Canker sores

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Canker sores are shallow craters on the tongue or inside the cheek or lip. The sores usually have a reddened perimeter and yellow or white center. They can be painful and make it difficult to eat and talk.

An individual might develop one or several canker sores at a time. Canker sores do not spread to others. Any individual can develop one but teenagers, women and young adults are likely to develop them. Many individuals have canker sores at some point in their lives while others have them on a regular basis.

What are the possible causes?

The exact cause of canker sores is still unknown, but there is a tendency to run in families. In some cases, canker sores can develop if the following are present:

  • Individual is tired or stressed
  • Among women, having the menstrual cycle
  • Having braces on the teeth
    Canker sores
    The characteristic symptom of canker sores is developing a shallow ulcer on the tongue or interior of the cheek or lip.
  • Food allergies
  • Eating or drinking food or beverages that contain a lot of acid
  • Inadequate vitamins or minerals in the diet such as vitamin B12, iron and folic acid

What are the indications?

The characteristic symptom of canker sores is developing a shallow ulcer on the tongue or interior of the cheek or lip. The sore might be large or small with a reddened border and yellow or white middle.

The sores usually start with a burning or tingling sensation. It might be swollen or even painful. If a sore is present, it can make it difficult to eat or talk.

The sores can cause discomfort for 7-10 days. For minor sores, they fully heal in 1-3 weeks but large ones can take up to 6 weeks to heal. Some might develop a sore after the initial sore has healed. In most cases, canker sores can heal without scarring.


For most cases, canker sores do not require seeing a doctor since they settle on their own. Some of the measures that can be done at home to alleviate the discomfort include the following:

  • Eat soft, bland foods that are easy to swallow. The food should be sliced into smaller pieces or puree or mash it. Avoid chocolate, coffee, citrus fruits or juices, spicy or salty foods, seeds, nuts and tomatoes.
  • Avoid cold fluids such as iced tea or water. Oftentimes, fluid that touches the canker sores can trigger a stinging sensation. A straw must be used so that fluid will not touch the sore. In addition, you can hold an ice on the sore until it becomes numb.
  • Carefully brush the teeth to avoid touching the sore with the bristles.
  • Rinse the mouth using salt water. When preparing this rinse, dissolve a teaspoon of salt in a cup of warm water.
  • An over-the-counter medication such as milk of magnesia or Oragel can be placed on the sores. A cotton swab should be used to apply the medication at 3-4 times throughout the day. For children below 2 years of age, the doctor can prescribe suitable numbing medications.
  • A pain medication such as non-steroidal anti-inflammatory drugs (NSAIDs) including ibuprofen, aspirin or naproxen can be given.

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