A cold sore, or fever blister, is a single or group of blisters that appears on the lip. After the blisters break, a scab forms that can last several days.

Cold sores usually heal in 2 to 3 weeks without leaving a scar.

Cold sores can be mistaken as canker sores. Canker sores are a result of a bacterial infection and appears on the mucous membrane inside the mouth.

Cold sores spread from person to person by close contact, such as kissing. They are usually caused by herpes simplex virus type 1 (HSV-1), and less commonly herpes simplex virus type 2 (HSV-2). Both of these viruses can affect the mouth or genitals and can be spread by oral sex. The virus can spread even if you don’t see any sores.

Testing and Treatment

There is no cure for cold sores, but treatment can help manage outbreaks. Prescription antiviral medicine or creams can help sores heal more quickly. They may also make future outbreaks happen less often, shorter in duration, and less serious.

The office visit is $35 and blood tests are $25 each for HSV I or HSV II. If possible at the time of visit, a culture can be done for $50 and blood testing would be required.

For more information about cold sores: