Skip navigation

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

URL of this page: //medlineplus.gov/ency/imagepages/9672.htm

Mouth sores

Mouth sores

Overview

Mouth ulcers are caused by many disorders. These include canker sores, leukoplakia, gingivostomatitis, oral cancer, oral lichen planus, oral thrush, and similar disorders.

Review Date 7/23/2024

Updated by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.