Canker sore

A canker sore is a painful white ulcer in the mouth. They appear most often on the tongue, inside of the cheeks, and inside of the lips. Unlike cold sores, canker sores are not contagious. But in some people they keep coming back. Canker sores cause pain that may make it difficult to eat or drink.

Canker sore

Canker sore on the inside of the lip

A canker sore is a painful white ulcer in the mouth. They appear most often on the tongue, inside of the cheeks, and inside of the lips. Unlike cold sores, canker sores are not contagious. But in some people they keep coming back. Canker sores cause pain that may make it difficult to eat or drink.

Current as ofOctober 3, 2018

Author: Healthwise Staff
Kathleen Romito, MD - Family Medicine
Martin J. Gabica, MD - Family Medicine
Adam Husney, MD - Family Medicine
Arden G. Christen, DDS, MSD, MA, FACD - Dentistry

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