HBOT and Fibromyalgia: Promising Trials That Still Need Replication
Israeli randomized trials report symptom relief and brain-imaging changes in fibromyalgia, especially after trauma. The results are encouraging but single-center and small.
- A 2015 PLOS ONE trial of 60 women with fibromyalgia reported significant improvements on measures such as the Fibromyalgia Impact Questionnaire after 60 HBOT sessions.
- Using SPECT scans, researchers reported that clinical improvement corresponded with measurable changes in brain regions involved in processing pain.
- Most of this evidence comes from a single research center with modest participant numbers, has not been independently replicated at scale, and remains investigational.
The trials that put HBOT on the map for fibromyalgia
Fibromyalgia is a chronic condition marked by widespread pain, fatigue and cognitive difficulty, and it remains hard to treat. A cluster of studies from Shai Efrati and colleagues in Israel has explored whether HBOT can help. The best known is a 2015 randomized trial published in PLOS ONE, which enrolled 60 women with fibromyalgia and assigned them to 60 HBOT sessions or to a waiting-list control that later crossed over to receive the same treatment. The treated participants showed significant improvements in standard fibromyalgia measures, including the Fibromyalgia Impact Questionnaire, tender-point counts and pain thresholds.
The protocol in these trials was intensive: typically 60 daily sessions breathing high-concentration oxygen at around 2 atmospheres absolute, a far more demanding course than a handful of casual wellness visits. That intensity is one reason the results are hard to generalize to lighter, everyday use.
What the brain imaging showed
What made the study notable was not only the symptom scores but the imaging. Using SPECT brain scans, the researchers reported that clinical improvement corresponded with measurable changes in brain activity in regions involved in processing and modulating pain. The authors interpreted this as evidence that HBOT was acting on the central nervous system rather than producing a purely subjective effect, and they framed fibromyalgia partly as a condition of disturbed brain function.
The post-trauma subgroup
Later work narrowed in on patients whose fibromyalgia was linked to earlier trauma. A trial focused on women with a history of childhood sexual abuse, again using a crossover design, reported improvements in symptoms, quality of life and post-traumatic stress measures, alongside changes on SPECT and MRI imaging. A further randomized study compared HBOT with drug treatment in fibromyalgia patients who had also suffered a traumatic brain injury. Across these studies the post-trauma subgroup has appeared to respond, which the researchers read as a clue to who might benefit most.
Why caution is still warranted
The consistent limitation is that most of this evidence comes from a single research center, with modest numbers of participants and designs that are hard to blind, since patients generally know whether they are being pressurized. Independent teams have not yet replicated the results at scale, and fibromyalgia itself has few reliably effective treatments, which raises both the appeal of any positive result and the risk of reading too much into early data. Readers comparing the pressurized, high-oxygen setups used in these trials with what is sold commercially should note that the protocols typically relied on clinical-grade equipment; our page on monoplace chambers (monoplace chambers) explains how those systems differ from lighter consumer models.
The fibromyalgia research is among the more intriguing HBOT signals, but intriguing is not the same as proven. Until larger, multi-center trials confirm the effect, HBOT for fibromyalgia remains investigational. Anyone living with the condition should treat it as an option to explore with a qualified physician, not as a settled therapy.
Frequently asked questions
+Does HBOT help fibromyalgia symptoms?
A 2015 randomized trial of 60 women reported significant improvements in standard fibromyalgia measures - including the Fibromyalgia Impact Questionnaire, tender-point counts and pain thresholds - after a course of 60 HBOT sessions. The protocol was intensive. However, until larger, multi-center trials confirm the effect, HBOT for fibromyalgia remains investigational, so treat it as an option to explore with a physician.
+What did the brain imaging in the fibromyalgia trials show?
Using SPECT brain scans, the researchers reported that clinical improvement corresponded with measurable changes in brain activity in regions involved in processing and modulating pain. They interpreted this as evidence that HBOT was acting on the central nervous system rather than producing a purely subjective effect, and framed fibromyalgia partly as a condition of disturbed brain function.
+Is the fibromyalgia evidence strong enough to rely on?
Not yet. The consistent limitation is that most of this evidence comes from a single research center, with modest participant numbers and designs that are hard to blind, since patients generally know whether they are being pressurized. Independent teams have not replicated the results at scale, so HBOT for fibromyalgia remains investigational rather than proven.