3 doctors weighed in:
What causes cold sores and fever blisters in the mouth and lips?
3 doctors weighed in

Dr. Kevin Considine
Family Medicine
1 doctor agrees
In brief: Virus
Cold sores are caused by the herpes virus and is a very common infection to get.
It is estimated that 90+% of population has been exposed to this virus in childhood. Usually it is triggered by stress, lack of sleep, excess sunlight etc.. Sometimes people get them recurrently or once in awhile or sometimes once then never again. It depends but can be treated by Acyclovir and related drugs too.

In brief: Virus
Cold sores are caused by the herpes virus and is a very common infection to get.
It is estimated that 90+% of population has been exposed to this virus in childhood. Usually it is triggered by stress, lack of sleep, excess sunlight etc.. Sometimes people get them recurrently or once in awhile or sometimes once then never again. It depends but can be treated by Acyclovir and related drugs too.
Dr. Kevin Considine
Dr. Kevin Considine
Thank
Dr. Kim Capehart
Dentistry
In brief: Virus
Cold sores are usually caused by hsv (type i or ii) but cold sores are usually cause by type i.
Cold sores are contagious and recurrence can be cause by uv light, stress, hormone fluctuation, to fever and sometimes, there is no apparent cause. Go to your doctor for appropriate treatment options such as anti-viral medications.

In brief: Virus
Cold sores are usually caused by hsv (type i or ii) but cold sores are usually cause by type i.
Cold sores are contagious and recurrence can be cause by uv light, stress, hormone fluctuation, to fever and sometimes, there is no apparent cause. Go to your doctor for appropriate treatment options such as anti-viral medications.
Dr. Kim Capehart
Dr. Kim Capehart
Thank
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