Strong evidence· Points toward a benefit
HBOT (hard, 2.8 ATA / US Navy Table 6) is the definitive, standard-of-care treatment for decompression sickness; delays in reaching a chamber worsen outcomes.
Studied in Divers, aviators, compressed-air workersexpert opinion
How strong the finding is
UHMS consensus; no RCT possible (ethical); extensive case series. Source: UHMS HBO indications. Dossier claim id hbot-h01. ATA 2.8 (HARD). NOTE: hard-HBOT; mild HBOT runs 1.3-1.5 ATA.
What complicates this
Hard-chamber emergency indication; outside mild-HBOT scope.
Moderate evidence· Points toward a benefit
HBOT (1.5–2.0 ATA, 40–60 sessions) shows significant CAPS-5 PTSD reductions in sham-controlled RCTs; the effect is threshold-dependent (>=35% symptom reduction predicts sustained benefit at 2 years).
Studied in Military veterans with combat PTSD (largely male)clinical studies
How strong the finding is
Frontiers Neurology 2024 SR PMC11179433 (8 studies, n=393, 7 RCTs); sham-controlled RCT 2024 (J Clin Psychiatry, 56 male veterans). Source: PMC11179433. ATA 1.5-2.0 (HARD).
What complicates this
Largely male veteran population; generalizing to civilian/female wellness requires caution.
Moderate evidence· Points toward a benefit
HBOT (1.5–2.4 ATA, 10–40 sessions) significantly reduces pain intensity and improves QoL in chronic non-cancer pain vs. control; strongest in fibromyalgia and neuropathic pain.
Studied in Adults with chronic non-cancer painclinical studies
How strong the finding is
Dove Medical Press / J Pain Research 2025 SR PMC13033199. Source: PMC13033199. Dossier claim id hbot-h16. ATA 1.5-2.4 (HARD).
What complicates this
Strongest in fibromyalgia subset; hard-HBOT pressures.
Moderate evidence· Points toward a benefit
HBOT (2.0 ATA, 40 sessions) improves fatigue, cognitive function, QoL, and cardiopulmonary function in long COVID, consistent across a systematic review and a large prospective registry.
Studied in Adults with long COVID (post-acute sequelae SARS-CoV-2)clinical studies
How strong the finding is
MDPI Life 2024 SR PMC11051078 (10 studies, 3 complete RCTs); Nature Sci Reports 2025 registry n=232. Source: PMC11051078. Dossier claim id hbot-h15. ATA 2.0 (HARD).
What complicates this
Evidence growing; one interim RCT logged 60% AE rate (mostly mild ear discomfort). Condition-specific at 2.0 ATA.
Moderate evidence· Points toward a benefit
HBOT (2.0–2.4 ATA, 20–40 sessions) improves healing of radiation-injured tissue by stimulating angiogenesis in the avascular post-radiation wound; UHMS-approved indication.
Studied in Adults undergoing surgery in previously irradiated tissue (head/neck, pelvis)clinical studies
How strong the finding is
UHMS consensus; multiple case series and prospective cohorts; limited RCTs. Source: UHMS HBO indications. Dossier claim id hbot-h04. ATA 2.0-2.4 (HARD).
What complicates this
Limited RCTs; hard-HBOT indication.
Moderate evidence· Mixed findings
HBOT (1.5–2.4 ATA, 5–10 sessions) significantly reduces objective muscle-injury markers (CK; p<0.0001) but does NOT reduce subjective soreness vs. control.
Studied in Athletes and active adultsclinical studies
How strong the finding is
2025 systematic review & meta-analysis, 10 studies, n=299; PMID 40784513. Source: PMID 40784513. Dossier claim id hbot-h05. ATA 1.5-2.4 (HARD).
What complicates this
Soreness (DOMS) null even at hard pressures — do not market HBOT for soreness relief. Distinct from h06 (performance null).
Moderate evidence· Mixed findings
HBOT (2.0 ATA, 20–40 sessions) improves post-stroke depression response rates (69.4% vs. 51.2%, OR=2.51) and general neurological function (NIHSS); cognitive outcomes are inconsistent.
Studied in Adults with ischemic stroke / post-stroke sequelaeclinical studies
How strong the finding is
Liang et al. 2020 (PMID 32474256, Clin Neurol Neurosurg), meta-analysis of 27 RCTs, n=2,250, post-stroke depression: HBOT response rate 69.4% vs. 51.2% control (OR=2.51, 95% CI 1.83-3.43), reduced NIHSS (WMD=-2.77). PMC8888529 (cognitive SR); PMC12173912 (2025 bibliometric). Dossier claim id hbot-h10. ATA 2.0 (HARD).
What complicates this
Cognitive outcomes inconsistent; 2022 SR called for standardized protocols.
Moderate evidence· Points toward a benefit
HBOT (2.0 ATA, 30–40 sessions) significantly reduces tender point count, VAS pain, and FIQ and improves sleep/QoL in fibromyalgia; two separate meta-analyses show consistent benefit sustained at 3-month follow-up.
Studied in Adults with fibromyalgia (predominantly female)clinical studies
How strong the finding is
PMC10204569 meta-analysis 2023 (4 RCTs, n=163); 2024 LWW analysis (5 RCTs, n=180). Source: PMC10204569. Dossier claim id hbot-h14. ATA 2.0 (HARD). Most consistent wellness-adjacent finding.
What complicates this
Condition-specific; does not generalize to healthy adults for pain prevention. Evidence at 2.0 ATA hard chamber.
Moderate evidence· Points toward a benefit
HBOT (2.0 ATA, 40 sessions) significantly improves neurocognitive deficits vs. baseline in TBI; a moderate-TBI RCT showed improved GCS at 10 days at 1.4 ATA. Attention and processing speed show the largest effect sizes (0.74–0.79).
Studied in Adults with mild-to-moderate TBI; military veteransclinical studies
How strong the finding is
Neurology meta-analysis (Borg) 4 studies n=250; RCT PMC11875703 (moderate TBI, 1.4 ATA, n=56); SR PMC8968958. Source: Neurology DOI 10.1212/WNL.0000000000211724. Dossier claim id hbot-h08. ATA 1.4-2.4 (HARD).
What complicates this
Most positive data at hard pressures (1.4-2.4 ATA); increased CNS O2 toxicity risk above 2.4 ATA.
Moderate evidence· Mixed findings
HBOT (2.0–2.4 ATA, 20–40 sessions) as adjunct to standard wound care improves short-term complete healing and reduces major amputation in refractory diabetic foot ulcers; the Cochrane review found short-term but not 12-month amputation benefit.
Studied in Adults with diabetic foot ulcers refractory to 30+ days standard careclinical studies
How strong the finding is
PMC11890413 2025 (14 studies, n=768); Cochrane (Kranke). Source: PMC11890413. Dossier claim id hbot-h03. ATA 2.0-2.4 (HARD).
What complicates this
Benefit short-term; long-term amputation reduction not confirmed in Cochrane. NNT ~6 for amputation prevention.
Moderate evidence· Points toward a benefit
HBOT (hard, 2.4–3.0 ATA) significantly reduces delayed neurological syndrome vs. normobaric O2 in carbon monoxide poisoning (DNS 32% to 19% in Weaver 2002); benefit strongest in high-risk patients.
Studied in Adults with moderate/severe CO poisoning; pregnancyclinical studies
How strong the finding is
Cochrane (Buckley); Weaver RCT n=152, JAMA 2002. Source: NBK459172. Dossier claim id hbot-h02. ATA 2.4-3.0 (HARD).
What complicates this
Some RCTs null on DNS prevention; meta-analysis favors HBOT for high-risk. Hard-HBOT indication.
