Frequently Asked Questions

Hyperbaric oxygen therapy (HBOT) is a medical treatment in which you breathe 100% oxygen inside a pressurized chamber. The combination of increased pressure and pure oxygen dramatically raises the amount of oxygen your blood can carry, allowing oxygen to reach tissues that may be poorly perfused. It is used for specific medical conditions where this increased oxygen delivery supports healing or treats the underlying problem.

At normal atmospheric pressure, most oxygen in your blood is carried by hemoglobin in red blood cells. Under hyperbaric conditions, a much larger amount of oxygen dissolves directly into the plasma (the liquid part of your blood). This dissolved oxygen can reach tissues that red cells cannot fully supply — including damaged, infected, or poorly perfused areas — and supports a range of healing mechanisms including new blood vessel formation, antimicrobial activity, and reduced tissue swelling.

Hyperbaric oxygen therapy is a recognized medical treatment for specific indications. Hyperbaric chambers are licensed medical devices in Canada. The Ontario Health Insurance Plan (OHIP) covers HBOT for 9 specific conditions that Evolve treats. A physician referral is preferred but not required — patients can self-refer, and our hyperbaric physicians can assess eligibility directly.

A typical session involves about 10 minutes of compression, 60 to 90 minutes at treatment pressure, and about 10 minutes of decompression. Plan for approximately 2 hours at the clinic from arrival to departure.

It depends on your condition. Sudden sensorineural hearing loss typically uses 20 sessions. Diabetic foot ulcers and radiation injury typically use 30 to 40. Crush injury and compromised graft cases may be shorter (10 to 20). Your hyperbaric physician will explain the recommended course for your specific situation.

HBOT has a very strong safety profile when delivered under physician supervision in a properly maintained facility. Serious complications are rare. The most common side effects are minor and usually manageable — middle ear discomfort being the most frequent. See What to Expect for a detailed discussion of safety and side effects.

The most common are middle ear discomfort or barotrauma (managed with ear-clearing techniques and slower compression), temporary visual changes (mild and reversible), and occasional fatigue. Less common effects include claustrophobia and, very rarely, oxygen toxicity seizures.

Each of our chambers is a monoplace unit — meaning one patient per chamber. However, you are never alone in the sense that matters: our trained staff are with you the entire time, monitoring your status, communicating with you, and able to respond immediately to anything you need.

Many patients have some initial concern about the enclosed chamber. We address this by giving you a thorough orientation before your first session, letting you sit in the chamber before treatment starts, talking with you throughout sessions, and pacing compression so you can adjust gradually. Most patients adapt quickly. If anxiety is significant, your physician may recommend anxiolytic medication for the first few sessions.

No personal electronics, phones, or lighters can come into the chamber for fire safety reasons. We have entertainment systems for movies and audio. Books are generally not permitted in the chamber but you can watch reading material on screen.

No. Soft-sided chambers used in some wellness settings operate at pressures of approximately 1.3 ATA on air (not pure oxygen). These do not deliver the oxygen tensions required for the medical indications we treat. Evolve uses Perry Baromedical hard-shell monoplace chambers rated for 2.0–3.0 ATA with 100% oxygen — the only configuration appropriate for medical HBOT.

Yes — for 9 specific conditions, OHIP covers HBOT in full. Eligible Ontario residents with a valid health card and a qualifying diagnosis pay nothing for treatment. A physician referral is preferred (it speeds the process and helps us coordinate with your care team), but not required — patients can self-refer through our Check Eligibility form. If you don’t have a referring physician, we assess you and connect you with the relevant doctors. See OHIP coverage for the list and details.

Off-label indications (post-concussion symptoms, long COVID, inflammatory bowel disease, orthopedic non-union, selected post-surgical recovery) are not OHIP-covered. We offer these on a private-pay basis. Some private extended-health-benefit plans cover hyperbaric therapy — verify with your insurer.

Some Canadian extended-health-benefit plans cover hyperbaric therapy, particularly for off-label indications, but coverage varies widely. We provide receipts for plans that cover HBOT. We recommend you call your insurer in advance with the specific indication.

WSIB (Workplace Safety and Insurance Board) covers HBOT for selected work-related injuries that align with the OHIP-covered indications. See WSIB coverage.

For OHIP-covered indications, we bill OHIP directly — there is no out-of-pocket cost for the treatment itself. For off-label indications, you pay directly and we provide receipts for insurance submission.

See OHIP-covered conditions for the chronic indications Evolve treats, and off-label indications for the private-pay conditions we offer.

No. HBOT is not a cancer treatment. It is used after cancer treatment for specific late effects — most notably late radiation tissue injury, which is one of the OHIP-covered indications.

These are not indications we treat at Evolve. While there is some recent academic interest in the biological effects of HBOT in healthy individuals, the evidence does not support routine use for anti-aging or performance, and these uses are not within our clinical scope.

Children can receive HBOT for the OHIP-covered indications when clinically appropriate. Pediatric protocols may differ. We assess each case individually and coordinate with the child’s specialist team.

We provide 100% cotton clothing for treatment. You should not wear synthetic fabrics, oil-based skin products, makeup, hair products, or perfume into the chamber. Our staff will guide you.

Yes — eat normally. Stay hydrated. Avoid alcohol and tobacco for at least 8 hours before treatment.

Yes, most patients drive themselves to and from sessions without issue. Some report mild fatigue, particularly early in a course; if you feel tired, give yourself a moment before driving.

Some patients experience a temporary mild change in near vision (myopic shift) during longer courses. This typically returns to baseline within weeks of completing therapy. Your hearing should not change other than the expected ear-pressure sensations during compression and decompression.

A physician referral is preferred but not required, whether the indication is OHIP-covered or off-label. You can submit a Check Eligibility request through our contact page directly, and our team will work with you (and, if you have one, your physician) to coordinate.

Most non-urgent consultations are scheduled within 1 to 2 weeks. Time-sensitive presentations — sudden sensorineural hearing loss within 14 days of onset, a recently compromised graft or flap, or a wound at risk of significant deterioration — are scheduled same-day or next-day where clinically appropriate.

Yes. We have six locations across Ontario. Most patients choose the closest one, but some prefer a different location for scheduling reasons. We will work with you.

For OHIP-covered indications, treatment typically begins within 1 to 2 weeks of the consultation. For urgent conditions, sometimes the same day.

You receive a discharge summary, and a copy is sent to your referring physician. Ongoing care is generally arranged through your referring physician.

Any Ontario-licensed physician can refer you for HBOT. Most referrals come from family physicians, specialists in the relevant condition area (wound care, vascular surgery, radiation oncology, ENT, etc.), and emergency departments.

No — OHIP-covered HBOT requires a physician referral. For private-pay off-label consultations, you can contact us directly, although we still recommend involving your family physician for coordinated care.

That is very common. We are happy to speak with your physician directly to discuss whether HBOT may be appropriate for your condition. Have your physician call 1-888-851-4268.

See our eligibility page for a discussion of absolute and relative contraindications. The only universally absolute contraindication is untreated pneumothorax. Many relative contraindications can be managed with careful planning.