ATTENTION

If you or someone you know is experiencing a mental health crisis, call 988 for 24/7 free and confidential crisis support. You do not have to be suicidal to call. Access more info and resources on suicide prevention, emotional and mental health support

toggle mobile menu Menu
toggle search menu

Site Navigation

Supplemental

Menu

Canker sore

Canker sore

Lip pulled back to show canker sore on inside of lower 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 of: August 6, 2023

Author: Healthwise Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Healthwise is a URAC accredited health web site content provider. Privacy Policy. How this information was developed to help you make better health decisions.

© 1995- Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.