A – Z of Illnesses & Conditions

Cold Sores:  Cold Sores, sometimes called fever blisters, are groups of small blisters on the lip and around the mouth. The skin around the blisters is often red, swollen and sore.

Cold sores are caused by a virus. The virus known as herpes simplex virus usually enters the body through a break in the skin around or inside the mouth. It is usually spread when a person touches a cold sore or touches infected fluid such as when sharing eating utensils or razors, kissing an infected person or touching that person's saliva.

A parent who has a cold sore often spreads the infection to his or her child in this way.  Cold sores can also be spread to other areas of the body. The first symptoms of cold sores may include pain around your mouth and on your lips, fever, a sore throat, or swollen glands. After the blisters appear, the cold sores usually break open and leak a clear fluid. Then a crust is formed. It takes several days to disappear  completely. For some people, cold sores can be very painful.

When small children drool it can sometimes be a sign that cold sores will soon appear. After the blisters appear, the cold sores usually break open and leak a clear fluid. Then a crust is formed. It takes several days to disappear completely.

You only need to visit your doctor if you think you or your child has become infected with the herpes simplex virus for the first time, or if the cold sores have not healed after 7 to 10 days.