I've never had one and I don't want one! I see what Kevin and Cat go through when they get one, it's terrible!
Anyway, Kevin uses this stuff to take away the pain so he can eat. It forms a crusty coating over the spot, and I *think* it might also disinfect?
Apparently, it hurts like a mofo to put it on though....
One more thing! I've also heard/read taking L-Lysine can help with canker sores. Don't know if it prevents them or heals after the fact, but you may want to check into it if you haven't already
(Kevin won't even take a daily multivitamin, so there ya go, LOL)