Canker Sores (Aphthous Stomatitis)

  • Overview

    Canker sores, or aphthous stomatitis, is an illness that causes small ulcers to appear in the mouth, usually inside the lips, on the cheeks or on the tongue.

    Canker sores are usually seen in children and adolescents from the ages of 10 to 19 years. For about one-third of the children affected, lesions continue to reappear for years after the initial outbreak.

    If your child has canker sores, it's important to know that they aren't contagious and can't be spread from one child to another.

    Boston Children's Hospital 
    300 Longwood Avenue
    Boston MA 02115

     fax: 617-730-0505

  • In-Depth

    What causes canker sores?

    The exact cause of this disease is not known, although there are many factors that are thought to be involved with the development of canker sores, including:

    • weakened immune system
    • certain allergies may cause the lesions to appear, such as: coffee, chocolate, nuts, cheese, citrus fruits, potatoes
    • stress
    • viruses and bacteria
    • trauma to the mouth
    • poor nutrition
    • certain medications

    What are the symptoms of canker sores?

    The following are the most common symptoms:

    • ulcers in the mouth, usually inside the lips, on the cheeks, or on the tongue
    • ulcers that are covered with a yellow layer and have a red base
    • no fever present (in most cases)
    • lesions usually heal between seven to 14 days
    • lesion tend to recur
  • Tests

    If you child sees a physician for her canker sores, doctors usually diagnose them based on a complete history and physical examination of your child. The lesions are unique and usually your child's physician can make a simple physical diagnosis. In addition, you child's physician may order the following tests to help confirm the diagnosis and rule out other causes for the ulcers:

    • blood tests
    • cultures of the lesions
    • biopsy of the lesion - taking a small piece of tissue from the lesion and examining it microscopically
  • It is especially important for your child to avoid spicy, salty or acidic foods, which may cause further mouth irritation.

    Since it's a viral infection, antibiotics are ineffective. Treatment may include:

    • increased fluid intake
    • acetaminophen for any fever or pain
    • proper oral hygiene
    • topical medications (to help decrease the pain of the ulcers)
    • mouth rinses (to help ease the pain)
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