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Clinical Reference Systems: Pediatric Advisor 10.0
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Cold Sores (Fever Blisters)

DESCRIPTION

  • a cluster of painful 1- to 3-mm bumps or blisters on the outer lip
  • on one side of the mouth only
  • tingling or burning on the outer lip at the same site where cold sores previously occurred.

CAUSE

Cold sores are caused by the herpes simplex virus (usually Type 1). The first bout follows contact with someone with herpes. Thereafter, the cold sores recur in 2% of people when the virus (which lives in the sensory nerve) is reactivated by sunburn, fever, friction, or physical exhaustion.

EXPECTED COURSE

The blisters will rupture, scab over, and dry up. The whole process takes 10 to 14 days. The sores do not cause scars. Treatment can shorten the course by many days.

HOME TREATMENT

  1. Antiviral ointment

    Once you get fever blisters, you usually can't shorten the time that you have them unless you start applying an antiherpes ointment as soon as any small bumps appear. These ointments require a prescription. If you don't have an antiherpes ointment, cover the fever blisters with petroleum jelly to reduce the pain and to promote healing.

    Your child needs the ointment prescribed by your physician. The ointment can reduce the severity of the sores only if treatment is started early.

  2. Prevention

    Since fever blisters are often triggered by exposure to intense sunlight, prevent them in the future by using a lip balm containing sunscreen. If blisters are not yet present, apply an ice cube or ice pack to the tingly area continuously for 90 minutes. This will sometimes abort the infection.

    Avoid spreading this germ to another person's eye because an infection there can be serious. Therefore, discourage picking, and wash the hands frequently. Since the condition is contagious, have your child avoid kissing other people during this time. If your child is young and puts everything in his mouth, avoid sharing toys with other kids for a week.

    If your teenager is going skiing or to the beach and has had frequent herpes flareups in the past, despite careful use of sunscreen, call your physician. Recent research has found that starting oral antiherpes medication (pills) before such outings can prevent most flareups.

CALL YOUR CHILD'S PHYSICIAN DURING OFFICE HOURS IF:

  • Any sores occur near the eye.
  • The sores last longer than 2 weeks.
  • You have questions about antiherpes ointments.
  • You have other concerns or questions.

Written by B.D. Schmitt, M.D., author of "Your Child's Health," Bantam Books.
Copyright 1999 Clinical Reference Systems