, people with certain lung or ear conditions may not be suitable candidates, and the treatment is delivered under medical supervision for that reason. This is a medical therapy, not a spa service, and it deserves the same careful conversation you would have about any other treatment.

Diagram of a hyperbaric chamber showing the mechanism of breathing close to 100 per cent oxygen at raised pressure, the increased dissolved oxygen carried to the tissues, and a typical session of one to two hours under medical supervision. — Figure Hyperbaric oxygen therapy means breathing close to 100 per cent oxygen inside a sealed chamber pressurised above normal sea-level pressure, which lets the blood and tissues carry more dissolved oxygen. For certain conditions that extra oxygen can help the body fight infection, clear harmful gases, and support tissue that is starved of blood supply. Sessions typically run about one to two hours under medical supervision. It is a targeted medical treatment, not a general wellness or anti-ageing service, and it is not a proven therapy for most chronic illnesses.

The conditions it is recognised for in Canada

Health Canada recognises hyperbaric oxygen therapy for fourteen specific conditions. These are the uses backed by enough evidence and clinical consensus to be considered established care, and they are the ones publicly covered when delivered through hospital programmes. For a few of them, such as the first three below, HBOT is a primary treatment. For most of the others, it is used alongside standard care such as surgery, antibiotics, or wound care rather than on its own. In plain terms, the fourteen are:

1. Decompression sickness ("the bends"), the diving injury caused by gas bubbles forming in the body after surfacing too quickly. 2. Carbon monoxide poisoning, where a colourless, odourless gas reduces the blood's ability to carry oxygen. This is treated as an emergency. 3. Arterial gas embolism, a dangerous gas bubble in the bloodstream, often related to diving or certain medical procedures. 4. Selected problem wounds that will not heal, such as some diabetic foot wounds, where extra oxygen may support healing alongside standard wound care. 5. Soft tissue radiation injury, damage to soft tissues that can appear months or years after radiation treatment for cancer. 6. Radiation damage affecting bone, a related late effect of radiation, sometimes in the jaw. 7. Gas gangrene, a fast-moving, life-threatening infection that produces gas in the tissues, treated alongside surgery and antibiotics. 8. Crush injuries and sudden loss of blood supply to a limb, used alongside surgery in serious cases. 9. Necrotising soft tissue infections, severe rapidly spreading infections sometimes called "flesh-eating" infections, treated alongside surgery and antibiotics. 10. Compromised skin grafts and flaps, where transplanted or reconstructed tissue is struggling to survive. 11. Stubborn bone infection (refractory osteomyelitis) that has not responded to usual treatment, used alongside standard care. 12. Sudden sensorineural hearing loss, an unexplained, rapid loss of hearing in one ear. 13. Severe anaemia from exceptional blood loss, in situations where a blood transfusion is not possible. 14. Acute thermal burn injury, serious burns treated as part of specialised care.

Several of these are emergencies handled directly through hospitals, such as carbon monoxide poisoning and decompression sickness. Others are planned treatments arranged through a referral. If your condition is on this list, HBOT may be a reasonable thing to discuss. If it is not on this list, that does not always mean the door is closed, but it does mean the evidence is weaker and the treatment is generally not publicly covered, which is exactly the kind of thing to talk through honestly with your doctor.

How to raise HBOT with your doctor

You do not need special language to bring this up. A simple opening works well: "I have been reading about hyperbaric oxygen therapy and I am wondering whether it is relevant to my condition. Can we talk about it?" Your doctor will not be offended by the question. Coming in with curiosity rather than a fixed conclusion tends to lead to the most useful conversation.

It helps to arrive prepared. Bring a short written summary of your diagnosis as you understand it, the treatments you have already tried, and what you are hoping HBOT might help with. If you found a specific claim online, bring the source so your doctor can look at it with you rather than guess at what you read. Be honest about your full health picture, including any lung or ear problems, recent surgeries, and all medications, because some of these affect whether HBOT is safe or suitable for you.

Remember that your family doctor or specialist may not be a hyperbaric expert, and that is normal. The realistic outcome of the conversation may be a referral to a hospital hyperbaric programme for a proper assessment, where a hyperbaric physician confirms whether the treatment is appropriate for you. That assessment is a feature, not a hurdle. It exists to make sure the treatment fits your actual condition.

Circular diagram called the informed decision loop with four stages: verify whether the condition is on the recognised Canadian list, assess the strength of the evidence, consult your doctor with your health history, and receive regulated care through a hospital assessment referral. — Figure Safe hyperbaric care follows a clear pathway rather than a search for the right clinic. The informed decision loop runs through four stages: verify whether your condition is one of the recognised Canadian indications, assess whether a claim is backed by trials rather than a single testimonial, consult your own doctor with your health history and questions, and access regulated, medical-grade treatment through a hospital assessment referral. A referral to a hyperbaric physician is a feature of that pathway, not a hurdle, because it confirms the treatment fits your actual condition.

Questions worth asking

A good conversation runs both ways. These questions help you understand where you stand and keep the discussion grounded in evidence rather than marketing:

Is my condition one of the recognised Canadian indications for HBOT? This tells you immediately whether you are talking about established care or an off-label use.
What would you realistically expect it to do for me? Ask for the likely benefit in plain terms, not a best-case story.
What does the evidence look like for my specific situation? Strong evidence for one condition does not transfer to another.
Would this be covered through a hospital programme, or only available privately at my own cost? Covered, hospital-delivered care and self-pay private care are very different situations.
What are the risks and who should not have HBOT? Every real treatment has limits and contraindications.
If it is not right for me, what are the better-supported options? A trustworthy answer often includes alternatives.
Can you refer me to a hospital hyperbaric programme for an assessment? This is the proper route for the recognised indications.

If a provider, anywhere, cannot or will not answer these questions clearly, treat that as useful information in itself.

Understanding the evidence

Good medical evidence is built in layers, and knowing the layers helps you judge any claim. The strongest evidence comes from well-run randomised controlled trials, where people are randomly assigned to receive a treatment or not, and from systematic reviews that pool many such trials together. Below that sit smaller controlled studies and consistent clinical experience. Weaker still are individual case reports, laboratory or mechanistic reasoning, and expert opinion. None of these are worthless, but a single dramatic story or an "it should work because" explanation is not the same as proof.

For HBOT, the strength of the evidence varies by condition, and that is one of the most important things to understand. Many of the fourteen recognised Canadian indications rest on higher-tier evidence, which is part of why they are recognised and covered. Carbon monoxide poisoning is one example: a randomised controlled trial published in the New England Journal of Medicine in 2002 reported fewer cognitive problems at six weeks in patients treated with HBOT compared with those given ordinary oxygen, and findings like this support the use of HBOT for serious cases. Even there, the broader research is not perfectly uniform, which is honest to acknowledge.

The key takeaway is that the evidence is not all-or-nothing across the board. HBOT being well supported for one condition tells you nothing about whether it works for another. When you see a claim, ask what condition it is actually about, what kind of study it comes from, and whether it has held up across more than one trial. Be cautious of language like "cure" or "proven to reverse," especially when the underlying support is a single small study or observations without a comparison group. Watching something improve in a group of patients does not, on its own, prove the treatment caused it.

Evidence pyramid ranking randomised controlled trials and systematic reviews at the top, smaller controlled studies and clinical experience in the middle, and individual case reports, personal stories and mechanistic reasoning at the base, with a carbon monoxide trial cited as an example of strong evidence. — Figure Medical evidence is built in layers. The strongest evidence comes from well-run randomised controlled trials and the systematic reviews that pool them; below sit smaller controlled studies and clinical experience; weakest are individual case reports, personal stories, and mechanistic reasoning. As an example of strong evidence, a randomised controlled trial published in the New England Journal of Medicine in 2002 reported fewer cognitive problems at six weeks in carbon monoxide poisoning patients treated with hyperbaric oxygen compared with ordinary oxygen. Evidence is not all-or-nothing: strong support for one condition does not transfer to another.

Spotting clinics that oversell

Most people offering HBOT are acting in good faith, and private clinics legitimately provide some services. The aim here is not suspicion of everyone but a few practical warning signs that something is being oversold.

Be cautious when you see any of the following:

A long list of conditions it supposedly treats. When a single therapy is marketed for autism, long COVID, anti-ageing, athletic recovery, and a range of unrelated problems at once, that breadth is a warning sign, not a selling point. These uses fall outside the recognised Canadian indications, which means the evidence for them is limited or unproven.
Guarantees, "cures," or dramatic before-and-after promises. Honest medicine deals in probabilities and limits, not guarantees.
Pressure to commit to many sessions and pay up front, often with package discounts that reward buying more.
Testimonials standing in for evidence. Personal stories are not the same as studies, and the most compelling stories are sometimes the least representative.
Vague or evasive answers about the equipment and pressure. Clinical HBOT uses medical-grade chambers at clinical pressures under qualified supervision. Soft, low-pressure inflatable chambers marketed for general wellness are a different thing, and the difference matters. It is reasonable to ask exactly what kind of chamber is used and at what pressure.
Discouraging you from talking to your own doctor. A trustworthy provider welcomes a second opinion and a referral conversation.

For the fourteen recognised conditions, treatment is generally available through hospital-based programmes. When delivered through a covered hospital programme with a valid provincial health card and a physician referral, it usually carries no out-of-pocket cost. That said, coverage and access vary across the country. Not every province has its own hospital programme, some refer patients to other provinces, and wait times can be long, so it is worth confirming the details for where you live. If you are being asked to pay privately for a condition that should be covered, or for a use that is not on the recognised list, slow down and bring it back to your doctor before committing.

Two-column comparison contrasting a recognised hospital programme, which keeps to the recognised conditions, uses medical-grade chambers, is publicly covered and requires a referral, with an overselling private clinic, which markets unrelated cures, is vague about equipment, pressures upfront payment, and relies on testimonials. — Figure A recognised hospital programme keeps to the recognised Canadian conditions, uses medical-grade chambers at clinical pressures, is publicly covered with a valid health card and referral, and requires a physician assessment. The warning signs of an overselling clinic are the opposite: a long list of unrelated cures such as autism, long COVID, or anti-ageing; vague answers about equipment, sometimes using soft low-pressure inflatable chambers; pressure to pay upfront for multi-session packages; and reliance on testimonials while discouraging a second opinion. Most providers act in good faith, so treat these as practical checks rather than blanket suspicion.

Where to learn more

You do not have to sort through all of this alone. The conditions section of this site explains each of the fourteen recognised Canadian indications in plain language, including what the evidence says and how care is delivered, so you can read up on your own situation before your appointment. The coverage section explains how public funding and referral work across the provinces and territories, what the difference is between covered hospital care and private self-pay treatment, and what to verify before paying for anything privately.

Use those pages to prepare, then bring your questions to your own doctor or to a hospital hyperbaric programme. This guide and this site are an independent Canadian resource meant to inform your conversation, not to replace medical advice. The best decision is one you and your healthcare team make together, with clear eyes and good information.

Signpost graphic pointing to three resources: plain-language breakdowns of the recognised indications, a coverage and access guide to provincial funding and wait times, and a research library of independent Canadian data. — Figure To prepare before an appointment, this site offers plain-language breakdowns of the science behind each recognised Canadian indication, a coverage and access guide explaining provincial funding rules, the difference between covered hospital care and private self-pay treatment, and wait times across the country, and a research library of independent Canadian data. Use these to prepare, then bring your questions to your own doctor or a hospital hyperbaric programme. The best decision is one you and your healthcare team make together.

Canada Hyperbarics, canadahyperbarics.ca. Reviewed each quarter. General patient information; not a substitute for the advice of the team treating you.