There is no scientific evidence to suggest that Listerine can cure toenail fungus. However, anecdotal evidence suggests that a Listerine soak may help get rid of the fungus in a few days. To make a bath with this mild antifungal agent, mix it with lukewarm water in a 1:2 ratio or with vinegar in a 1:1 ratio. Soak your feet in this bath for 40-60 minutes every day till the fungus clears up.