Overview

Canker sores are painful white sores in the mouth. They usually begin with a tingling feeling, followed by a red spot or bump that turns white. Canker sores appear most often on the tongue, inside the cheeks, and inside the lips. They can be very painful and can make talking, eating, and drinking difficult.

A canker sore may form after an injury or stretching of tissues in the mouth, which can happen, for example, during a dental procedure or teeth cleaning. If you accidentally bite your tongue or the inside of your cheek, you may end up with a canker sore. Other possible causes are infection, certain foods, and stress. Canker sores are not contagious.

The pain from your canker sore should decrease in about a week, and it should heal in a few weeks. In most cases, a canker sore will go away by itself. Home treatment can ease pain and discomfort. If you have a large or deep canker sore that does not seem to be getting better after a few weeks, your doctor may prescribe medicine. Canker sores often come back again.

How can you care for yourself at home?

• Drink cold liquids, such as water or iced tea, or eat flavoured ice pops or frozen juices. Use a straw to keep the liquid from coming in contact with your canker sore.
• Eat soft, bland foods that are easy to chew and swallow, such as ice cream, custard, applesauce, cottage cheese, macaroni and cheese, soft-cooked eggs, yogurt, or cream soups.
• Cut foods into small pieces, or grind, mash, blend, or puree foods to make them easier to chew and swallow.
• While your canker sore heals, avoid coffee, chocolate, spicy and salty foods, citrus fruits, nuts, seeds, and tomatoes.
• To soothe your canker sore and help it heal:
  • Use an over-the-counter numbing medicine, such as Orabase.
  • Dab a bit of Milk of Magnesia on the canker sore 3 or 4 times a day.
• Put ice on your sore to reduce the pain.
• Take anti-inflammatory medicines to reduce pain, as needed. These include ibuprofen (Advil, Motrin) and naproxen (Aleve). Read and follow all instructions on the label.
• Use a soft-bristle toothbrush, and brush your teeth well but carefully.
• Do not smoke or use spit tobacco. Tobacco can cause mouth problems and slow healing. If you need help quitting, talk to your doctor about stop-smoking programs and medicines. These can increase your chances of quitting for good.