4 doctors weighed in:
How do cold sores accur?
4 doctors weighed in

Dr. John Thaler
Dentistry - Prosthodontics
2 doctors agree
In brief: Virus
Two kinds of these are common, and both caused by virus.
Least worrisome, is the aphthous ulcer. Occurs on the soft tissues of the mouth -- inside lips, cheeks, under tongue. The worse one is herpes.The first time you get it, it can be anywhere in the mouth and outside the mouth. After that , in the mouth, it will only be on tight tissues -- roof of mouth, and right along gum line around teeth.

In brief: Virus
Two kinds of these are common, and both caused by virus.
Least worrisome, is the aphthous ulcer. Occurs on the soft tissues of the mouth -- inside lips, cheeks, under tongue. The worse one is herpes.The first time you get it, it can be anywhere in the mouth and outside the mouth. After that , in the mouth, it will only be on tight tissues -- roof of mouth, and right along gum line around teeth.
Dr. John Thaler
Dr. John Thaler
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Dr. Robert Kwok
Pediatrics
1 doctor agrees
In brief: Herpes virus returns
Cold sores on the lips or near the lips, are usually caused by recurrent oral herpes virus.
They start as a slightly raised reddish area, then form a cluster of tiny blisters, which break open soon, leaving a sore (ulcer) to heal up over a week. Sores appear more often when one is under stress or is ill from another illness. Younger babies with herpes should see a doctor when a sore appears.

In brief: Herpes virus returns
Cold sores on the lips or near the lips, are usually caused by recurrent oral herpes virus.
They start as a slightly raised reddish area, then form a cluster of tiny blisters, which break open soon, leaving a sore (ulcer) to heal up over a week. Sores appear more often when one is under stress or is ill from another illness. Younger babies with herpes should see a doctor when a sore appears.
Dr. Robert Kwok
Dr. Robert Kwok
Thank
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