Recent public reports from the Chinese National Health Commission and the Chinese Center for Disease Control and Prevention recommend effective oxygen therapy measures as an element of general treatment for patients with COVID-19 (COVID-19). 1,2 Both documents disclose a rather peculiar proportion of hydrogen and oxygen (66.6% H2 to 33.3% O2) as the composition of the gas mixture for inhalation. Although high oxygen levels are given due to apparent lung dysfunction in COVID-19, mixing with hydrogen for a breathing mixture is still puzzling. Hydrogen is most likely to be added as an inert part of the breathing gas, but it may have beneficial effects in itself.

A recent study showed that hydrogen inhibits airway inflammation in patients with asthma, 3 This effect may improve the condition of inflammatory cytokines storms observed in COVID-19. Two multicenter randomized controlled trials (RCT) for COVID-19 inhalation of hydrogen were listed by the World Health Organization (WHO) for clinical trials registered in February and March 2020, but there is no evidence to support this approach. Another factor must be considered: high concentrations of hydrogen may cause static ignition and explosion.

Like other promising (and urgently needed) therapies in COVID-19, gas hydrogen therefore requires accelerated but careful research and approval approaches and has sufficient efficacy and safety guarantees. 5 Cutting off the simplest molecules in the universe may be a step back beyond the hydrogen research community of this particular coronavirus.