An actual challenge, not a prank, to see how long one can withstand swishing a full shot (the cup attached on the bottle) of Listerine - *Cool Mint* inside their mouth.
This is usually very difficult to do for most people, given the fact that the formula for most Listerine products gives a burning sensation that damages the sensitive tissue inside your mouth.
But on the plus side, the victim of the Listerine Challenge gets a cleaner, fresher, mouth.
**this is in no way promoting the products of Listerine, or any dentists.
See also: cinnamon challenge
Friend 1: "Hey, you want to try the Listerine Challenge?"
Friend 2: "Okay, what do I do?"
Friend 1: "Swish this small cup full of Listerine - Cool Mint, in your mouth for 30 seconds, and you'll get 10$ dollars."
Friend 2: "Challenge accepted."
10 seconds later...
Friend 2: "Fuuuuuuuuuuu!!1!!"