If you get multiple canker sores often, it is possible that they are not “canker sores” but rather a virus. My friend had a very bad outbreak of sores and the doctor said that the same virus that caused her chicken pox as a kid had resurfaced in her system and came out as mouth sores. A prescription medication got rid of the sores, but every once in a while they still come out. She told me that she can tell when a sore is about to come out and she gargles with listerine to catch it before it does. (She said only brand name listerine works for her).
