What is the difference between a cold sore and a canker sore? Is it true that if you have a canker sore, you have herpes?

- asks Katie from Colorado

January 29, 2007
A cold sore, at left, and a canker sore, right. [CREDIT: COLGATE.COM]
A cold sore, at left, and a canker sore, right. [CREDIT: COLGATE.COM]

Canker sores and cold sores are common disorders of the mouth, irritating millions of Americans. Although many people use the terms canker sore and cold sore synonymously, they are different conditions.

A canker sore is a painful ulcer, or open sore, that can develop on the tongue and the inside linings of the cheeks, lips, and throat; you can have more than one at a time, and they can recur throughout your life. The cause of canker sores is unclear, but possible culprits may include viral infection, which could result from something like an injury to the mouth due to dental work, aggressive tooth cleaning, or biting the tongue or cheek. When an open sore becomes infected after its onset, it’s considered a canker sore.

Canker sores are not considered to be contagious, and are not caused by the herpes virus. They occur in women more often than men and can occur at any age, but usually first appear between the ages of 10 and 40. In most cases, canker sores will heal by themselves, but may need to be treated with an antibiotic or an anti-viral medicine, depending on the type of infection that sets in.

Cold sores, however, are contagious and usually occur outside the mouth, appearing as small red blisters on the lips, chin, cheeks, or in the nostrils. Also known as fever blisters, 95-percent of recurrent cold sore outbreaks are caused by Type 1 herpes simplex virus, not the Type 2 strain that can cause genital herpes.

Unfortunately, once a person has an episode of cold sores, the herpes simplex virus remains in the body for life. The virus lies dormant in the nerve cells of the skin and may emerge again as an active infection at or near the original site. The cold sores will replicate only during an outbreak, usually stemming from fever, stress, or exposure to the sun. After the outbreak has passed, the virus retreats back into the nerve cells, waiting to strike again; the virus’ ability to lie dormant makes it difficult to treat effectively. Though cold sores cannot be cured, anti-viral medications can be helpful to reduce their frequency and to limit the duration of an occurrence.

When an open cold sore lesion is present, there is a large chance of spreading the infection to others, so the blistery-lipped should avoid direct contact with others, and yes, that means kissing. Also be warned: touching an active sore allows transmittance of the virus through your fingertips. Follow these tips and you’ll be thanked for sparing your friends the herpes simplex virus, the gift that keeps on giving.

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alex says:

Try Canker Cover – amazing for canker sores! Mine was gone in a day. It’s a pill like disc that covers the sore and protects it from food and drink and then it heals the sore.

Amanda says:

Trie liquid skin. It’s like an unnoticeable bandaid if you just wanna wait it out.

Molluscum is a tricky infection. Thanks for posting this.

Ashley says:

Thank you! My friend kept teasing me saying I had herpes, but now I am sure it it just a harmless canker!

cass says:

One of the healthiest tools for canker sores is pure salt. Place it directly on the sore holding lip or tongue out for timr. It numbs area. Do it numerous times in a day and the sore can be gone in a day or three depending on size. No chemicals entering body.

Teresa says:

If you have a persistent and painful canker sore, your dentist may be able to help. Brief application of a special acid can essentially cauterize the sore and speed healing. A brief sting is better than weeks of pain!

Sam says:

I have a canker sore on my lip and it’s not painful at all, should i leave it alone or will it get worse?

ALD says:

“95-percent of recurrent cold sore outbreaks are caused by Type 1 herpes simplex virus, not the Type 2 strain that can cause genital herpes.”

Just FYI – both type 1 and type 2 strains of herpes can cause genital herpes when exposed to the genitals.

Mason says:

Finally, I straight forward question with a straight forward answer with the best picture for it on the internet. You have no idea how much I appreciate this.

nohi says:

If I have a canker sore on my lip what can i do to heal it?

John says:

I got you all beat! 4% RX only lidocaine. Medical careers are awesome!

jasmine says:

think i have a canker sore fastest way to get ride of it pleaseee

Cmoore says:

I started looking at pics of canker sores on Google, & it brought up people suffering with HIV. Considering I have a canker sore on the inside of my lip, & an infected tooth that needs to be pulled, this report made me feel more at ease.

Star says:

I have three canker sores. One on my gums and two small ones on the inside of my right cheek right by the one on my gums. The only problem that I think I have is that my mouth is a bit swollen. Is that normal? I’ve had them for the past four days and I’m in A LOT of pain. It is only on one side, so I’m afraid of the swelling to get worse and have my face seem swollen; and only on one side.
I have an appointment with my dentist, but I have to wait a week. Can anyone help with quick and efficient remedies?

I think that is among the so much significant information for me. And i am happy reading your article. However want to observation on few general issues, The web site taste is perfect, the articles is truly nice : D. Good task, cheers

starr says:

I have 5 canker sores on my lip one on my tongue out of no where, I’ve been very sick for the past few days but I feel fine today. I just noticed them today due to the pain. Plus I have have a tooth infection. Is it normal to have so many in a short period of time?!

Lana says:

I’ve noticed I get canker sores in my mouth when I’m drinking a lot of orange juice or even mountain dew (which has orange juice in it)… they seem to come from citrus/highly acidic foods/drinks… otherwise my mom has even noticed them visiting when she uses certain kinds of toothpaste! Salt burns like crazy, but supposedly it helps? I’d just avoid the citrus/tomato/acidic foods & drinks… & get some orajel or something to deaden it… I have one right now and it is KILLER :P

Anonymous says:

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Jax L says:

I had the two mixed up. Now I know its Canker sores I get all the time. Just wish I knew why. ouchy! Thanks

Kimmie Gill says:

I create a poultice out of red wine and small piece of cotton (cut from a dishtowel or surgical gauze, etc) put it on at night. Mine go away using the red wine in 24 hours. I have tried other things such as preparations for canker sores, antibacterial mouthrinse, etc. but it stings too much for too little effect. I have also “held” red wine in my mouth for extended time in the area…awkward because have to hold my head in position to keep the liquid on it. But if I’m at home for the day, it works. I get many of these because of a medicinal side-effect of a drug I must take for a chronic neurological condtion. The key is to start treating them right away…the moment I feel one coming. These little things certainly make life difficult if they persist! Blessings to all.

Rubi says:

i was extremely sad not knowing the cause of this terrible Canker sore and was not even sure it WAS a canker sore. so glad i found this website, i was beginning to think maybe it was something else. My sore came out of absolutely NOWHERE. i mean i haven’t been sick, haven’t had a fever and i’m very careful with my lips and what i use on them. Friends teasing me, saying it was mouth herpes was very depressing. I’ve had this for about a week, and will try a Canker Cover because i feel like its healing but not as fast.

Steve says:

The fastest way I have found to shorten the life of cold sores herpes1 is to take control by squeezing the hell out of it and immediately follow with alcohol pad pressure. Gives a new meaning to the word pain but shortens lifespan many days. Be sure to cover before squeezing with tissue to avoid

Steve says:

Spraying and spreading and be sure to pop all pustules.

Sheri Farrell says:

Lysine…it’s natural and comes in a tablet or liquid. I prefer liquid so you can take some drops, then dab some on your lip to relieve the pain. Stops the breakout if you start using them right at onset. JUST DO IT like my mama said.

Mhazi says:

Much thanks to your contributions …the world will benefit

Concerned Citizen says:

Thank you for shedding light on this serious issue!!!

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