Cold sores, also known as fever blisters, are a common and often embarrassing condition that occurs when small groups of blisters form on the skin. In some cases, the blisters may rupture and leak a clear fluid.
The sores are most frequently located on the lips just under the nose. These outbreaks can also be found occasionally on the cheek, chin and nose.
Cold sores are highly contagious and spread easily through direct contact, such as kissing and sexual contact. They can also be spread by sharing personal items such as eating utensils, towels or razors.
The sores are caused by Herpes simplex virus-1 or 2 (HSV-1 HSV -2). Most individuals will become infected with the virus when they are children, and once the virus enters the bodies it never leaves. The virus quietly hides or sleeps in the central nervous system, but certain triggers cause it to “wake up” and travel along the sensory nerves and cause cold sores to appear on the skin.
Many people who suffer from cold sores know when one is coming by the distinctive (and often dreaded) tingling or burning, redness, itching or pain they feel around their lips or mouth. This is the first stage of a cold sore and these symptoms are sometimes called prodromal symptoms. This first stage can happen very quickly – from a few hours to a day. The next stage of a cold sore is the formation of one or more blisters. After the blister has developed, it breaks and an unsightly crust forms, which often becomes infected with bacteria such as staphylococcus. Within a few days this crust falls off and leaves behind an area of pinkish skin that heals without a scar. The entire process usually takes between 8 to 10 days.