Children & Adolescents Clinic

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Clinical Reference Systems: Pediatric Advisor 10.0
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Chickenpox (Varicella)


  • multiple small, red bumps that become thin-walled water blisters; then cloudy blisters or open sores; and finally dry, brown crusts (all within 24 hours)
  • repeated crops of these sores for 4 to 5 days
  • sores or crusts that are usually less than 1/4 inch across
  • rash that is on all body surfaces, but usually starts on head and back
  • some sores possibly in the mouth, eyelids, and genital area
  • fever (unless the rash is mild)
  • exposure to a child with chickenpox 14 to 16 days earlier.


Chickenpox is caused by exposure to a highly contagious virus.

A chickenpox vaccine is now available. Most physicians recommend this vaccine for all children who haven't had chickenpox. It can be given at any time after 12 months of age. Children up to 12 years old need just a single injection. Two injections 4 to 8 weeks apart are recommended for adolescents over 12 years and adults who have never had chickenpox.

Expected Course

New eruptions continue to crop up daily for 4 to 5 days.

The fever is usually the highest on the third or fourth day. Children start to feel better and stop having a fever once they stop getting new bumps. The average child gets a total of 500 chickenpox sores.

Chickenpox rarely leaves any permanent scars unless the sores become badly infected with impetigo or your child repeatedly picks off the scabs. However, normal chickenpox can leave temporary marks on the skin that take 6 to 12 months to fade. One attack usually gives lifelong immunity. Very rarely, a child may have a second mild attack.

Home Care

  1. Itching and cool baths

    The best treatment for skin discomfort and itching is a cool bath every 3 to 4 hours for the first few days. Add 2 ounces (4 tablespoons) of baking soda per tub of water. Baths don't spread the chickenpox. Calamine lotion can be placed on the most itchy spots after the bath. You can also massage the itchy spots with an ice cube for 10 minutes. If the itching becomes severe or interferes with sleep, give your child a nonprescription antihistamine called Benadryl.

  2. Fever

    Acetaminophen or ibuprofen may be given in the dose appropriate for your child's age for a few days if your child develops a fever over 102ƒF (39ƒC). Do not give aspirin to children and adolescents with chickenpox because of the link with Reye's syndrome.

  3. Sore mouth

    Because chickenpox sores also occur in the mouth and throat, your child may be picky about eating. Encourage your child to drink cold fluids. For infants, use a cup rather than a bottle because the nipple can cause pain. Offer a soft, bland diet and avoid salty foods and citrus fruits. If mouth sores become troublesome and your child is over age 4, have him gargle or swallow 1 teaspoon of an antacid solution four times a day after meals.

  4. Sore genital area

    Sores also normally occur in the genital area. If urination becomes very painful, apply some 2.5% Xylocaine (no prescription needed) to the genital ulcers every 4 hours to relieve pain.

  5. Acyclovir

    Acyclovir is an oral, anti-viral drug that can be used to treat chickenpox. It helps only if started within 24 hours of the appearance of the first sores. According to recent research, acyclovir has mild benefits: it reduces the number of sores by 20% and the days of illness by one. The complication rate is not reduced. If used, acyclovir needs to be taken for 5 days. The cost is $30 to $50. The drug has few reported side effects.

    Which children with chickenpox should receive acyclovir is a controversial topic. Physicians do agree that all children who have immune system defects, are taking steroids, or have a chronic skin or lung disease should receive acyclovir. Some physicians prescribe acyclovir for adults, college students, and high school students. Some also prescribe it for younger children who have social obligations (such as travel). Most physicians don't treat normal, healthy children with acyclovir.

  6. Prevention of impetigo (infected sores)

    To prevent the sores from becoming infected with bacteria, trim your child's fingernails short. Also, wash the hands with an antibacterial soap (such as Dial or Safeguard) frequently during the day. For young babies who are scratching badly, you may want to cover their hands with cotton socks.

  7. Contagiousness and isolation

    Children with chickenpox are contagious until all the sores have crusted over, usually about 6 to 7 days after the rash begins. To avoid exposing other children, try not to take your child to the physician's office. If you must, leave your child in the car with a sitter while you check in. Once all the sores have crusted over (after 6 to 7 days), your child does not have to stay home anymore even though he still has scabs. It may take 2 weeks for all of the scabs fall off.

    Most adults who think they didn't have chickenpox as a child had a mild case. Only 4% of adults are not protected. If you lived in the same household with siblings who had chickenpox, consider yourself protected. Siblings will come down with chickenpox in 14 to 16 days. The second case in a family always has many more chickenpox sores than the first case.

Call Your Child's Physician Immediately If:

  • Some chickenpox sores look infected (yellow pus, spreading redness, red streaks).
  • Your child develops a speckled, red rash.
  • Your child starts acting very sick.

Call Your Child's Physician Within 24 Hours If:

  • A scab looks infected (becomes larger or drains pus). Note: Use an antibiotic ointment on these sores until your child is seen by a physician.
  • The fever lasts over 4 days.
  • The itching is severe and doesn't respond to treatment.
  • 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