Whiskey, or any hard spirit. Both in the way you would imagine and also if you just hold the spirit in your mouth around the offending peg. Also, and hand on heart I've had relief from this. Place ice or something else very cold in the web between your thumb and the other fingers on the hand on the opposite side from the pain. Many moons ago there was a very aggressive bouncer in a wee music club I used to frequent, he didn't like anyone but he particularly didn't like me. To the extent that when he was on shift one evening with a toothache, the other door staff warned me to give him a wide berth. Ever the risk taker, I instead offered him the ice cube advice. I made a friend that evening and we still talk, decades after said club closed.