Cold sore; Fever blister; Herpes simplex - oral; Oral herpes simplex
Herpes labialis is infection of the lips, mouth, or gums with the herpes simplex virus. It leads to the development of small, painful blisters commonly called cold sores or fever blisters.
Herpes labialis is a common disease caused by infection of the mouth area with herpes simplex virus type 1. Most people in the United States are infected with this virus by age 20.
The initial infection may cause no symptoms or mouth ulcers. The virus then remains dormant (asleep) in the nerve tissue of the face. In some people, the virus reactivates and produces recurrent cold sores that are usually in the same area, but are not serious.
Herpes virus type 2, which usually causes genital herpes and can infect babies during birth to infected mothers, can also cause herpes labialis.
Herpes viruses are contagious. Spread may occur through intimate and personal contact, or through contact with infected razors, towels, dishes, and other shared articles. Occasionally, oral-to-genital contact may spread oral herpes to the genitals (and vice versa).
The first episode may be mild or severe. It usually occurs in children between 1 and 5 years old.
Later episodes are usually milder.
An outbreak usually involves:
Diagnosis is made on the basis of the appearance or culture of the lesion. Examination may also show enlargement of lymph nodes in the neck or groin.
Viral culture, viral DNA test, or Tzanck test of the skin lesion may reveal the herpes simplex virus.
Untreated, the symptoms will generally go away in 1 to 2 weeks. Antiviral medications taken by mouth may help the symptoms go away sooner and decrease pain. Acyclovir, famciclovir, and valacyclovir are the three oral treatments currently available.
Herpes sores often come back again and again. The antiviral medicines work best if you take them when the virus is just starting to come back -- before you see any sores. If the virus returns frequently, your doctor may recommend that you take the medicines all the time.
Topical (rubbed onto the skin) antiviral cream (penciclovir andaacyclovir) may be used, but must be applied every 2 hours while you're awake. They are expensive and often only shorten the outbreak by a few hours to a day.
Wash blisters gently with soap and water to reduce the spread of the virus to other areas of skin. An antiseptic soap may be recommended. Applying ice or warmth to the area may reduce pain.
Tips to prevent future outbreaks include applying a sunblock or lip balm containing zinc oxide to the lips when you're outdoors. A moisturizing balm to prevent the lips from becoming too dry may also help.
Herpes labialis usually goes away by itself in 1 to 2 weeks. It may come back. Infection may be severe and dangerous if it occurs in or near the eye, or if it happens in immunosuppressed people.
Herpes infection of the eye is a leading cause of blindness in the United States, causing scarring of the cornea.
Call for an appointment with your health care provider if you have :
Avoid direct contact with herpes sores. Minimize the risk of indirect spread by thoroughly washing items such as towels in hot (preferably boiling) water before reuse. Do not share items with an infected person, especially when they have herpes lesions. Avoid triggers (especially sun exposure) if you are prone to oral herpes.
Avoid performing oral sex when you have active herpes lesions on or near your mouth and avoid receiving oral sex from someone who has oral or genital herpes lesions. Condoms can help reduce, but do not entirely eliminate, the risk of catching herpes from oral or genital sex with an infected person.
Both oral and genital herpes viruses can sometimes be transmitted even when the person does not have active lesions.
Haile-Mariam T, Polis MA. Viral illnesses. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, Pa: Mosby Elsevier; 2009:chap 128.
Habif TP. Warts, herpes simplex, and other viral infections. In: Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2009: chap 12.
© 2011 University of Maryland Medical Center (UMMC). All rights reserved.
UMMC is a member of the University of Maryland Medical System,
22 S. Greene Street, Baltimore, MD 21201. TDD: 1-800-735-2258 or 1.866.408.6885