Cold Sores and Fever Blisters: Get the Facts

Cold Sores are a common affliction for many people. Learn what causes cold sores, why they come back, and how you can treat them.

What are Cold Sores?

Cold sores, sometimes called fever blisters, are groups of small blisters that form on, or near the lips. They are caused by an infection from a virus called herpes simplex virus (HSV). The skin around these blisters is often red, swollen, and very painful.

The Virus that Causes Cold Sores

There are two types of this virus, HSV-1 and HSV-2. Both types can cause cold sores, though HSV-1 accounts for the majority of episodes. Most often the virus is caught in early childhood. Once the virus is in the body, there is no permanent cure.

How Cold Sores Flare Up

The virus situates itself in small bundles of nerve cells located just under the skin. Once the virus inhabits the nerve cells, it becomes inactive. For some people, the virus stays inactive forever, but there is no permanent cure. However, there are some triggers that can reactivate the virus and cause an outbreak of cold sores.

Most cold sores start to heal within a few days. Generally they are healed in 7 to 10 days.

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