Canker Sore vs. Cold Sores: Differences & Recovery Times

Canker Sore vs. Cold Sores: Differences & Recovery Times
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Canker Sore vs. Cold Sores: Differences & Recovery TimesClinical Content Reviewed by Dr. Jay Khorsandi, DDS
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Table of Contents

  1. Canker Sores
  2. Cold Sores
  3. Main Differences Between the Two
  4. Tips for Recovery
  5. References

Both canker sores and cold sores are common oral conditions affecting the mouth area.

The main difference between the two is the location of the sore. Canker sores form on the inside of the mouth, while cold sores are usually on the outside of the mouth, on the lips.

Cold sores are highly contagious. They are a type of infection, while canker sores are not.

Canker sores and cold sores generally heal on their own within a week or two. The discomfort associated with them can typically be treated with over-the-counter topical creams, numbing gels, and medications.

Canker Sores

Canker sores are some of the most common oral conditions. They impact about 20 percent of the population, and they are more common in women than men.

A canker sore can be caused by trauma to the mouth, such as biting the inside of your cheek. They can also be caused by stress, food sensitivities, or medications.

A canker sore is an ulcer that is also called aphthous stomatitis. They are small and usually round or oval. They can be painful and have a white, yellow, or gray center surrounded by a red ring.

A canker sore will usually heal on its own within two weeks and does not typically need medical attention. A canker sore can come back later and, in some cases, it can indicate an immune response in the body. If you have additional symptoms, be sure to contact your doctor.

Cold Sores

Cold sores are usually caused by the herpes simplex virus type 1 (HSV-1), which impacts nearly half of all people between the ages of 14 and 49 in the United States.3 They are not preventable and highly contagious.

They typically form as fluid-filled reddish blisters that break to create a crusty sore, generally on the lips. They can form on the tongue, gums, or roof of your mouth as well.

Cold sores are the result of a viral infection that stays in your body, and there is no specific cure for them. A cold sore outbreak can be triggered by additional illness, environmental aspects, or hormonal changes. Cold sores usually begin as a burning, itching, or tingling sensation, and they generally clear up on their own within 10 days.

More than half of the US population has dealt with canker sores and cold sores, and many don’t know the difference between the two or how to treat them.

Main Differences Between the Two

Canker sores and cold sores are not the same thing. Neither is typically a big cause for concern, and both will generally heal on their own without specialized treatment. However, there are some big differences between canker sores and cold sores.

Canker sore vs. cold sore:

  • Canker sores are usually caused by an external factor. They are an autoimmune response, while cold sores are viral infections.
  • Cold sores are highly contagious, while canker sores are not.
  • Canker sores are mostly on the inside of the mouth, while cold sores are on the outside.
  • Cold sores appear crusty, while canker sores are typically red rimmed with a whitish center.

The exact cause of a canker sore is not directly known, but there are known risk factors that can increase the odds of getting a canker sore. It is also possible that family history of ulcers can increase the risk for developing canker sores.

Cold sores are generally the result of exposure to the herpes virus that stays in your system forever. Herpes often does not cause any symptoms, but it can be transmitted easily through skin-to-skin contact with someone who has an active cold sore outbreak.

Cold sores are contagious from the first feeling of tingling or burning on the skin until they have completely healed. Avoid kissing or making contact with anyone else until the cold sore outbreak is over.

Tips for Recovery

Canker sores and cold sores both can be uncomfortable. There are some things you can do to speed up the recovery timeline and alleviate discomfort.

For canker sores:

  • Try numbing topical gel and over-the-counter pain medications to control pain.
  • Stay away from acidic and spicy foods.
  • Gargle with warm salt water or baking soda and water to speed up healing time and reduce pain.
  • Eat a vitamin-rich diet, and consider vitamin C and vitamin B complex supplements to hasten recovery.
  • Eat ice chips for the pain.

To manage cold sores:

  • Use over-the-counter antiviral topical ointments to speed up healing.
  • Try cortisone cream, applied directly to the area, to reduce swelling.
  • Ice the cold sore to help with pain and inflammation.
  • Consider antiviral medications to support the healing process.
  • Limit sun exposure, as this can trigger a cold sore outbreak and prolong the recovery of an active outbreak.
  • Wash your hands before and after contact with the cold sore and when applying medications.

If a cold sore or canker sore persists beyond two weeks, or you experience additional symptoms such as fever, fatigue, or nausea, call your doctor promptly.


What Is the Prevalence of Aphthous Stomatitis (Canker Sore)? (September 2020). MedScape. Date Fetched: July 1, 2021.

Canker Sores. (2021). American Academy of Oral Medicine. Date Fetched: July 1, 2021.

Cold Sores. (July 2020). NHS. Date Fetched: July 1, 2021.

Canker Sores and Cold Sores. (March 2005). The Journal of the American Dental Association. Date Fetched: July 1, 2021.

Canker Sores. (February 2019). U.S. National Library of Medicine. Date Fetched: July 1, 2021.

Interventions for Prevention of Herpes Simplex Labialis (Cold Sores on the Lips). (August 2015). Cochrane Library. Date Fetched: July 1, 2021.

Cold Sores vs. Canker Sores: What Are They and How Do I Get Rid of ‘Em? (July 2019). Penn Medicine. Date Fetched: July 1, 2021.

Cold Sores. (April 2016). U.S. National Library of Medicine (NLM). Date Fetched: July 1, 2021.

Disclaimer: This article is intended to promote understanding of and knowledge about general oral health topics. It is not intended to serve as dental or other professional health advice and is not intended to be used for diagnosis or treatment of any condition or symptom. You should consult a dentist or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment.