Herpes Simplex Virus/Cold Sores

What are cold sores?

Cold sores are small blisters around and/or inside the mouth, caused by the herpes simplex virus. They are often referred to as "fever blisters." Herpes simplex type 1 is the most common cause of cold sores.

Following initial infection, the herpes simplex virus becomes dormant for long periods of time but may reactivate, during which time cold sores reappear. Most episodes of cold sores do not last longer than two weeks. Extreme temperature changes, viral respiratory infections (the common cold), stress, or a weakened immune system are several of the triggers for recurrence of herpes simplex virus symptoms.

As herpes simplex viruses are contagious, they are readily spread to others by kissing, sharing cups or utensils, sharing wash cloths or towels, or by direct touching of the cold sore before it is healed. The virus may also be spread to others in the day or two before the cold sore appears.

What are the symptoms of cold sores?

Some children and adults never experience any symptoms with the first infection; others have severe flu-like symptoms (fever, body aches) and ulcers or blisters in and around the mouth. Recurrences of cold sores are usually not as severe as the original outbreak. Although each individual may experience different symptoms, the most common symptoms are:

  • A small blister or cluster of blisters on the lips, mouth, nose, gums or tongue that gradually enlarge, scab and crust over
  • Tingling, itching, and soreness of the lips and mouth lasting from three to seven days
  • Tingling or burning sensation of the lips may be a “warning sign” of a recurrent infection

The symptoms of cold sores may resemble other dermatologic conditions or medical problems. Always consult your children's primary care provider for a diagnosis.

What is the treatment for cold sores?

Specific treatment for cold sores will be determined by your child's primary care provider based on:

  • Your child's age, overall health, and medical history

  • Extent of the disease

  • Your child's tolerance for specific medications, procedures, or therapies

  • Expectations for the course of the disease

  • Your opinion or preference

Although the herpes simplex virus infection that causes cold sores cannot be cured, treatment may help alleviate and shorten the course of symptoms. Treatment may include oral antiviral medication, topical medication and/or pain relievers. Several of the available treatments are sold without prescription.

Always consult your child's primary care provider.

Reviewed by Debra D. Weissbach, MD, FAAP

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