Mild Hyperbaric Oxygen Therapy (mHBOT) and Concussion: What the Evidence Says

Who this is for: Patients researching options, providers fielding questions about mHBOT, and attorneys who see it in a treatment plan. Braintree Health Partners provides diagnostics only. We do not recommend or provide this therapy as part of our testing service.

Interest in hyperbaric oxygen after brain injury has grown, and "mild" versions are widely marketed. Because patients ask us about it, this article lays out the evidence plainly. It is education, not a recommendation.

What "mild" hyperbaric means

Hyperbaric oxygen therapy involves breathing oxygen in a chamber pressurized above normal atmospheric pressure. The Undersea and Hyperbaric Medical Society describes clinical HBOT as near-100% oxygen at a pressure of at least 1.4 atmospheres absolute. "Mild" hyperbaric typically refers to lower pressures, often around 1.3 atmospheres, sometimes with room air or added oxygen. That difference matters, because study results at one pressure do not automatically apply to another.

Regulatory status

The FDA has cleared hyperbaric chambers for a defined list of conditions, such as decompression sickness. According to a 2025 Department of Defense information paper, the FDA has not cleared HBOT for TBI or post-concussion symptoms. The Undersea and Hyperbaric Medical Society currently considers HBOT for brain injury investigational.

What research has found

• Sham-controlled trials. A 2015 randomized trial in service members with persistent post-concussion symptoms compared hyperbaric oxygen with a sham chamber and with usual care. Both chamber groups improved more than usual care alone, but the oxygen group did not clearly outperform the sham group.
• Mixed reviews. A 2022 systematic review of HBOT for persistent post-concussion symptoms reported favorable findings at some pressures, but also found both positive and negative results at mild-hyperbaric pressures, with small studies throughout.
• Durability. The Department of Defense summary notes that improvements seen in some studies tended to fade over months of follow-up.

The fairest summary today: an area of active research, with mixed and emerging evidence and no FDA clearance for concussion.

Where diagnostics fit

Whatever a treating provider considers, clear baseline information helps. Braintree's role is documentation: physician-reviewed diagnostic reports, including eye-movement and neurocognitive measures, sent to a neurologist who interprets them, with a copy to the referring provider. Those findings can help the provider track how a patient is doing over time, whatever care plan they choose. Learn more about coordinating care after a TBI diagnosis. We diagnose. You treat.

For patients: questions to ask

• What pressure and oxygen level will be used, and what research supports that setup?
• Who supervises sessions, and is the facility accredited?
• What are the risks for me, including ear pressure and any conditions that make it unsafe?
• How will we measure whether it is helping?

For providers and attorneys

When mHBOT appears in a plan, it should be documented as a provider's clinical choice with its investigational status noted. Avoid describing outcomes as expected or guaranteed. Our provider and attorney pages explain how diagnostic reports are delivered.