Herpes type 1 (HSV1) is the virus that is the most common cause of cold sores. HSV type 1 can also cause genital herpes, although this is more commonly caused by HSV type 2.
When HSV type 1 causes cold sores, painful grouped blisters and ulcers develop on the lips. They can last 1 to 2 weeks.
Oral antiviral agents like acyclovir or valacyclovir can be taken to reduce the severity of the outbreak and shorten the disease duration. This works best when treatment is started early when the blisters start to develop. In milder cases, topical acyvlovir creams can be used.
Once you have developed HSV infection, there is a tendency for it to recur as the virus resides in the nerves. However, in general the frequency and severity of the recurrence decreases with time.
