Hydrogenology
Hydrogenology editorial study record

Successful treatment of myalgic encephalomyelitis/chronic fatigue syndrome using hydrogen gas: four case reports

Hirano SI, Ichikawa Y, Sato B, Takefuji Y, Satoh F. · Medical Gas Research. 2024;14(2):84–86.

HumanInhaled H₂Published 2024
Study record, not medical adviceThis page reports one source and Hydrogenology’s source-text extraction. It does not establish that molecular hydrogen is effective, safe or appropriate for any person. Human, animal and laboratory evidence must not be treated as equivalent.
Source and classification

What kind of evidence is this?

Evidence stream

Human

Reported design

Uncontrolled descriptive report of four cases

Research topic

Other neurological conditions

Administration classification

Inhaled H₂

Study result signal

Not reported in this record.

Outcome type

Not reported in this record.

Reported in the source

Methods at a glance

Population or model

Four people aged 18–58 years diagnosed with or considered probable ME/CFS after previous unsuccessful treatments.

Sample

4 cases: two men and two women.

Duration

Case 1: about 20 weeks; cases 2–4: 8–9 weeks.

Intervention

Inhalation of 6–7% H₂ from an MHG-2000α generator. Case 1 used 3–5 hours/day; cases 2–4 used 5–6 hours/day.

Hydrogen form

H₂ diluted in an unspecified balance gas — the article does not report Brown's gas or deliberate O₂ co-delivery.

H₂ specification

6–7% H₂ at a reported total device flow of 2 L/min; balance-gas composition was not stated.

H₂ flow

Approximately 120–140 mL/min H₂, calculated from 6–7% of the reported 2,000 mL/min total flow.

O₂ delivered with H₂

Not reported — the balance gas and absolute O₂ flow were not described.

Comparator

No control group; symptoms before treatment and during follow-up were compared within each case.

Reported, not endorsed

Outcomes and reported result

Outcomes measured

Self-reported fatigue, post-exertional symptoms, pain, sleep, cognition/brain fog, daily activity and other symptoms; one case used the Canadian Consensus Criteria score.

Reported result

All four cases reported improvement in selected symptoms. Case 1's self-scored total decreased from 29 to 13 over 20 weeks, with temporary worsening around COVID-19 vaccinations. Cases 2–4 were assessed by interview rather than a common validated scale. No causal effect can be separated from natural fluctuation, concurrent care, expectation or selective reporting.

Results-extraction completeness

The complete PMC case report was checked for each case, concentration, total and calculated H₂ flow, timing, outcomes, ethics and author employment; the absence of a reported balance gas is explicit.

A reported association, difference or mechanism is not automatically a clinical benefit. Null findings, outcome type, study design and precision all matter.

Interpretation limits

Cautions and applicability

Design and reporting cautions

Four selected uncontrolled cases based mainly on subjective reports, heterogeneous exposure and no blinded or standardized comparison. Four authors were employees of MiZ, the manufacturer of the inhaler used. The report cannot establish efficacy or replace evidence-based ME/CFS care.

Applies directly to

Only the four reported cases; hypothesis-generating evidence.

Preliminary appraisal framework

Not reported in this record.

Preliminary risk-of-bias status

Not reported in this record.

Appraisal rationale

Not reported in this record.

No single-study GRADE certainty rating is assigned. Certainty is assessed by important outcome across a complete eligible evidence set, not by attaching a final grade to one source.

Provenance

Sources and record status

Identifiers

PMID: 37929512 · DOI: 10.4103/2045-9912.385441

Publisher access

Free full article on PubMed Central.

Extraction basis

PMC full article and PubMed record; full-text and article-status check completed 8 August 2026.

Record revision

2026-08-10