Definition

• Allergic reaction to a food

Health Information

Symptoms

• Widespread hives and facial swelling is the most common symptom. Hives are raised pink bumps with pale centers (welts). They look like mosquito bites.
• Mouth itching and swelling
• Runny nose and coughing
• Vomiting and diarrhea.
• Life-threatening allergic reactions must include trouble breathing and/or swallowing. The medical name is an anaphylactic reaction. Most have a sudden onset within 10 to 20 minutes. All start within 2 hours of food exposure. People with anaphylactic reactions carry an emergency kit like Epi-Pen.

Causes

• 8 foods cause 90% of food allergies
• In the first year of life: cow’s milk, soy milk and egg
• Older children: peanuts, tree nuts, fish, shellfish and wheat
• Shellfish include shrimp, crab, lobster, clams, oysters and scallops
• Tree nuts include all the nuts (such as almonds and cashews) except peanuts.
• Of children with a proven food allergy, 40% have severe reactions. The other 60% do not.
• Peanuts and tree nuts are the most common triggers for severe allergic reactions.

Cross Reactions With Other Foods

Children with allergies below can react to other foods:

• Cow’s milk allergy: 90% react with goat’s milk and 40% with soy milk
• Egg: 5% with chicken
• Peanut: 5% with other legumes (like peas or beans). About 30% also react to tree nuts.
• Tree nut: 40% with other tree nuts
• Fish: 50% with other fish. Only 10% also react to shellfish.
• Shellfish: 70% with other shellfish
• Melon: 90% with banana and avocado

How Long do Food Allergies Last?

• Cow’s milk: 80% outgrown by age 16
• Soy milk: 80% by age 16
• Egg: 70% by age 16
• Peanut: 20% by age 16
• Tree nut: 10% by age 16

Prevention of Allergic Disease by Diet

• Most allergic diseases such as food allergies, eczema and asthma cannot be prevented.
• Helpful: Breastfeeding only for 4 months or longer
• Not helpful: Diet limits on certain foods for pregnant or breastfeeding women
• Not helpful: Soy formulas instead of cow’s milk
• Not helpful: A delay in starting baby foods past 6 months
• Not helpful: A delay in starting high-risk foods. Examples are peanut butter or eggs.
• Source: AAP (2008)

Care Advice

1. Overview:
   • About 5% of children have food allergies.
   • Most children with new suspected food allergic reactions need to be seen.
   • But, widespread hives as the only symptom can have many causes.
   • If your child is stable, hives usually can be treated at home.
   • Your child can be seen later to decide future risks and best treatment,
   • Here is some care advice that should help.
2. Benadryl:
   • Give Benadryl 4 times per day for hives all over. No prescription is needed.
   • If you only have another allergy medicine at home (but not Benadryl), use that.
   • Use the Benadryl 4 times per day until the hives are gone for 12 hours.
   • Caution: Do not use if age is under 1 year. Reason: Benadryl makes most children sleepy. Give your doctor a call for advice.
3. Cool Bath for Itching:
   • To help with the itching, can also give a cool bath. Do this for 10 minutes.
   • Caution: Avoid causing a chill.
4. Prevention of Future Reactions:
   • Help your child avoid the food that caused the allergic reaction.
   • Read labels on food products carefully.
   • Tell other caregivers and the school staff of your child’s allergy.
   • Join the Food Allergy Network (www.foodallergy.org).
5. What to Expect:
   • Hives from foods usually last just a short time.
   • They often are gone in less than 6 hours.
6. Return to School:
   • Hives cannot be spread to others.
   • Your child can go back to school once feeling better. The hives shouldn’t keep him from normal activities.

Call Your Doctor If

• Trouble breathing occurs
• Trouble swallowing or drooling occurs
• Severe hives not better after 2 doses of Benadryl
• Hives last over 24 hours
• You think your child needs to be seen
• Your child becomes worse

Author: Barton Schmitt MD, FAAP

Copyright 2000-2020 Schmitt Pediatric Guidelines LLC

Disclaimer: This health information is for educational purposes only. You the reader assume full responsibility for how you choose to use it. The information contained in this handout should not be used as a substitute for the medical care and advice of your pediatrician. Listing of any resources does not imply an endorsement.

#AAP