# Pharmacokinetics of hydrogen after ingesting a hydrogen-rich solution: A study in pigs.
> 水素リッチ溶液摂取後の水素薬物動態：ブタを用いた検討


## Abstract

Oral consumption of hydrogen-rich water is widely practiced, yet the associated pharmacokinetics had not been characterized. In this study, four 8-week-old female pigs received 500 ml of either hydrogen-rich or hydrogen-free glucose solution infused into the jejunum within 2 minutes via percutaneous gastrostomy. Hydrogen concentrations were monitored over 120 minutes in the portal vein, suprahepatic inferior vena cava, and carotid artery. Following hydrogen-rich solution administration, portal vein hydrogen peaked at 0.05 mg/L and remained above 0.016 mg/L (approximately 1% saturation) at 60 minutes. In contrast, carotid arterial hydrogen was undetectable, suggesting hepatic metabolism or pulmonary elimination before systemic circulation. The findings indicate that rapid ingestion of a highly concentrated hydrogen solution effectively elevates portal blood hydrogen levels and delivers hydrogen to the liver.

### Mechanism

Hydrogen absorbed from the jejunum elevates portal vein concentrations, but systemic arterial delivery appears limited due to hepatic metabolism or pulmonary elimination, preventing significant passage into the carotid circulation.

## Bibliographic

- **Authors**: Ichihara G, Katsumata Y, Moriyama H, Kitakata H, Hirai A, Momoi M, et al.
- **Journal**: Heliyon
- **Year**: 2021
- **PMID**: [34816046](https://pubmed.ncbi.nlm.nih.gov/34816046/)
- **DOI**: [10.1016/j.heliyon.2021.e08359](https://doi.org/10.1016/j.heliyon.2021.e08359)
- **PMC**: [PMC8591508](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8591508/)
- **Study type**: animal study
- **Delivery route**: hydrogen-rich water
- **Effect reported**: not assessed
- **H2 concentration**: 1%

## 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 34816046. https://h2-papers.org/en/papers/34816046
> **Source**: PubMed PMID [34816046](https://pubmed.ncbi.nlm.nih.gov/34816046/)