Fever blisters are a form of Herpes Labialis. They are also known as cold sores and are caused by the Herpes Simplex Virus Type 1. Fever blisters are small, red, yellow and crusty and appear around the mouth and lips. They should never be popped.
Canker sores and fever blisters are often confused. Canker sores occur only inside the mouth when fever blisters occur outside. Canker sores are not caused by Herpes Simplex 1.
If you discover that you have a fever blister, do not pop it. It is highly contagious and is easily spread through touch, especially kissing. Do not share utensils, glasses, food. Throw away your toothbrush, wash sheets and clothes and frequently wash your hands. Fever blisters can be spread to other parts of the body as well, so try to avoid contact until the blister is gone.
Fever blisters usually go away between one and three weeks, but they can come back again and again. Herpes Simplex 1 is an incurable virus and no vaccine exists. Wash blisters with soap and warm water and applying ice may alleviate the pain or discomfort.
If blisters last longer than three weeks, you may want to see a doctor. They may prescribe anti-viral medication to avoid frequent outbreaks, but as of now, there is no cure.
There are over-the-counter treatments such as ointments that numb the blisters and soften the crust around them. There are also antibiotics that a doctor can prescribe that control bacterial infections caused by the blisters.