Cold sores are small blisters that develop on the lips or around the mouth and are commonly caused by the HSV-1 infection, which is a type of herpes simplex virus (HSV).
Cold sores are highly contagious and very common; they can also be painful and take time to clear, so it is important to start treatment as soon as possible.
Cold sore outbreaks can be effectively treated with antiviral medication such as Aciclovir and Valaciclovir.