What Is Inside a Cold Sore?

The typical cold sore goes through 5 stages. During that time the cold sore, or blister located on the outside of the mouth, can have numerous appearances and be composed of different substances. It is important to know the warning signs of a cold sore so that you can prepare to ease the pain associated with it, and speed up the healing process. Cold sores, unlike canker sores that are located on the inside of the mouth, are contagious and should be handled with care.

Stage 1: The Tingling Stage

• The tingling stage is the first sign of an oncoming cold sore. During this stage you may feel the area that is effected feel itchy or swollen. Some even feel a "tingling" sensation. The cold sore virus has just started to attack the skin surface, however, no fluid is inside of the cold sore.

Stage 2: The Blister Stage

• Like any blister, the cold sore will begin to "bubble" up. There can be one blister over the area, or possibly multiple. During this time a fluid known as serum is placed between the top layers of your skin and the infected area. The serum actually acts as a buffer between your skin and the damaged cell below.

Stage 3: The Weeping Stage

• During this stage the blister (or blisters) will begin to break open, and the serum will leak out. Although during all stages you are able to pass the cold sore virus onto others, this stage is the most contagious. Underneath the blister, the damaged skin will begin to scab.

Stage 4: The Scabbing Stage

• As the cold sore begins to scab over, the infected area may begin to bleed. During this time the cold sore could contain both serum and blood (or more specifically platelets).

Stage 5: The Healing Stage

• Eventually the scab will break off and reform as a smaller scab. As this process moves on the scab will eventually not reform and the skin will be close to fully healing.