Hydrogen inhalation concentrations cluster into three operational bands: low (≤ 10%), mid (10–66%), and high (66–100%). Literature trends in safety and effect differ by band.
-
Gas Therapies for Neuro-Protection.
Crit Care Clin ・ 2026 ・ PMID 41260719
inhalation
not assessed
review
-
Hydrogen gas promotes neuroprotection and upregulates ATF5 expression in neonatal hypoxic-ischemic brain injury.
Exp Neurol ・ 2026 ・ PMID 41386344
inhalation
positive
animal study
-
Sixty-minute inhalation of molecular hydrogen decreases blood oxygen saturation but does not alter autonomic cardiac regulation at rest in healthy females: a randomized, double-blind, placebo-controlled crossover study.
Can J Physiol Pharmacol ・ 2026 ・ PMID 41401441
inhalation
mixed
human randomized controlled trial
-
Emerging Clinical Applications for Molecular Hydrogen.
Respir Care ・ 2026 ・ PMID 41449652
inhalation
not assessed
review
-
Hydrogen inhalation is associated with a transient rightward shift in prefrontal oxyhemoglobin asymmetry and autonomic modulation.
Sci Rep ・ 2026 ・ PMID 41582106
inhalation
positive
human observational study
-
Molecular hydrogen triggers TRPC4-TRPC4AP-dependent reversible calcium transients via extracellular influx.
Theranostics ・ 2026 ・ PMID 41799190
inhalation
positive
in vitro study
-
[The combined use of inhaled nitric oxide and molecular hydrogen in patients with post-COVID-19 syndrome].
Ter Arkh ・ 2026 ・ PMID 41859790
inhalation
positive
human randomized controlled trial
-
Neuroprotective Effects of Molecular Hydrogen via Oxidative Stress and Neuroinflammation Regulation in a 5xFAD Mouse Model.
Antioxidants (Basel) ・ 2026 ・ PMID 41897548
inhalation
positive
animal study
-
Molecular Hydrogen Modulates the Baroreflex Activity and Reduces the Vascular Adrenoreceptor Sensitivity to Phenylephrine and Lung Inflammation in Rats with Pulmonary Hypertension.
Biomedicines ・ 2026 ・ PMID 41898141
inhalation
positive
animal study
-
Hydrogen gas inhalation alleviated cerebral ischemia/reperfusion injury by regulating mitophagy in SH-SY5Y cells and mice via PTEN-induced kinase 1/Parkin pathway.
J Stroke Cerebrovasc Dis ・ 2026 ・ PMID 42049119
inhalation
positive
animal study
-
Respiratory-physiology modeling of therapeutic hydrogen inhalation: defining the fraction of inspired hydrogen (FiH) and flow-rate requirements.
Respir Res ・ 2026 ・ PMID 42050516
inhalation
not assessed
other
-
Effects of Inhalation of Hydrogen Gas on Allergic Conjunctivitis Model Mice.
J Ocul Pharmacol Ther ・ 2026 ・ PMID 42101321
inhalation
positive
animal study
-
Inhalation of hydrogen gas reduces exacerbations of acute aortic dissection in mice.
Life Sci ・ 2026 ・ PMID 42105975
inhalation
positive
animal study
-
Hydrogen restores central tryptophan and metabolite levels and maintains mitochondrial homeostasis to protect rats from chronic mild unpredictable stress damage.
Neurochem Int ・ 2025 ・ PMID 39653185
inhalation
positive
animal study
-
Evaluation of the therapeutic effects of nebulized inhalation of hydrogen-rich water on primary blast lung injury in C57BL/6 mice.
Surgery ・ 2025 ・ PMID 39799761
inhalation
positive
animal study
-
Molecular hydrogen inhalation modulates resting metabolism in healthy females: findings from a randomized, double-blind, placebo-controlled crossover study.
Med Gas Res ・ 2025 ・ PMID 39923133
inhalation
positive
human randomized controlled trial
-
Hydrogen-oxygen mixture inhalation as an adjunctive treatment to home-based exercise in older patients with knee osteoarthritis: an open-label, blinded-endpoint, randomized controlled trial.
Front Pharmacol ・ 2025 ・ PMID 39950118
inhalation
mixed
human randomized controlled trial
-
Performance of Unmodified Mechanical Ventilators With 2% Hydrogen Gas Mixtures.
Respir Care ・ 2025 ・ PMID 39969918
inhalation
not assessed
other
-
[Efficiency and safety of the integrated use of medical gases thermal heliox, nitric oxide and molecular hydrogen in patients with exacerbation of chronic obstructive pulmonary disease complicated by hypoxemic, hypercapnic respiratory failure and secondary pulmonary arterial hypertension in the post-COVID period].
Ter Arkh ・ 2025 ・ PMID 40327618
inhalation
positive
human randomized controlled trial
-
Molecular hydrogen mitigates traumatic brain injury-induced lung injury via NLRP3 inflammasome inhibition.
BMC Chem ・ 2025 ・ PMID 40405232
inhalation
positive
animal study
-
Molecular hydrogen attenuates cisplatin-induced nephrotoxicity by modulating β-hydroxybutyrate metabolism.
Mol Biol Rep ・ 2025 ・ PMID 40705191
inhalation
positive
animal study
-
Molecular hydrogen protects against sepsis-induced cardiomyopathy through improving Golgi stress-mediated autophagy, inflammation and apoptosis.
Br J Pharmacol ・ 2025 ・ PMID 40717465
inhalation
positive
animal study
-
Hydrogen Gas Attenuates Toxic Metabolites and Oxidative Stress-Mediated Signaling to Inhibit Neurodegeneration and Enhance Memory in Alzheimer's Disease Models.
Int J Mol Sci ・ 2025 ・ PMID 40725167
inhalation
positive
animal study
-
Clinical Efficacy of Hydrogen Therapy on Acute Radiation Enteritis and Inflammatory Response in Patients with Cervical Cancer Undergoing Concurrent Chemoradiation Therapy.
Adv Radiat Oncol ・ 2025 ・ PMID 41020280
inhalation
positive
human randomized controlled trial
-
Gut microbiota as a central mediator in hydrogen gas-induced alleviation of colitis via TLR4/NF-κB and Nrf2 pathway regulation.
Int Immunopharmacol ・ 2025 ・ PMID 41076929
inhalation
positive
animal study
-
Molecular hydrogen-mediated SIRT1 activation alleviates sepsis-associated encephalopathy by promoting mitophagy.
Eur J Med Res ・ 2025 ・ PMID 41351127
inhalation
positive
animal study
-
Molecular Hydrogen Affords Similar Neuroprotection to Therapeutic Hypothermia in a Porcine Model of Neonatal Hypoxic-Ischemic Encephalopathy.
Antioxidants (Basel) ・ 2025 ・ PMID 41462605
inhalation
positive
animal study
-
Application of Molecular Hydrogen in Early Heart Failure Development: Modulation of Microcirculation, Metabolism, Oxidative Stress, and Myocardial Status.
Antioxidants (Basel) ・ 2025 ・ PMID 41462618
inhalation
positive
animal study
-
Molecular hydrogen attenuates sepsis-induced cardiomyopathy in mice by promoting autophagy.
BMC Anesthesiol ・ 2024 ・ PMID 38395800
inhalation
positive
animal study
-
Hydrogen inhalation: in vivo rat genotoxicity tests.
Mutat Res Genet Toxicol Environ Mutagen ・ 2024 ・ PMID 38432775
inhalation
null
animal study
-
Molecular Hydrogen as a Promising Therapy Could Be Linked With Increased Resting Treg Cells or Decreased Fas+ T Cell Subsets in a IgG4-PF-ILD Patient: A Case Report.
In Vivo ・ 2024 ・ PMID 38688598
inhalation
positive
human case report
-
[Rehabilitation program of post-COVID-19 syndrome with the use of nitric oxide and molecular hydrogen].
Ter Arkh ・ 2024 ・ PMID 38713041
inhalation
positive
human randomized controlled trial
-
Inhalation of hydrogen gas mitigates sevoflurane-induced neuronal apoptosis in the neonatal cortex and is associated with changes in protein phosphorylation.
J Neurochem ・ 2024 ・ PMID 38849977
inhalation
positive
animal study
-
Molecular hydrogen promotes retinal vascular regeneration and attenuates neovascularization and neuroglial dysfunction in oxygen-induced retinopathy mice.
Biol Res ・ 2024 ・ PMID 38915069
inhalation
positive
animal study
-
The impact of hydrogen inhalation therapy on blood reactive oxygen species levels: A randomized controlled study.
Free Radic Biol Med ・ 2024 ・ PMID 38996821
inhalation
positive
human randomized controlled trial
-
Hinhalation therapy in patients with moderate COVID-19 (HCOVID): a prospective ascending-dose phase I clinical trial.
Antimicrob Agents Chemother ・ 2024 ・ PMID 39016593
inhalation
positive
human case report
-
Realizing brain therapy with "smart medicine": mechanism and case report of molecular hydrogen inhalation for Parkinson's disease.
Med Gas Res ・ 2024 ・ PMID 39073335
inhalation
positive
human case report
-
Combination of Hydrogen Inhalation and Hypothermic Temperature Control After Out-of-Hospital Cardiac Arrest: A Post hoc Analysis of the Efficacy of Inhaled Hydrogen on Neurologic Outcome Following Brain Ischemia During PostCardiac Arrest Care II Trial.
Crit Care Med ・ 2024 ・ PMID 39133068
inhalation
mixed
human randomized controlled trial
-
Inhalation of H/O(66.7 %/33.3 %) mitigates depression-like behaviors in diabetes mellitus complicated with depression mice via suppressing inflammation and preventing hippocampal damage.
Biomed Pharmacother ・ 2024 ・ PMID 39405908
inhalation
positive
animal study
-
The Role of Mast Cells in the Remodeling Effects of Molecular Hydrogen on the Lung Local Tissue Microenvironment under Simulated Pulmonary Hypertension.
Int J Mol Sci ・ 2024 ・ PMID 39456794
inhalation
positive
animal study
-
Hydrogen Gas Inhalation Alleviates Airway Inflammation and Oxidative Stress on Ovalbumin-Induced Asthmatic BALB/c Mouse Model.
Antioxidants (Basel) ・ 2024 ・ PMID 39594470
inhalation
positive
animal study
-
A case of lung injury due to a hydrogen explosion caused by the simultaneous use of two home folk remedies devices.
Acute Med Surg ・ 2024 ・ PMID 39634382
inhalation
adverse
human case report
-
Molecular Hydrogen Mediates Neurorestorative Effects After Stroke in Diabetic Rats: the TLR4/NF-κB Inflammatory Pathway.
J Neuroimmune Pharmacol ・ 2023 ・ PMID 35895245
inhalation
positive
animal study
-
Hydrogen Gas Inhalation Attenuates Acute Impulse Noise Trauma: A Preclinical In Vivo Study.
Ann Otol Rhinol Laryngol ・ 2023 ・ PMID 35962590
inhalation
positive
animal study
-
Molecular hydrogen exposure improves functional state of red blood cells in the early postoperative period: a randomized clinical study.
Med Gas Res ・ 2023 ・ PMID 36204784
inhalation
positive
human randomized controlled trial
-
Inhalation of 4% and 67% hydrogen ameliorates oxidative stress, inflammation, apoptosis, and necroptosis in a rat model of glycerol-induced acute kidney injury.
Med Gas Res ・ 2023 ・ PMID 36204787
inhalation
positive
animal study
-
Molecular hydrogen attenuates sepsis-induced cognitive dysfunction through regulation of tau phosphorylation.
Int Immunopharmacol ・ 2023 ・ PMID 36538853
inhalation
positive
animal study
-
Intermittent environmental exposure to hydrogen prevents skin photoaging through reduction of oxidative stress.
Geriatr Gerontol Int ・ 2023 ・ PMID 36807963
inhalation
positive
animal study
-
The Effect of Molecular Hydrogen on Functional States of Erythrocytes in Rats with Simulated Chronic Heart Failure.
Life (Basel) ・ 2023 ・ PMID 36836774
inhalation
positive
animal study
-
Efficacy of inhaled hydrogen on neurological outcome following brain ischaemia during post-cardiac arrest care (HYBRID II): a multi-centre, randomised, double-blind, placebo-controlled trial.
EClinicalMedicine ・ 2023 ・ PMID 36969346
inhalation
mixed
human randomized controlled trial
-
Molecular hydrogen promotes wound healing by inducing early epidermal stem cell proliferation and extracellular matrix deposition.
Inflamm Regen ・ 2023 ・ PMID 36973725
inhalation
positive
animal study
-
Effects of Hydrogen Gas Inhalation on Community-Dwelling Adults of Various Ages: A Single-Arm, Open-Label, Prospective Clinical Trial.
Antioxidants (Basel) ・ 2023 ・ PMID 37371971
inhalation
positive
human observational study
-
Hydrogen Attenuates Inflammation by Inducing Early M2 Macrophage Polarization in Skin Wound Healing.
Pharmaceuticals (Basel) ・ 2023 ・ PMID 37375833
inhalation
positive
animal study
-
Inhaled molecular hydrogen reduces hippocampal neuroinflammation, glial reactivity and ameliorates memory impairment during systemic inflammation.
Brain Behav Immun Health ・ 2023 ・ PMID 37449286
inhalation
positive
animal study
-
Molecular hydrogen: prospective treatment strategy of kidney damage after cardiac surgery.
Can J Physiol Pharmacol ・ 2023 ・ PMID 37463517
inhalation
positive
animal study
-
Attenuation of pulmonary damage in aged lipopolysaccharide-induced inflammation mice through continuous 2 % hydrogen gas inhalation: A potential therapeutic strategy for geriatric inflammation and survival.
Exp Gerontol ・ 2023 ・ PMID 37572992
inhalation
mixed
animal study
-
Antitumoral Activity of Molecular Hydrogen and Proton in the Treatment of Glioblastoma: An Atypical Pharmacology?
Brain Sci ・ 2023 ・ PMID 37626524
inhalation
not assessed
review
-
Molecular Hydrogen Reduces the Degree of Endothelial Alteration under Conditions of Chronic Heart Failure.
Bull Exp Biol Med ・ 2023 ・ PMID 37773571
inhalation
positive
animal study
-
The efficacy of hydrogen/oxygen therapy favored the recovery of omicron SARS-CoV-2 variant infection: results of a multicenter, randomized, controlled trial.
J Clin Biochem Nutr ・ 2023 ・ PMID 37970554
inhalation
positive
human randomized controlled trial
-
Hyperbaric hydrogen therapy improves secondary brain injury after head trauma.
Undersea Hyperb Med ・ 2023 ・ PMID 38055881
inhalation
positive
animal study
-
Hydrogen Inhalation Reduces Lung Inflammation and Blood Pressure in the Experimental Model of Pulmonary Hypertension in Rats.
Biomedicines ・ 2023 ・ PMID 38137362
inhalation
mixed
animal study
-
Molecular hydrogen alleviates lung injury after traumatic brain injury: Pyroptosis and apoptosis.
Eur J Pharmacol ・ 2022 ・ PMID 34883075
inhalation
positive
animal study
-
Molecular Hydrogen Positively Affects Physical and Respiratory Function in Acute Post-COVID-19 Patients: A New Perspective in Rehabilitation.
Int J Environ Res Public Health ・ 2022 ・ PMID 35206179
inhalation
positive
human randomized controlled trial
-
Development of a novel porcine ischemia/reperfusion model inducing different ischemia times in bilateral kidneys-effects of hydrogen gas inhalation.
Transl Androl Urol ・ 2022 ・ PMID 35558259
inhalation
mixed
animal study
-
Hydrogen Gas Inhalation Regressed Coronary Artery Aneurysm in Kawasaki Disease-Case Report and Article Review.
Front Cardiovasc Med ・ 2022 ・ PMID 35647081
inhalation
positive
human case report
-
Post-COVID-19 fatigue: A systematic review.
Front Psychiatry ・ 2022 ・ PMID 36032234
inhalation
positive
review
-
Dynamics of Metabolic and Oxidative Parameters of Erythrocytes during Treatment of Chronic Heart Failure with Molecular Hydrogen.
Bull Exp Biol Med ・ 2022 ・ PMID 36210415
inhalation
positive
human observational study
-
The effects of hydrogen treatment in a cigarette smoke solution-induced chronic obstructive pulmonary disease-like changes in an animal model.
J Thorac Dis ・ 2022 ・ PMID 36524091
inhalation
positive
animal study
-
Hydrogen gas and preservation of intestinal stem cells in mesenteric ischemia and reperfusion.
World J Gastrointest Surg ・ 2022 ・ PMID 36632117
inhalation
positive
animal study
-
Hydrogen and therapeutic gases for neonatal hypoxic-ischemic encephalopathy: potential neuroprotective adjuncts in translational research.
Pediatr Res ・ 2021 ・ PMID 32505123
inhalation
not assessed
review
-
Hydrogen Gas Alleviates Sepsis-Induced Brain Injury by Improving Mitochondrial Biogenesis Through the Activation of PGC-α in Mice.
Shock ・ 2021 ・ PMID 32590694
inhalation
positive
animal study
-
Molecular hydrogen downregulates acute exhaustive exercise-induced skeletal muscle damage.
Can J Physiol Pharmacol ・ 2021 ・ PMID 33356867
inhalation
positive
animal study
-
Hydrogen as a Potential Therapeutic in Obesity: Targeting the Brain.
Trends Endocrinol Metab ・ 2021 ・ PMID 33485760
inhalation
not assessed
review
-
Hydrogen Gas Therapy Attenuates Inflammatory Pathway Signaling in Septic Mice.
J Surg Res ・ 2021 ・ PMID 33639371
inhalation
positive
animal study
-
Chemical and Biochemical Aspects of Molecular Hydrogen in Treating Kawasaki Disease and COVID-19.
Chem Res Toxicol ・ 2021 ・ PMID 33719401
inhalation
not assessed
review
-
Inhaled gases as novel neuroprotective therapies in the postcardiac arrest period.
Curr Opin Crit Care ・ 2021 ・ PMID 33769417
inhalation
not assessed
review
-
Hydrogen gas alleviates sepsis-induced neuroinflammation and cognitive impairment through regulation of DNMT1 and DNMT3a-mediated BDNF promoter IV methylation in mice.
Int Immunopharmacol ・ 2021 ・ PMID 33773206
inhalation
positive
animal study
-
Molecular hydrogen alleviates asthma through inhibiting IL-33/ILC2 axis.
Inflamm Res ・ 2021 ・ PMID 33852061
inhalation
positive
animal study
-
Protective effects of hydrogen gas inhalation on radiation-induced bone marrow damage in cancer patients: a retrospective observational study.
Med Gas Res ・ 2021 ・ PMID 33942780
inhalation
positive
human observational study
-
Molecular Hydrogen Maintains the Storage Quality of Chinese Chive through Improving Antioxidant Capacity.
Plants (Basel) ・ 2021 ・ PMID 34072565
inhalation
positive
other
-
Inhalation of Molecular Hydrogen, a Rescue Treatment for Noise-Induced Hearing Loss.
Front Cell Neurosci ・ 2021 ・ PMID 34140880
inhalation
mixed
animal study
-
Randomized double-blind placebo-controlled trial of hydrogen inhalation for Parkinson's disease: a pilot study.
Neurol Sci ・ 2021 ・ PMID 34319514
inhalation
null
human randomized controlled trial
-
Application of Molecular Hydrogen in Heart Surgery under Cardiopulmonary Bypass.
Sovrem Tekhnologii Med ・ 2021 ・ PMID 34513069
inhalation
positive
human observational study
-
Inhalation of 2% Hydrogen Improves Survival Rate and Attenuates Shedding of Vascular Endothelial Glycocalyx in Rats with Heat Stroke.
Shock ・ 2021 ・ PMID 34524269
inhalation
positive
animal study
-
High concentration of hydrogen gas alleviates Lipopolysaccharide-induced lung injury via activating Nrf2 signaling pathway in mice.
Int Immunopharmacol ・ 2021 ・ PMID 34634688
inhalation
positive
animal study
-
Effect of hydrogen gas inhalation on patient QOL after hepatectomy: protocol for a randomized controlled trial.
Trials ・ 2021 ・ PMID 34674744
inhalation
not assessed
human randomized controlled trial
-
The effects of inhaling hydrogen gas on macrophage polarization, fibrosis, and lung function in mice with bleomycin-induced lung injury.
BMC Pulm Med ・ 2021 ・ PMID 34719405
inhalation
positive
animal study
-
Molecular Hydrogen: A Promising Adjunctive Strategy for the Treatment of the COVID-19.
Front Med (Lausanne) ・ 2021 ・ PMID 34746162
inhalation
not assessed
review
-
Therapeutic Effects of Hydrogen Gas Inhalation on Trimethyltin-Induced Neurotoxicity and Cognitive Impairment in the C57BL/6 Mice Model.
Int J Mol Sci ・ 2021 ・ PMID 34948107
inhalation
positive
animal study
-
Inhaled molecular hydrogen attenuates intense acute exercise-induced hippocampal inflammation in sedentary rats.
Neurosci Lett ・ 2020 ・ PMID 31715290
inhalation
positive
animal study
-
Molecular hydrogen attenuates sepsis-induced neuroinflammation through regulation of microglia polarization through an mTOR-autophagy-dependent pathway.
Int Immunopharmacol ・ 2020 ・ PMID 32058932
inhalation
positive
animal study
-
A "philosophical molecule," hydrogen may overcome senescence and intractable diseases.
Med Gas Res ・ 2020 ・ PMID 32189669
inhalation
not assessed
review
-
Constitutive hydrogen inhalation prevents vascular remodeling via reduction of oxidative stress.
PLoS One ・ 2020 ・ PMID 32302306
inhalation
positive
animal study
-
Chronic molecular hydrogen inhalation mitigates short and long-term memory loss in polymicrobial sepsis.
Brain Res ・ 2020 ・ PMID 32348775
inhalation
positive
animal study
-
Hydrogen gas alleviates blood-brain barrier impairment and cognitive dysfunction of septic mice in an Nrf2-dependent pathway.
Int Immunopharmacol ・ 2020 ・ PMID 32447221
inhalation
positive
animal study
-
Pharmacokinetics of a single inhalation of hydrogen gas in pigs.
PLoS One ・ 2020 ・ PMID 32559239
inhalation
not assessed
animal study
-
Hydrogen gas inhalation improves delayed brain injury by alleviating early brain injury after experimental subarachnoid hemorrhage.
Sci Rep ・ 2020 ・ PMID 32704088
inhalation
positive
animal study
-
Hydrogen Gas Inhalation Attenuates Endothelial Glycocalyx Damage and Stabilizes Hemodynamics in a Rat Hemorrhagic Shock Model.
Shock ・ 2020 ・ PMID 32804466
inhalation
positive
animal study
-
Hydrogen inhalation inhibits microglia activation and neuroinflammation in a rat model of traumatic brain injury.
Brain Res ・ 2020 ・ PMID 32814064
inhalation
positive
animal study
-
COVID-19 and molecular hydrogen inhalation.
Ther Adv Respir Dis ・ 2020 ・ PMID 32865158
inhalation
not assessed
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