Updated July 27, 2026. Research on hyperbaric oxygen therapy (HBOT) for post-COVID condition is still developing, and the published findings are mixed. This evidence review separates what individual trials reported from what buyers should conclude about a specific chamber.
Short answer
HBOT should not be presented as a proven cure for Long COVID. A 2022 randomized, sham-controlled study of 73 participants reported improvements after a 40-session medical protocol, but two later randomized controlled trials using 10-session protocols found no significant advantage over sham or lower-dose comparison groups on their main outcomes. These studies used supervised research protocols and do not establish that a consumer or commercial chamber will produce the same result.
What the main randomized studies found
2022: a 40-session trial reported benefits
A randomized, sham-controlled, double-blind study published in Scientific Reports enrolled 73 people with persistent post-COVID symptoms. Participants were assigned to 40 daily HBOT sessions or sham treatment. The authors reported improvements in several neurocognitive and symptom measures in the HBOT group. This was an important early trial, but it was relatively small and tested a specific clinical protocol rather than an equipment brand.
2025: HOT-LoCO found no significant short-term benefit over placebo
The HOT-LoCO phase II trial randomized 80 participants to 10 HBOT or sham sessions over six weeks. At 13 weeks, both groups improved, but the investigators found no significant between-group difference in the two primary RAND-36 outcomes. The result does not prove that every possible protocol is ineffective; it shows that the tested 10-session protocol did not outperform placebo on its primary endpoints.
2025: a four-group oxygen and pressure trial also found no significant effect
A separate randomized study of 101 participants compared different combinations of oxygen concentration and chamber pressure. Investigators reported no significant differences between groups in subjective symptoms, functional scores, or cognitive performance. They concluded that claims of a significant Long COVID effect require more investigation before broad promotion.
Why the results cannot be treated as interchangeable
The trials differed in session count, pressure, oxygen exposure, participant selection, endpoints, and follow-up. A positive result under one protocol cannot be transferred automatically to another protocol, a different patient group, or a different chamber. Pressure labels alone do not establish a clinical effect, biological mechanism, or treatment outcome.
What this means for O2BAY buyers
O2BAY supplies hyperbaric chamber equipment. Product pages should be evaluated using model-specific engineering and procurement evidence: pressure-control range, oxygen-delivery configuration, electrical requirements, safety systems, operating instructions, training, maintenance, installation planning, warranty, and destination-market documentation. Equipment specifications are not evidence of clinical effectiveness for a disease.
- Ask for the exact model and configuration sheet.
- Confirm whether oxygen is delivered by mask or headset and verify the concentrator specification.
- Review pressure-control, ventilation, emergency-release, grounding, cleaning, and maintenance instructions.
- Confirm who will operate and supervise the equipment and what local rules apply.
- Do not rely on testimonials, unsupported medical labels, or guaranteed outcome claims.
Safety context
In an August 25, 2025 safety letter, the U.S. Food and Drug Administration reminded health care providers and facilities to follow device instructions, maintain fire-prevention and grounding measures, provide staff training, supervise users, and complete recommended cleaning, maintenance, and safety checks. The FDA also noted reports of serious injuries and deaths involving HBOT devices, including fires, while describing serious adverse events as rare.
Anyone considering HBOT for symptoms should discuss the evidence, contraindications, and alternatives with a qualified health professional. This article is an evidence summary, not medical advice, a diagnosis, or a treatment recommendation.
Primary and authoritative sources
- Scientific Reports (2022): randomized sham-controlled trial, 40-session protocol
- BMJ Open (2025): HOT-LoCO randomized placebo-controlled phase II trial
- PubMed (2025): randomized trial comparing oxygen and pressure modalities
- ClinicalTrials.gov: ongoing HBOT post-COVID study record
- FDA (2025): safe use of HBOT devices
Related buyer resources
For equipment due diligence, use the O2BAY manufacturer facts and buyer evidence and the hyperbaric chamber manufacturer verification checklist.