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Cold Sore or Canker Sore?

Have you ever had a sore develop on the outside of your lips or inside your mouth and not known if it was a cold sore or a canker sore? Let’s go through a description of each type of sore.

A cold sore is also called a fever blister and these are fluid-filled blisters that develop on the outside of the lips and mouth. Cold sores develop because of the herpes simplex 1 virus, which may be “asleep” in the body until a trigger such as stress, sunlight exposure or a fever occurs. You can get the virus from contact with someone who has a cold sore.

Symptoms, including pain, burning, and tingling, often start a few days before the blister appears. A blister may burst a few hours after it develops and begin to scab over, but it usually clears up after seven to twelve days. Cold sores are contagious throughout these seven to twelve days until they fully heal.

A canker sore is a small, pale white sore that develops on the inside of the mouth. This mostly means on the tongue, the inside of the cheeks, or the bottom of the mouth, but not usually on the roof of the mouth. Canker sores are painful and normally take a week or two to clear up.

Unlike cold sores, canker sores are not contagious so coming in contact with someone who has a canker sore does not put you at risk of developing them.

In summary, if you develop a sore on the outside of your mouth, it is usually a cold sore, especially if it develops after coming in contact with someone with a cold sore or if you’ve had a cold sore before. If one or more painful sores develop inside your mouth, they are usually canker sores.

Now you know the difference between a cold sore and a canker sore.