Frequently Asked Questions

HBOT is a medical treatment in which a patient breathes 100% oxygen inside a chamber pressurised above sea-level atmospheric pressure. The elevated pressure dissolves additional oxygen directly into blood plasma, driving tissue oxygenation at levels unachievable at normal atmospheric pressure.

The UHMS clinical standard for most medical indications is 2.4 ATA (atmospheres absolute). Neurological research protocols typically use 2.0 ATA, and emergency indications such as carbon monoxide poisoning or decompression sickness use 2.8–3.0 ATA.

A monoplace chamber treats one patient at a time, is pressurised with 100% oxygen, and is the dominant configuration in US hospital HBOT. A multiplace chamber is a large steel vessel pressurised with air that treats multiple patients simultaneously via masks or hoods, with medical staff able to attend inside the chamber.

Mild HBOT refers to treatment at 1.3 ATA using soft-shell portable chambers, typically with 85–95% oxygen via concentrator. The FDA has cleared 1.3 ATA chambers only for altitude sickness. Use for other indications is off-label and the clinical evidence base is weaker than for 2.0+ ATA protocols.

A standard neurological course is 40 sessions over 8 weeks (five days a week). Wound care courses typically run 20–40 sessions. Emergency indications (DCS, CO) may require only 1–5 sessions. Each session typically lasts 90 minutes including air breaks.

The 14 UHMS-approved indications include: decompression sickness, arterial gas embolism, carbon monoxide poisoning, clostridial myonecrosis, crush injury, decompression illness, exceptional blood loss anaemia, intracranial abscess, necrotising soft-tissue infection, osteomyelitis (refractory), delayed radiation injury, compromised skin grafts and flaps, thermal burns, and sudden sensorineural hearing loss.

HBOT is not FDA-approved for these neurological indications, so treatment is off-label. However, a growing body of RCT evidence — particularly from the Efrati lab in Tel Aviv — supports clinical benefit at 2.0 ATA for mild-to-moderate TBI, chronic stroke recovery, and long COVID brain fog. Most patients pay out of pocket.

HBOT has an excellent safety profile when administered by trained staff with proper screening. The most common side effect is middle-ear barotrauma, which is why ear equalisation is screened before treatment. Rare but serious adverse events include oxygen toxicity seizures and pneumothorax. Pre-treatment screening and in-chamber air breaks mitigate both.

Absolute contraindications include untreated pneumothorax. Relative contraindications include recent eye surgery, severe COPD with air trapping, uncontrolled epilepsy, uncontrolled fever, severe claustrophobia, and some chemotherapy agents (bleomycin, doxorubicin). All candidates should have a hyperbaric physician review their medical history before initiating treatment.

US out-of-pocket cost per session typically ranges from $150 to $450. A full 40-session neurological course can therefore run $6,000–$18,000. UHMS-approved indications in US hospital facilities are generally reimbursed by Medicare and most private insurers at around $450 per session.

Soft-shell 1.3 ATA chambers are FDA-cleared only for altitude sickness. Many patients use them off-label for wellness and recovery, but the clinical evidence at 1.3 ATA is weaker and insufficient for UHMS-approved emergency indications. Home use requires careful attention to safety (no open flames, no electronics inside, trained operator for pressurisation).

Central nervous system (CNS) oxygen toxicity is a rare seizure risk at pressures above 2.0 ATA with 100% O₂. It is prevented by using 5-minute "air breaks" every 20–30 minutes of oxygen breathing during longer sessions. Pulmonary oxygen toxicity is a cumulative effect from prolonged high-FiO₂ exposure and is rarely relevant to standard HBOT courses.

HBOT is routinely combined with wound-care interventions (debridement, offloading, antibiotic therapy) and with physical therapy for neurological indications. Some chemotherapy agents (bleomycin, doxorubicin) are contraindications. Always coordinate HBOT with the full medical team.

Multiple randomised controlled trials from the Efrati lab (Hadanny & Efrati 2020, Tal et al. 2017) have shown significant cognitive improvement in mild-to-moderate TBI patients treated with 40–60 sessions at 2.0 ATA, including chronic cases years after the injury. The evidence is considered moderate overall and remains outside FDA approval.

In the US, Medicare and most private insurers cover HBOT for the 14 UHMS-approved indications at a hospital-based hyperbaric facility, typically at 2.4 ATA. Off-label use for TBI, stroke, long COVID, and other research-stage indications is almost always paid out of pocket.