Food Allergy

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Symptoms of Food Allergies

• Hives all over and swelling of the face are the most common symptoms. Hives are raised pink bumps with pale centers (welts). They look like bug bites.
• Mouth itching and swelling
• Runny nose and coughing
• Vomiting and diarrhea
• Life-threatening allergic reactions also must have trouble breathing and/or swallowing. The medical name for this is anaphylaxis. Most of these reactions have a sudden onset within 10 to 20 minutes. All occur within 2 hours of eating a certain food. People who have had this carry an emergency kit like an Epi-Pen.

Causes of Food Allergies

• 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% have mild reactions.
• Peanuts and tree nuts are the most common triggers for severe reactions.

Cross Reactions with Other Foods

Children with allergies listed below can react to other foods:

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

Allergic Disease - Can You Prevent with Diet?

• Most allergic diseases (food allergies, eczema and asthma) cannot be prevented.
• Helpful: feeding only breastmilk for 6 months or longer
• Not helpful: avoiding high-risk foods for pregnant or breastfeeding women
• Not helpful: soy formulas instead of cow's milk formula
• Not helpful: a delay in starting baby foods past 6 months
• Not helpful: a delay in starting high-risk foods like peanut butter or eggs
• Source: AAP

Oral Allergy Syndrome (OAS)

• A minor reaction to some raw fruits and veggies
• Causes itching and swelling only to the lips and tongue
• Also called Pollen-Food Syndrome

Symptoms of OAS

• Rapid onset of itching (or tingling) and swelling of the mouth.
• This can involve the lips, tongue, throat, and roof of the mouth.
• The uvula (tag of tissue hanging down in back) can become very swollen.
• These symptoms follow eating a high-risk raw fruit or veggie.
• OAS can start by age 5.
• Serious symptoms or very bad reactions rarely happen.

Causes of OAS

• A contact allergy. It only involves the parts of the mouth that touch the raw food.
• Trigger foods for OAS are always raw (not cooked.)
• Fresh Fruits. These include apple, apricot, banana, cherry, melons, orange, peach and pear.
• Raw Veggies. These include carrot, celery, parsley, potato and tomato. Carrots and celery have the highest risk for also causing serious symptoms.
• Certain Seeds. These include sunflower seeds and fennel seeds.

OAS and Nose Allergies Can Be Linked

• Over 50% of people who are allergic to pollen also have OAS. This means 10% of all people.
• Ragweed pollen allergy can cross-react with all melons. Also, sometimes with bananas and tomatoes.
• Birch pollen allergy can cross-react with raw potatoes, carrots, celery and apples.
• Grass pollen allergy can cross-react with tomato and kiwi.

When to Call for Food Allergy

Care Advice

Treatment of a Food Allergy

What You Should Know About Food Allergies:

• About 5% of children have food allergies.
• Most children with a new food reaction need to be seen.
• If your child is stable, hives often can be treated at home.
• Hives as the only symptom can have many causes.
• Your child can be seen later to decide future risks and best treatment.
• Here is some care advice that should help.

Allergy Medicine for Hives:

• Give Benadryl 4 times per day for hives all over. Age limit: 1 and older.
• Use the allergy medicine until the hives are gone for 12 hours.
• If the hives last more than a few days, switch to a long-acting antihistamine, such as Zyrtec. No prescription is needed. Age limit: 6 months and older.
• Zyrtec dosing for 6 months to 2 years: 2.5 mL (2.5 mg) every 24 hours.
• Zyrtec dosing for 2 years and older: follow package directions.

Cool Bath for Itching:

• To help with any itching, can also give a cool bath. Do this for 10 minutes.
• Caution: do not cause a chill.

How to Prevent Future Reactions:

• Help your child avoid the food that caused the symptoms.
• Read labels on all food products fully.
• Tell other people who care for your child of your child's food allergy. Also, inform the staff at your child's school.

What to Expect:

• Hives from foods often last just a short time.
• They often are gone in less than 6 hours.

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 doing normal things.

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

Treatment of Oral Allergy Syndrome Symptoms

What You Should Know:

• Oral Allergy Syndrome (OAS) is very common. It happens in 10% of people. Most of them also have pollen allergies.
• The symptoms are not harmful and can be treated at home.
• Needed for OAS: your child has never had any serious symptoms with this food.
• OAS symptoms don't last very long.
• Here is some care advice that should help.

Rinse the Mouth:

• Rinse the lips and mouth with warm water. Do this a few times.
• Reason: to remove any traces of the food.

Cold Pack:

• Use ice or a cold pack to the swollen lips or tongue for 10 minutes.
• Reason: to lessen the swelling and the itch.

Allergy Medicine:

• One dose of Benadryl may help the symptoms go away faster.
• No prescription is needed. Age limit: 1 or older.

How to Prevent Future OAS:

• Keep a list of the foods that cause your child's symptoms.
• Avoid these foods if they are raw (fresh).
• The cooked version of these foods usually won't cause any symptoms.

What to Expect:

• With or without treatment, the itching will go away in 1 to 2 hours.
• The mouth swelling will also go away quickly.

Call Your Doctor If:

• Trouble swallowing or drooling occurs
• Trouble breathing occurs
• Swelling or rash occurs anywhere else
• You think your child needs to be seen
• Your child becomes worse

Remember! Contact your doctor if you or your child develop any "Contact Your Doctor" symptoms.

Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.