While it’s unlikely that dipping your genitals in mouthwash will cure that stubborn case of the clap, new research has revealed that a popular oral cleansing product can kill off the bacteria responsible for gonorrhoea in the mouth and throat.

Appearing in the journal Sexually Transmitted Infections, the study is the first to prove that Listerine actually has the power to defeat the rather unwelcome microbe Neisseria gonnorhoeae – finally validating a claim originally made by the product’s inventor in the nineteenth century, but which until now had never been scientifically investigated.

The researchers conducted two separate experiments, one of which took place in a petri dish while the other involved the use of live subjects. For the lab-based part of the study, the team added Listerine with a 21.6 percent alcohol content to cultures of Neisseria gonnorhoeae, and found that this significantly reduced the number of bacteria living in the dish after just one minute. In contrast, a saline solution had no effect on colony sizes.

They then recruited 58 men who tested positive for throat gonorrhoea, 33 of whom were asked to gargle with Listerine while the other 25 used a saline solution. After a minute of gargling, only 52 percent of bacteria remained in the throats of those who used the minty mouthwash, compared with 84 percent among the saline users.

Five minutes later, those who gargled with Listerine were five times less likely to test positive for throat gonorrhoea than those who used salty water.

While the study authors admit that the short follow-up time in this experiment means they can’t be sure that the effects of Listerine don’t wear off, the results are nonetheless encouraging. They also write that, given the continuing emergence of antibiotic-resistant strains of Neisseria gonnorhoeae, using mouthwash could prove an effective way to curb the spread of the illness, particularly when it comes to oral sex.