The Washington PostDemocracy Dies in Darkness

A GOP senator suggested gargling mouthwash to kill the coronavirus. Doctors and Listerine are skeptical.

Sen. Ron Johnson (R-Wis.) said, “Standard gargle, mouthwash, has been proven to kill the coronavirus,” which experts say is an oversimplification of the evidence found in studies. (Alex Brandon/Pool/AP)
Placeholder while article actions load

Sen. Ron Johnson (R-Wis.) recommended mouthwash as a treatment for the coronavirus during a town hall meeting Wednesday, immediately drawing criticism for suggesting gargling would offer protection.

The senator has been criticized for spreading conspiracy theories about the coronavirus and has promoted the use of drugs that have shown little to no evidence that they are effective in treating covid-19. YouTube this year suspended his account for violating the company’s medical misinformation policies. He has also expressed skepticism about the efficacy of coronavirus vaccine mandates and doses, which have undergone vigorous health testing.

His latest remarks run up against medical advice from a major producer of mouthwash and health experts.

“Standard gargle, mouthwash, has been proven to kill the coronavirus,” Johnson said, according to an audio recording of his remarks. “If you get it, you may reduce viral replication. Why not try all these things?”

Johnson later shared on Twitter a study on a public website that concluded mouthwash provides “modest benefits” in lowering viral loads in saliva. That study recruited 176 adults who had tested positive for the virus but were asymptomatic or showing mild symptoms.

Though mouthwash can partially kill off parts of the coronavirus in a person’s mouth, most infections occur through the nose, health experts said. “Even if gargling kills some of the virus, it won’t be able to clean the nasal area, nor the viruses that’s already penetrated deeper into the body,” said Kim Woo-Joo, an infectious-disease expert at Korea University.

“We’re looking at how [mouthwash] actually works on the virus itself rather than what it does to the body. I think those are two separate questions,” Nicholas Rowan, an ear, nose and throat surgeon and assistant professor at Johns Hopkins Medicine, told The Washington Post last year.

What those studies on mouthwash and coronaviruses actually mean

Raymond Niaura, interim chair of the epidemiology department at New York University, said that gargling wouldn’t hurt if accompanied by vaccination.

“That way, one would be at reduced risk for infection and have good smelling breath,” he wrote in an email.

Coronavirus variants like omicron, delta and mu are an expected part of the virus's life cycle, but vaccines can prevent more infectious variants from forming. (Video: John Farrell, Hadley Green/The Washington Post)

A dental-professional-focused website run by Listerine, one of the world’s most widely used mouthwash products, specifically says the evidence is not strong enough to conclude that it is helpful against covid-19.

Listerine “is not intended to prevent or treat COVID-19 and should be used only as directed on the product label,” the website notes in bold.

Through a spokeswoman, the senator said he wasn’t suggesting mouthwash would be a replacement for the vaccine. “During the town hall I was letting my constituents know we are seeing a surge of covid-19 cases in Wisconsin, to take it seriously, and do everything they can to stay healthy.”

Johnson, like many other conservatives, has backed the use of ivermectin as a treatment for covid-19. There is little evidence that the drug used on humans and livestock as an anti-parasitic works against the disease.

The Food and Drug Administration has warned people against using ivermectin to fight the coronavirus, saying such actions could prove lethal. “You are not a horse. You are not a cow. Seriously, y’all. Stop it,” the agency tweeted in August.

What is ivermectin, and how did people get the idea it can treat covid?

Johnson also supported the use of hydroxychloroquine, a drug that was hyped as a potential answer to the coronavirus by President Donald Trump last year.

Numerous studies and health experts have advised against using hydroxychloroquine, particularly when vaccines and, increasingly, other therapeutics are readily available in the United States. In June 2020, a study published in the New England Journal of Medicine found that hydroxychloroquine was no more effective than a placebo — in this case, a vitamin — in protecting people who had been exposed to the coronavirus.

Loading...