A fever blister, cold sore or oral herpes is a lesion caused by herpes simplex virus type 1. It can be a single blister or a cluster of them, usually appearing on the lips, sometimes inside the mouth or the nose, as well.
About fever blisters
One of the main characteristics of fever blisters is their recurrence. The first outbreak, upon the infection with the virus, usually occurs in the childhood. The virus probably enters the body through a small cut or crack in the skin. After the initial outbreak passes, which takes from 5 to 10 days, the virus remains in the body. There is no permanent cure for the virus so fever blisters may keep coming back periodically, depending on a person’s overall health and the immune system.
Certain triggers can cause the virus to re-activate and cause the blisters again. Those triggers may involve stress, infections, illnesses, malnutrition, dehydration and similar. For some people, fever blisters keep coming back every few months and some people only have them a couple of times in their life. There are even those who carry the virus but never actually have fever blisters.
Stages of fever blisters
The first stage of fever blisters or oral herpes is called prodrome stage. This is basically the warning stage and the only stage when remedies and medications can actually help. This stage is characterized by tingling or itching where the blister will later appear. The area may also turn slightly red.
In the stage two the actual sore or blister will appear. There can be only one blister but it is usually a cluster of several smaller ones. They are filled with clear fluid, with redness around them.
The stage three is also called the weeping stage, because this is when the blisters will burst and the fluid will ooze out. The fluid is mainly clear but some blood and pus can also be expected.
During the fourth stage, the fever blister will start to heal under a scab or crust that forms over it. The scab is usually yellowish or red. Sometimes at this stage new blister forms as the previous one heals.
The fifth and final stage is when the scab falls off. Sometimes a second scab will form before the blister heals completely.
It takes from five to 14 days for fever blisters to heal. It may take less time if the blisters are not touched, peeled, pierced and such.