Cold Sore vs. Canker Sore: What are they?

  • comments 0
  • views5,535

Difference between Cold Sore and Canker Sore

A cold sore is one of the two most common types of mouth problem, next to canker sores. Cold sores are also called fever blisters, and are often mistaken for canker sores. Cold sores are lesions, or eruptions on the skin around the mouth that look like small crusty blisters. The virus can actually stay in the nerve ganglion forever, popping up on occasion, and typically healing in a week or two.

Canker sores are also blister looking eruptions, called ulcers, which occur inside the mouth. While very common, canker sores are not contagious and are not caused by the herpes virus. Canker sores can pop up in groups, but can normally heal on their own accord within two weeks.

Causes of Cold Sores and Canker Sores

Cold sores are caused by herpes simplex 1. It is a virus, and it is contagious. Cold sores are transmitted initially through oral contact, but since they can live dormant inside the infected nerve for life, secondary outbreaks can be caused by stress or trauma to the area.

The cause of canker sores is unknown, but can be a sign of a more serious condition such as Crohn's disease. When a person experiences frequent or severe canker sore outbreaks, it is imperative to be checked out by a doctor to determine the underlying cause.

Treatment of Cold Sores and Canker Sores

Cold sores cannot be cured, but the symptoms can be alleviated somewhat by the use of oral health medications that include doconasol or benzyl alcohol. If a person thinks they feel a cold sore coming on due to symptoms of numbness or burning and itching, medications can suppress the symptoms and relieve pain.

Canker sores can be treated with over-the-counter products for pain relief. Benzocaine in gel form is the recommended treatment. Steroidal mouthwash can help with the inflammation and people with sensitivity to certain foods should avoid those foods.

Prevention of Cold Sores and Canker Sores

Since cold sores are caused by a virus, kissing or touching of the cold sore can spread the infection. It is possible that people with herpes simplex 2 (genital herpes) can spread the virus through oral-genital sex, but those blisters are normally not repeating. Avoid contact with any area that is blistered, as it is difficult to tell the difference between cold sores and non-contagious canker sores.

Since the cause of canker sores is unknown, it is hard to know how to prevent them, but it is suspected that a malfunction of the immune system is responsible. If a patient seems to get canker sores after eating certain foods it is recommended they avoid those foods altogether.


  • Cold sores and canker sores are commonly confused mouth ailments. While both are annoying and uncomfortable, cold sores are contagious and caused by a virus. Canker sores are not contagious, but there is yet a verifiable answer as to their cause.
  • Avoiding stress and eating a healthy diet are recommended to control the outbreak of both cold sores and canker sores, but there really is no proven way to keep them from happening.
  • See your doctor is you have frequent bouts of canker sores to see if there is a more important underlying condition, and also if either the canker sores or cold sores are not going away on their own.


comments Comments

Post a Comment
  • Name*
  • Email*