Canker Sores

  • Description

    A canker sore is an ulcer on the mucous membrane inside your mouth. The medical terms for canker sores are aphthous stomatitis, ulcerative stomatitis, or aphthae.


    Recurrent canker sores are one of the most common inflammatory conditions of the mouth, afflicting about 20 percent of the general population. There may be a genetic predisposition for canker sores.

    It is not known what causes canker sores in all patients, although more than one cause is likely even for individual patients. Attempts to find bacteria or viruses linked with the disease have not proven fruitful, although an allergy to a type of bacteria commonly found in the mouth may cause some people to develop canker sores. The sores also might be an allergic reaction to certain foods eaten. stress may trigger canker sores as well.

    Injury to the mouth - such as scratching by abrasive foods or a stray toothbrush bristle - can trigger outbreaks of canker sores, although these factors probably do not cause the disorder. Hormonal disorders can contribute to canker sores, as can deficiencies of iron, folic acid, or vitamin b12. There may be an association of canker sores with helicobacter pylori, the same bacteria that cause peptic ulcers, and they have been associated with the aids virus.

    celiac sprue, a disease of the intestines caused by sensitivity to gluten (a group of proteins found in wheat, barley, and rye ), has also been associated with development of canker sores.


    Canker sores begin as small reddish oval or round swellings, usually on the movable parts of the mouth such as the tongue and the inside linings of the lips and cheeks. These swellings usually rupture within a day, are covered by a thin white or yellow membrane, and become edged by a red halo.

    The size of the sores varies from being an eighth of an inch wide in minor infections to an inch and a quarter wide in more severe cases. fever is rare and rarely there is an association of canker sores with other diseases.

    Usually a person will only experience a single or a few canker sores at a time. These sores generally heal within two weeks. Severe canker forms of the sore may leave scars. You should consult with your doctor if a canker sores continues or worsens for more than two or three weeks.


    Canker sores are very common and easy to recognize. Occasional canker sores merit self care only.

    Most doctors recommend that patients who have continual or frequently recurring bouts of canker sores undergo blood and allergy tests to determine if their sores are caused by a nutritional deficiency, an allergy, or some other correctable cause.

    Large or persistent ulcers may be due to drug allergies, acute herpes simplex, or certain digestive diseases.


    There are a number of treatments that reduce the pain and duration of canker sores for individuals whose outbreaks cannot be prevented. These treatments include numbing preparations, such as xylocaine, that are applied on the sores when a patient has only a few, and anti-inflammatory steroid mouthwashes or gels for patients with several sores. Cimetidine (Tagamet) – a medicine prescribed for heartburn and peptic ulcers - is sometimes useful for treating canker sores, although it is not specifically approved for canker sores.

    Some doctors recommend applying ice to the canker sore, avoiding food that is irritating, and rinsing your mouth with over-the-counter preparations such as diluted hydrogen peroxide or elixir of Benadryl. Some people find relief by rinsing the mouth with a solution of ½ teaspoon of salt in 8 ounces of water.


    Is this a cold sore or a herpetic ulcer?

    What medications can be taken to relieve the pain?

    How long before the pain subsides?

    What foods should be avoided?

    Should an allergy test be done?

    Could this be a dental problem?

    Vitamin and other nutrient supplements often prevent recurrence or reduce the severity of canker sores in patients with a nutritional deficiency. Avoidance of foods a patient is allergic to also can reduce the frequency of canker sore recurrence.

    Regular dental care, including brushing and flossing, as well as a balanced diet may help reduce the frequency and severity of canker sores.