Canker Sores (Aphthous Stomatitis) Symptoms & Causes

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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
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