Positive effects of hydrogen-water bathing in patients of psoriasis and parapsoriasis en plaques
Zhu Q, Wu Y, Li Y, Chen Z, Wang L, Xiong H, Dai E, Wu J, Fan B, Ping L, Luo X. · Scientific Reports. 2018;8:8051.
What kind of evidence is this?
Human
Non-randomized parallel-controlled psoriasis study plus a six-person self-controlled parapsoriasis series
Skin, wound and aging research
Other forms
Not reported in this record.
Not reported in this record.
Methods at a glance
Adults with treatment-resistant plaque psoriasis or parapsoriasis en plaques recruited at two Fudan University hospitals.
Psoriasis: H₂-water bathing n=41 and contemporaneous control n=34; parapsoriasis: n=6 without a parallel control. One control participant withdrew and was counted as a non-responder.
Twice-weekly baths for eight weeks; parapsoriasis response was assessed over the same treatment period.
Whole-body immersion in freshly prepared H₂ water for 10–15 minutes twice weekly, three days apart, for eight weeks; existing psoriasis treatments generally continued.
H₂ dissolved in bath water — H₂ only at the point of exposure, not inhaled Brown's gas. Electrolysis generated H₂ and O₂ upstream, but pure H₂ was collected and dissolved into water.
Bath water H₂ 1.0 ppm, pH 6.8–7.3, 38–42 °C and oxidation-reduction potential −580 to −650 mV, checked before each treatment.
Not applicable — bathing, not gas inhalation; the generator and nanobubble H₂ flow were not reported.
No O₂ was reported as dissolved or co-delivered in the bathing intervention.
Psoriasis controls continued topical corticosteroid/calcipotriol and a Chinese patent medicine and bathed in tap water at least twice weekly; concomitant therapies differed and allocation was not randomized.
Outcomes and reported result
Psoriasis Area and Severity Index, pruritus visual-analogue score, lesion response in parapsoriasis and adverse events.
At week eight, PASI75 occurred in 10/41 versus 1/34 and PASI50 in 23/41 versus 6/34; pruritus change also favored H₂ bathing. All six parapsoriasis cases were reported as partial or complete responders. Two participants reported temperature discomfort; no other adverse reaction was reported.
The complete free PMC article, tables, figures and methods were checked for assignment, concomitant treatment, water chemistry, positive results, withdrawal, adverse events, device supply and conflicts.
A reported association, difference or mechanism is not automatically a clinical benefit. Null findings, outcome type, study design and precision all matter.
Cautions and applicability
Non-randomized, unblinded treatment selection; unequal and differing concomitant therapies; six-person uncontrolled parapsoriasis series; short follow-up; no sham H₂ bath. The bathing machine was supplied by Shanghai Yiquan Investment Limited Partnership; authors declared no competing interests and no explicit funding statement was identified, so funding absence is not inferred.
Exploratory evidence in selected treatment-resistant dermatology patients; it does not establish comparative efficacy or replace standard psoriasis/parapsoriasis care.
Not reported in this record.
Not reported in this record.
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.
Sources and record status
PMID: 29795283 · DOI: 10.1038/s41598-018-26388-3
Free full article in PubMed Central.
Complete PMC article and PubMed metadata; full-text extraction checked 9 August 2026.
2026-08-10