Canker Sores (cont.)

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What are the causes of canker sores?

The cause of most canker sores is not well understood, and multiple factors may cause sores to appear. Some possible causes of canker sores include the following:

Are canker sores the same thing as fever blisters?

No, canker sores are not the same thing as fever blisters (cold sores).

Canker sores occur inside the mouth and are not contagious. Fever blisters are infections caused by the herpes simplex virus (HSV), they mostly occur on the lips and outside of the mouth, and they are very contagious.

Picture of cold sores and canker sores
Picture of cold sores and canker sores

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Medically Reviewed by a Doctor on 7/9/2014

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Canker Sores - Effective Treatments Question: Please describe what treatments have been effective for your canker sores.
Canker Sores - Symptoms Question: What were the symptoms of your canker sores?
Canker Sores - Topical Medications Question: What topical medications have been effective treatments for your canker sores?
Canker Sores - Oral Medications Question: Which medications have you tried for pain or to treat your canker sores? What would you recommend?
Canker Sores - Experience Question: Please describe your experience with canker sores.