Some mouthwash can be strong–very strong as a matter of fact. Sometimes, if you leave it in your mouth too long, the tingle may turn to a burning sensation.
A few kinds of mouthwashes are so strong in fact, they make us wonder how strong.
One researcher, when shopping, thought about how strong his mouthwash was at killing germs and decided to try it against the current COVID-19 coronavirus.
The findings are actually promising.
A new study conducted by researchers at the Penn State College of Medicine has found that a common dental item can inactivate human coronaviruses: mouthwash and oral rinses.
For the study, the results of which were published in the Journal of Medical Virology, researchers tested various oral and nasopharyngeal rinses — which included a 1% solution of baby shampoo (which is used in dental office rinses), a neti pot, peroxide sore-mouth cleansers, and mouthwashes — to determine how well they inactivated human coronaviruses, namely 229e, a strain that can cause the common cold.
The mouthwash and oral rinses tested — which included Listerine Antiseptic, Orajel Antiseptic Rinse, and Crest Pro‐Health, among others — were also efficacious, they found: “Many inactivated greater than 99.9% of the virus after only 30 seconds of contact time and some inactivated 99.99% of the virus after 30 seconds.”
Researchers put the virus in a solution with each of the products for 30 seconds, then one minute and finally for two minutes (Critics point out the timing is likely longer than the average person would keep mouthwash in their mouth).
To detect how much of the virus was inactivated, researchers diluted the solutions and put them in contact with human cells.
After a few days, they counted how many human cells remained alive after exposure to the products.
Among the findings, the 1% baby shampoo solution inactivated the virus by 99.9% after two minutes, while several types of mouthwash were able to inactivate the virus by 99.9% after only 30 seconds of contact time.
“Even if the use of these solutions could reduce transmission by 50%, it would have a major impact,” Craig Meyers, professor of microbiology and immunology and obstetrics and gynecology, who led the study, along with his team of researchers, said in a release on Monday.
“The data suggests that if you have a virus in your mouth, it would kill it” and could reduce your ability to spread it to others, Myers says, even though researchers believe its too early to know exactly how these findings would affect people who already have the virus and their ability to overcome it.
Though Meyers personally uses mouthwash twice a day he cautions people not to use these products in the hopes of fighting Covid-19.
“I would say wear your mask, do your social distancing.
Do what you’re supposed to be doing but this could just be an extra help,” Meyers says.
Stuart Gansky, one of the principal investigators on an ongoing UCSF clinical trial, said he and his team are planning to assess whether using an oral rinse before a dental procedure works to reduce virus transmission.
The other part of the small pilot trial aims to see whether regular mouthwash use will improve symptoms for people who have the virus, Gansky said.
The trial, which is not yet accepting participants, will test four types of mouthwash, including CloSys, Oral-B Mouth Sore, Crest Pro-Health Multi-Protection and Listerine.
Another study published in July by the Journal of Infectious Diseases did link certain oral rinses to inactivating SARS-CoV-2.
Researchers in Germany tested eight commercial types of mouthwash in a cell culture test and found Sars-CoV-2 viral load was reduced dramatically after 30 seconds.
However, the authors concluded that further studies are still needed and that mouthwashes are not suitable for treating Covid-19.