Pronounced: ap-thus ul-sirsEn Español (Spanish Version)
Aphthous ulcers are also known as canker sores. They are painful, temporary sores that may occur anywhere in the mouth. The sores can occur one at a time or as a group. Although canker sores are not serious, other mouth sores may be. If you suspect you have this condition, make an appointment to see your doctor.
Canker Sores in the Mouth
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No one knows exactly what causes canker sores. They are thought to result from an overreaction of the immune system.
Canker sores are not a form of the herpes virus. Unlike herpes, canker sores cannot spread from one person to another.
Last reviewedNovember 2012by Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.