Cold Sores
(Herpes Simplex Infections, Non-Genital)

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Medical Author:

Mohamad El Mortada, MD

Medical Author:

MaryAnn Tran, MD

Medical Author:

Corrine Young, PharmD

Medical Author:

Mary D. Nettleman, MD, MS, MACP

Mary D. Nettleman, MD, MS, MACP

Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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• Herpes simplex virus (HSV) can cause infections that affect the mouth, the face, the genitals, the skin, the buttocks, and the anal area.
• Of the two herpes simplex viruses (HSV-I and HSV-II) that are associated with skin lesions, cold sores are most commonly caused by HSV-I.
• HSV infection may not produce symptoms, but when it does, the hallmark symptom is a group of blisters on a red base. These blisters dry up rapidly and leave scabs that last anywhere from a few days to a few weeks.
• The virus resides deep in the nerve roots and may reactivate at a later time, causing the same symptoms in the same location.
• Cold sores can be treated with antiviral medications to reduce pain and shorten healing time.

Herpes simplex virus (HSV) can cause infections that affect the mouth, the face, the genitals, the skin, the buttocks, and the anal area. This article will concentrate on non-genital herpes. Many people acquire the virus and have no symptoms. For others, painful blisters appear near the area where the virus entered the body. Typically, the blisters heal completely but reappear at some point in the future when least expected (or desired). In between attacks, the virus resides deep in the roots of the nerves that supply the involved area. When herpes simplex lesions appear in their most common location, around the mouth and lips, people often refer to them as "cold sores" and "fever blisters."

There are two types of HSV, type I and type II. In general, type I, also known as herpes labialis, causes infections above the waist, most commonly as oral "cold sores." Type II infections occur mainly below the waist, leading to genital herpes. However, both types of HSVs are capable of infecting the skin at any location on the body.

Herpes infections, no matter where they occur first, have a tendency to recur in more or less the same place. Such recurrences may happen often (for example, several times per year) or only occasionally (for example, once or twice a year).