Since 1879, manufacturers claimed Listerine was effective at both cleaning floors and curing gonorrhea.
Now, more than a hundred years later, scientists have published the first ever randomized controlled trial testing the gonorrhea claim. The bad-breath mouthwash does indeed kill gonorrhea bacteria in both petri dishes and men's throats, Huffington Post reports.
The sexually transmitted infection can cause infertility, sterility and even death if left untreated. If continued trials show that Listerine's immediate effectiveness against gonorrhea translates into a long-term preventive tool, then people at high risk of the STI have a cheap and effective way to prevent the disease.
The mouthwash had a moderate effect on the amount of viable gonorrhea in the throat, but scientists aren't sure how long the results would last or how long men would have to gargle and rinse with mouthwash to prevent future infections in the throat.
The effect on the transmission of gonorrhea to other parts of the body is still unknown and Listerine's effect on women still needs to be tested.