Clinical Reference Systems: Pediatric Advisor 10.0
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Hives (Urticaria)

DESCRIPTION

Your child has a very itchy rash.
There are raised pink spots with pale centers on the skin. The spots range from 1/2 inch to several inches wide (hives often look like mosquito bites).
The spots may be have quite variable shapes.
The spots rapidly and repeatedly change in location, size, and shape.

CAUSE

Widespread hives are an allergic reaction to a food, Medicine, viral infection, insect bite, or many other possible substances. Often the cause is not found. Hives on just one part of the body (localized) are usually due to skin contact with plants, pollen, food, or pet saliva. Localized hives are not caused by drugs, infections, or swallowed foods. Hives are not contagious.

EXPECTED COURSE

More than 10% of children get hives. Most children who develop hives have them only once. The hives come and go for 3 or 4 days and then mysteriously disappear.

Large swellings are common around the eyes, lips, and genitals if hives occur there.

Some young children become sensitized to mosquito or flea bites. They develop big hives (called papular urticaria) at the sites of old and new bites. These hives may last for months.

HOME TREATMENT

  1. Antihistamine medicine

    The best drug for hives is an antihistamine. An antihistamine won't cure the hives, but it will reduce their number and relieve itching.

    Benadryl, one of the most commonly used drugs for hives, has recently become available without a prescription. The main side effect of this drug is drowsiness. If you have another antihistamine (for example, any drug for hay fever) at home, use it until you can get some Benadryl. When you give Benadryl, give it four times a day in the following doses: 

     
                       Child's Weight (pounds) 
                20    40    60     80     100    120 
    -------------------------------------------------------
    Liquid (ml)  3     6    10     13      16     20  
    Tablets      -     -     1      1    1+1/2    2 
    -------------------------------------------------------
    Notes:  Concentration of Benadryl liquid:  12.5 mg/5 ml. 
            Benadryl tablets are 25-mg tablets.

    Use the drug recommended by your child's physician.

  2. Itching

    Give a cool bath to relieve itching. Rub very itchy areas with a cold washcloth or ice cube for 10 minutes.

  3. Avoidance and showers

    Avoid anything you think might have caused the hives. For hives triggered by pollen or animal contact, take a cool shower or bath. For localized hives, wash the allergic substance of the skin with soap and water. Localized hives usually disappear in a few hours and don't need Benadryl.

  4. Common mistakes in the treatment of hives

    Many parents wait to give the antihistamine until new hives have appeared. This means your child will become itchy again. The purpose of the medicine is to keep your child comfortable until the hives go away. Therefore, give the medicine regularly until you are sure the hives are completely gone.

    Hives are not contagious and your child can be with other children.

CALL YOUR CHILD'S PHYSICIAN IMMEDIATELY IF:

Breathing or swallowing becomes difficult.
Your child starts acting very sick.

CALL YOUR CHILD'S PHYSICIAN DURING OFFICE HOURS IF:

Most of the itch is not relieved after your child has been taking an antihistamine for 24 hours.
Most of the itch is not relieved after 24 hours on continuous Benadryl.
The hives last more than 1 week.
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