No, there’s no evidence gargling mouthwash can prevent or treat COVID-19

On Dec. 8, Sen. Ron Johnson (R-Wis.) claimed during a town hall meeting that gargling mouthwash “has been proven to kill the coronavirus.” Johnson later tweeted a link to a clinical trial that concluded commercially available mouthwash that contains beta-cyclodextrin and citrox (CDCM) can potentially reduce the viral load of SARS-CoV-2 — the virus that causes COVID-19 — in saliva.

This isn’t the first time this has been a topic of discussion. Last November, several news sites shared stories suggesting that mouthwash could “kill COVID-19 within 30 seconds,” citing this non-peer-reviewed study. Now that these claims are popping back up, the VERIFY team looked into whether mouthwash is an effective COVID-19 treatment. 

THE QUESTION

Can gargling mouthwash prevent or treat COVID-19?

THE SOURCES

• American Dental Association
• Colgate-Palmolive Company
• Johnson & Johnson: LISTERINE Professional
• Procter & Gamble: Crest and Scope
• Dr. Jason Kindrachuk, assistant professor of medical microbiology and infectious diseases at the University of Manitoba
  
  

THE ANSWER

No, there’s no evidence gargling mouthwash can prevent or treat COVID-19.

WHAT WE FOUND

Procter & Gamble-owned oral care brand Crest says “no mouthwash in the market has been approved by the FDA for the treatment or prevention of COVID-19.” The company adds on its website that its Crest and Scope mouthwashes “are not intended to prevent or treat COVID-19.” 

“While many of our mouthwashes have been proven to kill bad breath germs or 99% of germs that cause plaque and gingivitis. None of our mouthwash products have been tested against the coronavirus. Consumers should follow the preventative measures recommended by their health care provider,” Crest writes. 

Listerine, an oral care brand owned by Johnson & Johnson, also says its antiseptic mouthwash is “not intended to prevent or treat COVID-19 and should be used only as directed on the product label.” The company also says that rinsing with its mouthwash does not reduce the risk of COVID-19 infection, and encourages people to follow public health guidelines to mitigate the spread of the virus. 

“Consumers should follow the preventative measures issued by public health authorities including washing hands frequently, maintaining social distance, and avoid touching your eyes, nose, and mouth,” Listerine writes. 

The clinical trial cited by Johnson, which randomly tested 176 eligible patients, supported the relevance of using commercially available mouthwashes to reduce the viral load of SARS-CoV-2 in saliva. But the trial did not conclude that gargling mouthwash could prevent or treat COVID-19. 

Listerine says its researchers, who have reviewed recent studies and registered clinical trials regarding mouthwash and COVID-19, are working to explore the efficacy of Listerine mouthwashes in inactivating the virus. However, the company says “current available data is insufficient to support a conclusion that the use of Listerine mouthwash is helpful in the prevention and treatment of COVID-19.”

The American Dental Association told VERIFY in a statement: "There is currently no evidence to support that mouthwash reduces infection with or is a treatment of disease caused by the COVID-19 virus."

Colgate also says “no evidence currently exists that rinsing with a mouthwash or using a mouth spray protects against contracting or transmitting COVID-19.”

Throughout the pandemic, Johnson has been accused of spreading misinformation about the virus. In June, YouTube suspended his account for a week after the senator shared a video encouraging people to use alternative COVID-19 treatments.

More from VERIFY: No, you cannot inhale or ingest hydrogen peroxide to treat COVID-19