Cold sores Chancres Canker sores
These sores may seem similar but they’re often confused. However, their differences are important for treatment and prevention.
This article looks at the defining qualities of each type of sore.
EruptBreak openCrust overHeal
Most cold sores are caused by the herpes simplex virus 1 (HSV-1). They can also be caused by HSV-2. But that type’s more often seen in genital herpes.
Both HSVs are highly contagious. They’re most contagious through an active sore. But herpes can be transmitted even when 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 can also get oral herpes from infected objects like eating utensils and razors.
Once you’re infected with a herpes virus, it stays in your body forever. It may then cause outbreaks from time to time. Antiviral medications can suppress the virus and help prevent outbreaks.
The herpes virus doesn’t cause chancres or canker sores.
Mouth Lips Tongue Tonsils Anus Fingers Breasts Nipples
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.
Without testing for syphilis, someone can be infected for a long time before noticing symptoms. Chancres clear up with antibiotic treatment for syphilis.
Oral sex plays a large role in the syphilis epidemic. That’s due to chancres in the mouth.
Since chancre sounds much like canker, the terms are easy to confuse. But chancres are most often called chancres, while cankers are called canker sores. That can help you keep them straight.
Their exact cause is unclear. Triggers may include:
StressAllergiesDehydrationA weak immune systemMinor mouth injuriesFood sensitivitiesGeneticsHormonal shiftsVarious nutritional deficiencies (especially folic acid and vitamin B12)Some medications
Canker sores aren’t contagious. But they’re sometimes tied to contagious illnesses. For example, canker sores are more common in people with acute HIV infection. That’s due to their weakened immune system.
Most canker sores don’t need treatment. They generally heal on their own in three weeks or less. Serious sores or those that last extra long should be looked at, though.
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.
A Word From Verywell
If you have a strange sore on or around your mouth, talk to your healthcare provider or dentist. They’ll most likely be able to tell you what it is and how to treat it.
Be cautious with close contact, like kissing or sex, in case it’s something contagious.
Remember that some sore-causing infections can be transmitted even when you don’t have sores. Always practicing safer oral sex can protect you and your partner(s).
Aphthous ulcers (canker sores)Oral herpes (cold sores)Primary syphilis (chancres)Haemophilus ducreyi (chancroids)Lichen planusOral cancerOral candidiasis (thrush)Oral leukoplakia
Chancres are painless sores caused by a syphilis infection.
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