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Symptoms and Signs of Canker Sores

Doctor's Notes on Canker Sores

Canker sores, also known as aphthous ulcers, are common causes of painful sores in the mouth. Signs and symptoms of canker sores are as follows: small (less than 1 cm) oval round ulcers with a reddish border. They can occur in the gums, under the tongue and inside the cheeks and lips.

The exact cause of canker sores is not known. The following is a list of factors that have been implicated in triggering canker sore outbreaks in individuals: anxiety, stress, genetics, environmental factors, medications and/or food allergies. In addition, diseases such as Crohn’s disease and ulcerative colitis been associated with canker sores.

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Medically Reviewed on 3/11/2019

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Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.