Anyone that gets those small ulcers in the lining of the mouth knows how painful they can be. Though not contagious, they can appear quickly and recur.
However, there are some helpful ways to deal with that problem. You may want to try pricking a vitamin E capsule and apply the contents to the sore.
Another thing that may help is adding one teaspoon of baking soda to one half of a cup of water to swish your mouth with to cleanse and reduce pain.
Mouthwash or substituting one teaspoon of salt to a full glass of water and gargling is another option.
Apple Cider vinegar or some Milk of Magnesia applied to the Canker sore with a cotton swab is said to kill bacteria as well.
Take at least 500 mg. of vitamin C with bioflavonoids two or three times a day to help battle the problem is also advisable.