HBOT for PTSD has been studied primarily in military veteran populations with comorbid TBI. Results suggest meaningful symptom reduction in patients who have the TBI/PTSD overlap, though isolating HBOT's effect on pure PTSD without TBI remains difficult. The Harch group has published multiple small trials.
How HBOT Works
Hypothesised mechanisms include reduction of neuroinflammation (implicated in both TBI and PTSD), improved cerebral perfusion in previously hypoperfused brain regions, and effects on hippocampal volume and function. The exact mechanism in PTSD specifically — as distinct from the TBI effect — is unclear.
Clinical Protocol
Typical protocol
40 sessions at 1.5–2.0 ATA
Evidence level
Early-phase trials — Limited evidence
FDA / regulatory status
Not FDA-approved
Protocols vary. Harch-group trials have used both 1.5 ATA and 2.0 ATA with 40-session courses. The 2.0 ATA Efrati-aligned protocols are increasingly favoured for the overlap TBI/PTSD population.
Cautions & Considerations
HBOT does not replace trauma-focused psychotherapy or SSRIs/SNRIs.
Evidence base is limited; much data comes from TBI/PTSD overlap populations.
Not FDA-approved; usually cash-pay or specific state programmes for veterans.