How has molecular hydrogen been studied in brain injury?
24 papers. Randomized human trials: 4. Human single group and observational studies: 7. Systematic reviews and meta analyses including human evidence: 1. Animal studies, including studies with cell experiments: 12.
Abstracts returned by the Europe PMC MED and PMC title and abstract query were reviewed. Human original studies and systematic reviews including human evidence have no lower year limit; animal and cell original studies start on January 1, 2024. Groups are ordered by first publication date, newest first.
Checked 2026-10-29 · 182 records searched
Randomized human trials4
A post hoc analysis of a randomized trial included 72 out of hospital cardiac arrest patients, with 39 receiving hydrogen mixed oxygen and 33 oxygen alone. Ninety day neurological and survival records were compared across institutional temperature management ranges.
Crit Care Med · 2024 · PMID 39133068
At 15 hospitals, 73 comatose patients aged 20 to 80 after cardiogenic out of hospital cardiac arrest were randomized double blind to 2% hydrogen mixed oxygen in 39 or oxygen in 34 for 18 hours. Neurological scores and survival were recorded at 90 days.
EClinicalMedicine · 2023 · PMID 36969346
Thirty seven people with severe subarachnoid hemorrhage were randomized to magnesium plus hydrogen, magnesium or control. The combined group received intravenous hydrogen rich solution for 14 days; ischemia, vasospasm, daily living scales and blood and cerebrospinal markers were assessed.
Stroke · 2021 · PMID 33349011
Fifty acute cerebral infarction patients within six to 24 hours of onset were randomized equally to 3% hydrogen inhalation or conventional intravenous medication. Inhalation lasted one hour twice daily for seven days; neurological and daily living scales, blood tests and brain MRI were assessed over two weeks.
J Stroke Cerebrovasc Dis · 2017 · PMID 28669654
Human single group and observational studies7
A man with ischemic stroke from internal carotid occlusion received daily molecular hydrogen and rhodiola capsules after bypass surgery. Immune cell and motor measurements were recorded over six months; this was a combined oral intervention, not hydrogen inhalation alone.
Open Med (Wars) · 2025 · PMID 41141928
Human data from a hydrogen inhalation study in subarachnoid hemorrhage examined nervous system lactate. Participant n and allocation are not stated in the abstract; accompanying 2023 cell and animal experiments are not separately included.
Biochem Biophys Res Commun · 2023 · PMID 37141668
An 11 year old boy in a persistent vegetative state after intracerebral hemorrhage received a 66.6% hydrogen and 33.3% oxygen mixture for four to six hours daily following prior rehabilitation and hyperbaric oxygen. Consciousness, motor scales and brain CT were recorded.
World J Clin Cases · 2022 · PMID 35211564
Five comatose post cardiac arrest patients received 2% hydrogen inhalation for 18 hours alongside temperature management. Blood hydrogen, blood and urinary oxidative markers and cytokines were measured before and at 3, 9, 18 and 24 hours.
J Clin Biochem Nutr · 2020 · PMID 33041520
One professional soccer player with mild traumatic brain injury received a hydrogen producing tablet through the buccal mucosa every two hours for 24 hours, starting approximately 15 minutes after injury. SCAT2 concussion assessments and adverse events were recorded.
F1000Res · 2019 · PMID 32595937
Five selected out of hospital cardiac arrest patients received hydrogen inhalation alongside temperature management in a pilot study. Adverse events, neurological status and survival at 90 days were recorded; concentration and duration are not stated in the abstract.
Circ J · 2016 · PMID 27334126
Arterial and venous hydrogen and physiological measurements were obtained in three acute cerebral ischemia patients before, during and after 3% or 4% hydrogen inhalation. A separate consistency assessment measured venous hydrogen after repeated 30 minute exposures in ten patients.
Med Gas Res · 2012 · PMID 22916706
Systematic reviews and meta analyses including human evidence1
A systematic review examined preclinical and human reports of inhaled gases in traumatic brain injury, distinguishing hydrogen, hyperbaric oxygen and other gases. Paper and total participant counts are not stated in the abstract.
J Neurotrauma · 2021 · PMID 33940933
Animal studies, including studies with cell experiments12
Mice with hypoxic ischemic brain injury received PBM, hydrogen inhalation or both. Behavior, physiology, neuronal and inflammatory markers were compared at 24 hours; animal n is not reported in the abstract.
Exp Brain Res · 2026 · PMID 42700227
Hydrogen was studied in mice with middle cerebral artery occlusion and reperfusion and SH SY5Y cells with oxygen glucose deprivation. Mice received inhalation; neurological scales, tissue, mitochondria and proteins were analyzed. Sample counts are not reported in the abstract.
J Stroke Cerebrovasc Dis · 2026 · PMID 42049119
Male C57BL/6 mice inhaled 1.3% hydrogen during 90 minutes of treadmill exercise before controlled cortical impact. Exercise, injury and control conditions were compared using oxidative markers, brain water and tissue assays; animal n is not stated in the abstract.
J Neurotrauma · 2026 · PMID 41877520
In mice with induced intracerebral hemorrhage, oral hydrogen releasing magnesium silicate nanosheets were compared with 3% hydrogen inhalation. Neurological behavior, brain water, tissue and inflammation were assessed; animal n is not reported in the abstract.
J Transl Med · 2026 · PMID 41654898
Neonatal piglets with hypoxic ischemic brain injury received hydrogen gas exposure. Cortical and white matter cells and ATF5 expression were analyzed; concentration, duration and animal n are not stated in the abstract.
Exp Neurol · 2026 · PMID 41386344
Sixty six male and female rats underwent 60 minute middle cerebral artery occlusion, followed by varying doses of 3.2 ppm hydrogen water alone or with minocycline after reperfusion and on days one and two. Day seven behavior and infarct volume were assessed; water administration route is not stated in the abstract.
Brain Res · 2025 · PMID 40935311
Twenty four rats were assigned in groups of six to control, head trauma, hydrogen rich saline or trauma plus hydrogen rich saline. Blood and brain IL 6, TNF α and tissue staining were assessed; saline administration route is not stated in the abstract.
Tissue Cell · 2025 · PMID 40774095
Male rats with induced subarachnoid hemorrhage received hydrogen inhalation, intrathecal magnesium, both or control conditions. Cortical potentials, cerebral blood flow, brain water and neurological scores were measured; animal n is not stated in the abstract.
Neurotherapeutics · 2025 · PMID 40442014
Mice with controlled cortical impact brain injury received hydrogen, needle embedding or both. Neurological scales, brain water, cells and inflammatory proteins were compared; hydrogen route and animal n are not stated in the abstract.
Cytokine · 2025 · PMID 40187069
Hydrogen rich water at varying concentrations was studied in seven day old rats with hypoxic ischemic brain injury and cultured pericytes under oxygen glucose deprivation. Oxidative markers, cerebral vessels and tissue were analyzed; animal administration route and sample counts are not reported in the abstract.
J Cell Mol Med · 2024 · PMID 39001579
Forty rats in five groups underwent brain irradiation with hydrogen rich water, memantine, both or control conditions. Hippocampal tissue, oxidative markers and inflammatory proteins were examined; the water administration route is not specified in the abstract.
Biomed Pharmacother · 2024 · PMID 38906028
Mice with repetitive mild traumatic brain injury were studied under hydrogen rich water and control conditions. Inflammatory and oxidative proteins, MR spectroscopy and imaging, myelin tissue and behavior were examined; administration route and animal n are not specified in the abstract.
Biomed Pharmacother · 2024 · PMID 38479178
Excluded 158 of 182 records: retracted paper or retraction or concern notice (2), narrative or mechanistic review or commentary (26), protocol without completed study data (5), direct population or molecular hydrogen intervention outside topic scope (16), correction notice (5), no abstract (4), animal or cell study before 2024 (99), preclinical review without confirmed human molecular hydrogen evidence (1).
View the search query
TITLE_ABS:("molecular hydrogen" OR "hydrogen gas" OR "hydrogen inhalation" OR "inhaled hydrogen" OR "hydrogen oxygen" OR oxyhydrogen OR "hydrogen rich") AND TITLE_ABS:("brain injury" OR stroke OR "cerebral ischemia" OR "cerebral ischaemia" OR "intracerebral hemorrhage" OR "intracerebral haemorrhage" OR "subarachnoid hemorrhage" OR "germinal matrix hemorrhage" OR "cardiac arrest") AND (SRC:MED OR SRC:PMC) AND FIRST_PDATE:[* TO 2026-10-29]
Search Europe PMCFrequently asked questions
How many papers directly studied people?
There are 11 human original studies. Counts refer to papers and may include follow up reports from the same participants or overlap with reviews.
Which populations and methods are distinguished?
Traumatic injury, ischemic stroke, intracerebral and subarachnoid hemorrhage, neonatal animal hypoxic ischemic injury and brain status after cardiac arrest are distinguished. Gas inhalation, intravenous hydrogen solution, hydrogen water and oral or buccal formulations are identified; routes absent from the abstract are marked unreported.
Which publication years are included?
Human studies have no lower publication year limit through the checked date. Animal and cell studies start in 2024, including 12 animal studies and 0 cell only studies.