By Dr. Brian McDonough

PHILADELPHIA (CBS) – Cold sores are caused by a type of virus called herpes which is contagious. They usually show up on the lips or the mouth as a cluster of blisters with a red base.

Another name for these cold sores is fever blisters. Cold sores can feel itchy, dry and painful. Many people say they get a tingling feeling before they appear on the skin.

It is best to treat cold sores as soon as they appear. When we see someone in the office we give them antiviral medications. Pills are most effective but creams can be used as well.

A cold sore can last two to three weeks when a herpes infection appears. It will heal completely but more sores will return later on. When people have recurrence they usually heal faster — in about seven to ten days. Certain things increase the chance of a recurrence including fever, flu, hot or cold weather extremes and a weakened immune system. The use of sunscreen on the lips and face can help.

Reported By Dr. Brian McDonough, KYW Newsradio Medical Editor

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