Cold sores,canker sores, andchancresare common sores that have both similarities and differences.
All appear in or around the mouth and chancres may also appear on the genitals.
However, these three types of sores have different causes and treatments.
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This article looks at the defining qualities of each jot down of sore and ways to manage outbreaks.
They’re mostly found around the lips.
They are also known as fever blisters.
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Causes
Most cold sores are brought on by the herpes simplex virus 1 (HSV-1).
Both HSVs are highly contagious.
They’re most contagious through an active sore.
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But herpes can be transmitted evenwhen you don’t have sores.
It’s possible to get an oral herpes infection through sexual activity.
But HSV-1 is more often picked up in childhood.
For example, a child can get it from a parent’s kiss.
you might also get oral herpes from infected objects like eating utensils and razors.
The herpes virus doesn’t cause chancres or canker sores.
It may then cause outbreaks from time to time.
During outbreaks, it’s possible for you to treat painful sores with gels containing lidocaine or benzocaine.
Over-the-counter creams containing docosanol may shorten the duration of an outbreak.
Prescription antiviral medications can suppress the virus and help prevent outbreaks.
The exactcauseof canker sores is unclear.
Triggers may include:
Canker sores aren’t contagious.
But they’re sometimes tied to contagious illnesses.
For example, canker sores are more common in people with acuteHIV infection.
That’s due to their weakened immune system.
Canker sores are usually round and white with a red border.
They can be painful for several days.
Most canker sores don’t need treatment.
They generally heal on their own in three weeks or less.
Oral steroid medications may also be prescribed for canker sores that don’t respond to other treatments.
A prescription mouth rinse with the steroid dexamethasone can help decrease pain and swelling.
In some cases, you may need a procedure called cautery, which destroys or burns the canker sore.
If underlying conditions are contributing to your canker sores, treating those conditions may also improve your canker sores.
Frequent canker sores can alert you to health problems.
For example, they may be the first obvious sign of a nutritional deficiency or immune-related problem.
Chancre Sores
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They can also appear on the:
Chancres are round, firm, and usually painless.
Because they don’t hurt, they often go unnoticed.
This is particularly true when they’re in the mouth.
Withouttesting for syphilis, someone can be infected for a long time before noticing symptoms.
Oral sex plays a large role in the syphilis epidemic.
That’s due to chancres in the mouth.
Sincechancresounds much likecanker, the terms are easy to confuse.
But chancres are most often calledchancres, while cankers are calledcanker sores.
That can help you keep them straight.
Untreated syphilis can cause serious health problems as it progresses.
Is a chancroid the same as a chancre?
Achancroidis not the same as a chancre.
A chancroid is a very painful, soft skin ulcer on the genitals and/or throat.
It’s sexually transmitted by the bacteriaHaemophilus ducreyi.
Chancroids are rare in the United States.
Chancresare painless sores triggered by a syphilis infection.
Cold sores and canker sores also look different.
Canker sores are typically round and white or yellow in color with a red border.
Cold sores appear in clusters, while canker sores are typically a single lesion.
Chancres differ from cold sores and canker sores because they are typically painless.
Though they can resemble a canker sore, they don’t always appear in the mouth like canker sores.
Summary
Three similar-sounding mouth sores have key differences.
Cold sores are around the mouth and because of a virus.
Chancres are in or on the mouth and related to syphilis.
Canker sores are always inside the mouth and have many possible causes.
It’s important to distinguish between the sores for proper treatment and prevention.
National Center for Biotechnology Information, U.S. National Library of Medicine: InformedHealth.org.Cold cores: Overview.
Johns Hopkins Medicine.Oral herpes.
Cedars Sinai.Everything you ever wanted to know about canker sores.
2024;12(4):e8723.
Centers for Disease Control and Prevention.Sexually transmitted disease surveillance 2016.
National Institute of Dental and Craniofacial Research.Fever blisters & canker sores.
