Clinical Reference Systems: Pediatric Advisor 10.0
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Definition

• Tiny, pink bumps
• Occasionally, some are pinpoint-size water blisters
• Mainly on neck and upper back or chest
• Occurs during hot, humid weather
• Heat rash can be itchy
• Older children report a "prickly" pins and needles sensation
• No fever or sickness
• Also called "prickly heat."

Cause

Heat rash is caused by blocked-off sweat glands. Lots of children get it during hot, humid weather when sweat glands are overworked. Infants can also get it in the wintertime with fever, overdressing, or ointments applied to the chest for coughs (ointments block off the sweat glands). Older children can get it with exercise.

Expected Course

With treatment, heat rash usually clears up completely in 2 to 3 days.

Home Care

1. Cooling.

   Use techniques that cool off the skin:

   • Give cool baths every 2 to 3 hours, without soap. Let the skin air-dry.
   • For localized rashes, apply a cool, wet washcloth to the area for 5 to 10 minutes.
   • Dress your child in as few layers of clothing as possible.
   • Lower the temperature in your home or use a fan when your child is asleep.
   • Have the child lie on a cotton towel to absorb perspiration.

2. Hydrocortisone cream.

   Apply 1% hydrocortisone cream (no prescription necessary) 3 times a day to itchy spots. Avoid hydrocortisone ointments. Calamine lotion is another option.

3. Avoid ointments.

   Avoid all ointments or oils because they can block off sweat glands. Be sure the rash isn't caused by a mentholated ointment being used for a cough.

Call Your Child's Physician During Office Hours If:

• The rash lasts more than 3 days on this treatment.
• You have other concerns or questions.