# Molecular hydrogen as a treatment for ME/CFS: a mini-review of clinical evidence and mechanistic rationale.
> ME/CFSに対する分子状水素の可能性：臨床的エビデンスと作用機序に関するミニレビュー


## Abstract

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) remains without approved pharmacological options. This narrative mini-review examines the mechanistic basis for molecular hydrogen (H2), delivered mainly as hydrogen-rich water (HRW), as a candidate intervention. H2 exhibits selective antioxidant properties, suppresses inflammatory signaling, and supports mitochondrial homeostasis—biological targets relevant to ME/CFS pathophysiology, which involves oxidative stress, persistent inflammation, and disrupted energy metabolism. Three early-phase clinical studies of HRW in ME/CFS patients were evaluated; moderate-dose, extended-duration use showed preliminary reductions in fatigue and improvements in physical function with mild adverse effects. Parallels with Long COVID suggest broader applicability to post-viral fatigue states. Methodological constraints—small samples, self-reported outcomes, and absent objective biomarkers—limit current conclusions. Larger, rigorously controlled trials with remote biometric and biochemical monitoring are recommended to define responsive subgroups and clarify mechanisms.

### Mechanism

H2 selectively scavenges reactive oxygen species, suppresses NF-κB-mediated inflammatory signaling, and supports mitochondrial homeostasis, thereby addressing oxidative stress and impaired energy metabolism implicated in ME/CFS pathophysiology.

## Bibliographic

- **Authors**: Friedberg F, LeBaron TW
- **Journal**: Front Med (Lausanne)
- **Year**: 2026
- **PMID**: [41930109](https://pubmed.ncbi.nlm.nih.gov/41930109/)
- **DOI**: [10.3389/fmed.2026.1760210](https://doi.org/10.3389/fmed.2026.1760210)
- **PMC**: [PMC13039090](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13039090/)
- **Study type**: review
- **Delivery route**: hydrogen-rich water
- **Effect reported**: positive

## Delivery context

Hydrogen-rich water is a low-risk delivery route, but the achievable systemic hydrogen dose is bounded. For clinical applications, inhalation is the most efficient route; inhalation, however, carries explosion risk, and concentration matters (empirical LFL of 10% applies to inhalation environments; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

## Safety notes

Hydrogen-rich water is a low-risk delivery route, but the achievable systemic hydrogen dose is bounded. For clinical applications, inhalation is the most efficient route; inhalation, however, carries explosion risk, and concentration matters (empirical LFL of 10% applies to inhalation environments; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)
- [Inhalation safety threshold lineage](https://h2-papers.org/en/safety-notes/lineage)

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> **Cite as**: H2 Papers — PMID 41930109. https://h2-papers.org/en/papers/41930109
> **Source**: PubMed PMID [41930109](https://pubmed.ncbi.nlm.nih.gov/41930109/)