Hydrogen peroxide can be used to disinfect items around the house, or as an antiseptic to keep minor skin cuts from getting infected. So why not rinse your mouth with the colorless, caustic liquid to kill the coronavirus?
This idea isn't like President Donald Trump's potentially deadly suggestion that led to memes of him swigging Clorox bleach. Mouthwashes with low concentrations of hydrogen peroxide are on the market and may help treat gum disease caused by bacteria.
This month, British researchers published a review in the journal Function of mouthwash chemicals, including hydrogen peroxide, that they say "should be considered as a potential way to reduce transmission" of the coronavirus.
Just one problem.
"The virus doesn't just sit inside the mouth, so (that) if we swish it will be dead," said Mark S. Wolff, dean of the University of Pennsylvania School of Dental Medicine. "A chemical in the mouth is not getting into the nasal cavity or the lungs. And if I'm coughing, I'm reinfecting my mucosa" -- the membranes that line the respiratory system.
And there are other problems with the idea. Like toxicity. And no solid science.
"Some of these agents, such as ethanol and hydrogen peroxide, may, if used several times a day over a period of two to three months, induce inflammation" in the mouth and throat, warned the British team, led by Valerie B. O'Donnell, director of the division of infection and immunity at Cardiff University School of Medicine.
Thomas E. Rams, director of the oral microbiology testing lab at Temple University's Kornberg School of Dentistry, said, "It's all supposition at this point. There are no studies or solid data."
Studies are not in the works, Rams added, because dental practices were shut down except for emergencies. (On May 8, Pennsylvania revised state guidance to allow all dental procedures provided they can be performed safely.)
This is "an under-researched area," the British scientists acknowledged.