When a 37-year-old woman with antiphospholipid syndrome developed sudden facial paralysis two weeks after childbirth, standard treatment offered little relief. Despite high-dose corticosteroids, her Bell’s palsy persisted—until clinicians tried hyperbaric oxygen therapy. After just one session, improvement was visible. By the twelfth treatment, symptoms had resolved completely.
This case, reported in March 2026 in Frontiers in Rehabilitation Sciences, joins a growing body of literature exploring HBOT’s potential role in treating acute peripheral facial paralysis. Yet the therapy remains outside FDA-cleared indications, leaving clinicians and patients to navigate uncertain terrain between emerging evidence and established regulatory boundaries.
Understanding Bell’s Palsy and Its Challenges
Bell’s palsy affects approximately 11 to 40 people per 100,000 annually, making it the most common cause of acute facial nerve paralysis. The condition strikes suddenly, often overnight, leaving patients with unilateral facial weakness that can impair eye closure, speech, eating, and emotional expression. While roughly 70 percent of cases resolve spontaneously, the remaining 30 percent face residual weakness, synkinesis (involuntary linked movements), and lasting functional or aesthetic deficits.
The pathophysiology remains incompletely understood. Leading theories include viral reactivation—particularly herpes simplex virus—autoimmune mechanisms, and ischemia of the facial nerve’s delicate microvasculature. This vascular hypothesis has particular relevance to HBOT, which fundamentally works by delivering supraphysiological oxygen levels to compromised tissues.
Pregnancy and the postpartum period present unique vulnerabilities. Women during this time experience fluid retention, hormonal fluctuations, immune modulation, and hypercoagulability—factors that can compress the facial nerve or compromise its blood supply through the vasa nervorum. Recovery rates in pregnant and postpartum women lag significantly behind the general population: approximately 52 percent versus 77 to 88 percent.
The 2026 Case: HBOT After Steroid Failure
The recent Israeli case report describes a complex presentation that tested conventional approaches. The patient, diagnosed with antiphospholipid syndrome—a autoimmune disorder characterized by thrombosis risk—developed complete unilateral facial paralysis two weeks postpartum. Standard treatment with 60 mg daily of prednisone produced no clinical improvement after several days.
Clinicians at Shamir Medical Center’s Sagol Center for Hyperbaric Medicine and Research initiated HBOT at 2.0 atmospheres absolute, administering 20 sessions over four weeks. The response was striking: noticeable improvement after the first session, progressive recovery throughout treatment, and complete resolution by session twelve.
What distinguished this case extended beyond motor recovery. The patient’s anti-dsDNA antibodies, elevated during pregnancy, normalized following HBOT—a finding that hints at potential immunomodulatory effects warranting further investigation.
A Growing Pattern: The 2025 Case Series
The Israeli report builds upon earlier evidence published in 2025. A case series from the Journal of Family Medicine and Primary Care documented HBOT’s effectiveness as adjunctive therapy in Bell’s palsy patients treated at a tertiary care center in India.
That series, while limited by small sample size and lack of randomization, found that patients receiving HBOT alongside standard medical management showed enhanced recovery compared to historical controls receiving steroids alone. The authors concluded that HBOT “can be considered as an effective adjuvant therapy” particularly for patients with severe presentations or risk factors for poor recovery.
The mechanistic rationale centers on HBOT’s ability to address the ischemic component of facial nerve injury. By delivering oxygen at pressures typically twice atmospheric levels, HBOT dissolves oxygen directly into plasma, achieving tissue oxygen levels impossible under normal conditions. This hyperoxygenation can rescue ischemic neurons, reduce edema, suppress inflammatory cascades, and promote angiogenesis—all processes relevant to facial nerve recovery.
Animal studies have provided supportive evidence. Research on facial nerve injury models demonstrates that HBOT, particularly when combined with corticosteroids, reduces axonal degeneration, prevents vascular obstruction, and increases axonal diameter compared to either treatment alone. These findings suggest potential synergy between the anti-inflammatory effects of steroids and the tissue-level benefits of hyperoxygenation.
The Evidence Gap: What We Don’t Know
Despite these promising observations, the evidentiary foundation for HBOT in Bell’s palsy remains thin. The 2026 case report represents a single patient with unique complicating factors—postpartum status and antiphospholipid syndrome—that limit generalizability. The 2025 case series, while valuable, lacked control groups, randomization, and blinding—methodological features essential for establishing causal efficacy.
No randomized controlled trials have specifically examined HBOT for Bell’s palsy in the modern era. The only prior trial, published in Undersea and Hyperbaric Medicine in 1997, was small and produced inconclusive results that have limited influence on current practice.
This evidence gap has direct regulatory implications. The FDA has not cleared HBOT for Bell’s palsy or any form of peripheral facial paralysis. The agency’s cleared indications remain limited to fourteen conditions—including decompression sickness, carbon monoxide poisoning, certain non-healing wounds, and radiation tissue injury—none of which encompass neurological conditions like Bell’s palsy.
FDA Position: Caution on Unproven Uses
The FDA’s consumer guidance on hyperbaric oxygen therapy explicitly warns against using the treatment for conditions lacking cleared indications. The agency notes that while HBOT is “generally covered by insurance” for approved uses, off-label applications require careful consideration of risk-benefit profiles.
This regulatory positioning carries practical weight. Without FDA clearance, insurance coverage for HBOT in Bell’s palsy is unlikely, leaving patients to pay out-of-pocket for treatments that typically cost several hundred dollars per session. A standard course of 10 to 20 sessions can exceed $5,000 to $10,000—expenditure justified only by convincing evidence of benefit.
The FDA’s 2025 safety letter to healthcare providers adds another layer of consideration. The agency warned of fire risks, injuries, and deaths associated with HBOT devices, emphasizing the importance of proper protocols, trained personnel, and accredited facilities. For patients considering off-label HBOT, these safety concerns underscore the importance of seeking treatment at established hyperbaric centers rather than unregulated wellness facilities.
Clinical Implications and Future Directions
Where does this leave clinicians managing Bell’s palsy patients? Current guidelines from professional societies continue to emphasize corticosteroids as first-line therapy, ideally initiated within 72 hours of symptom onset. Antiviral medications remain controversial, with evidence supporting their use in severe cases at most.
HBOT’s potential role appears strongest as adjunctive therapy for patients with severe presentations, poor prognostic factors, or inadequate response to steroids. The postpartum population, with their elevated risk and reduced spontaneous recovery rates, may represent a particularly appropriate candidate group—though this hypothesis awaits formal testing.
The facial nerve’s unique anatomical vulnerability supports continued investigation. Compressed within the narrow fallopian canal at the skull base, the nerve has limited capacity to accommodate inflammatory edema. Any intervention that reduces tissue swelling or improves microvascular perfusion could theoretically prevent the irreversible axonal damage responsible for permanent weakness.
A Call for Rigorous Study
The convergence of biological plausibility, preliminary clinical evidence, and persistent unmet need suggests HBOT for Bell’s palsy deserves more rigorous investigation. A well-designed randomized controlled trial comparing steroid therapy with and without HBOT augmentation could clarify whether the promising case reports reflect true therapeutic benefit or placebo effects and natural history.
Such research would need to address key questions: optimal timing of HBOT initiation, ideal pressure and duration protocols, identification of patient subgroups most likely to benefit, and cost-effectiveness compared to standard care. Until these data emerge, clinicians must weigh the mechanistic rationale and limited evidence against the costs, uncertainties, and regulatory status of off-label HBOT application.
For now, patients with Bell’s palsy and their physicians face a familiar dilemma in emerging medical science: promising signals without definitive proof, innovation outpacing evidence, and the perpetual challenge of translating physiological possibility into clinical reality.
Sources
- HBOT for post-partum Bell's palsy with anti-phospholipid syndrome: case report (Frontiers in Rehabilitation Sciences, 2026)
- HBOT as effective adjuvant therapy in Bell's palsy: case series (J Family Med Prim Care, 2025)
- FDA Consumer Update: Hyperbaric Oxygen Therapy
- Hyperbaric oxygen as therapy for Bell's palsy (Undersea Hyperb Med, 1997)