According to the Mayo Clinic, cold sores, also called fever blisters, are common and are due to a strain of the herpes virus. This strain is called herpes simplex virus type one. Genital herpes are caused by the type two virus, but according to the Mayo Clinic, either strain can cause sores in the facial area or the genitals. Treatment is not necessary, as the cause is a virus, but it may reduce the symptoms associated with the cold sore. Over-the-counter cold sore medications may be used to treat the symptoms or your doctor can prescribe a medication if you have cold sores frequently. Fever blisters are often recurrent and can be transmitted to others. Cold sores last between 7 and 10 days and go through several stages before disappearing.
Prodrome Stage
According to the National Library of Medicine (NLM), the first stage of the cold sore is called the tingling stage, or prodrome stage. For some individuals, the symptoms that occur prior to the development of a fever blister may be recognizable. For others, the symptoms may go completely unnoticed. Examples of such symptoms include: tingling, numbness, pain, soreness and swelling at the site where a cold sore will form. According to the NLM, this stage lasts about one to two days.
Blister Stage
At this stage the blister forms. According to the Mayo Clinic, the fever blister is a small, painful, fluid-filled bump. These blisters are typically raised, red, and occur near the mouth. In most cases, more than one blister will form at a time. The blister will last for about two days. In addition to physical discomfort, the blisters can be unsightly.
Weeping Stage
According to the NLM, the weeping stage, also called the ulcer stage, lasts only one day. At this point the blister breaks open and appears as a red, open sore. The center may become gray and ooze liquid. According to the NLM, this is when the herpes virus is most likely to be transmitted to others.
Scabbing Stage
The fever blister is now healing as it enters the scabbing stage. For about two or three days the open sores will form scabs that may break open and bleed. There can still be pain or burning at the site of the sores. The scabs will fall off and reform at least once or twice before the cold sore disappears entirely. According to the NLM, cold sores do not usually leave a scar.
