6 doctors weighed in:
What causes fever blisters/ cold sores on my upper lip?!?
6 doctors weighed in

Dr. Ralph Morgan Lewis
Family Medicine
2 doctors agree
In brief: Cold sores
Cold sores/fever blisters are cause by the herpes simplex virus.
There are 2 types—oral & genital. Either type can cause a "cold sore" although the oral type is usually involved with lip lesions. There are several otc treatments to lessen symptoms, but prescription anti-viral meds work better to clear the lesions. Herpes, however, is not cured; it is suppressed & can reappear.—>.

In brief: Cold sores
Cold sores/fever blisters are cause by the herpes simplex virus.
There are 2 types—oral & genital. Either type can cause a "cold sore" although the oral type is usually involved with lip lesions. There are several otc treatments to lessen symptoms, but prescription anti-viral meds work better to clear the lesions. Herpes, however, is not cured; it is suppressed & can reappear.—>.
Dr. Ralph Morgan Lewis
Dr. Ralph Morgan Lewis
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1 comment
Dr. Ralph Morgan Lewis
—> during periods of physical or emotional stress. The virus can be transferred even if blisters are not apparent. If you take supplements, be careful with arginine, as it can trigger an outbreak. Lysine, on the other hand, may help suppress the virus.
Dr. Jana Tomsky
Family Medicine
2 doctors agree
In brief: Herpes simplex virus
It is very common virus everybody is expossed once upon the time in life.
Outbreak may happen for variety of reasons ( fever, exhaustion, period in woman, etc... Most efective treatemnt is oral anitviral medication ( it is a prescription)

In brief: Herpes simplex virus
It is very common virus everybody is expossed once upon the time in life.
Outbreak may happen for variety of reasons ( fever, exhaustion, period in woman, etc... Most efective treatemnt is oral anitviral medication ( it is a prescription)
Dr. Jana Tomsky
Dr. Jana Tomsky
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1 doctor agrees
In brief: Herpes Virus
In many cases these are caused by the herpes virus.

In brief: Herpes Virus
In many cases these are caused by the herpes virus.
Dr. Dante De Crescenzo
Dr. Dante De Crescenzo
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