Overview

Eggs are one of the most common allergy-causing foods for children.

Egg allergy symptoms usually occur a few minutes to a few hours after eating eggs or foods containing eggs. Signs and symptoms range from mild to severe and can include skin rashes, hives, nasal congestion, and vomiting or other digestive problems. Rarely, egg allergy can cause anaphylaxis — a life-threatening reaction.

Egg allergy can occur as early as infancy. Most children, but not all, outgrow their egg allergy before adolescence.

Symptoms

Egg allergy reactions vary from person to person and usually occur soon after exposure to egg. Egg allergy symptoms can include:

  • Skin inflammation or hives — the most common egg allergy reaction
  • Nasal congestion, runny nose and sneezing (allergic rhinitis)
  • Digestive symptoms, such as cramps, nausea and vomiting
  • Asthma signs and symptoms such as coughing, wheezing, chest tightness or shortness of breath

Anaphylaxis

A severe allergic reaction can lead to anaphylaxis, a life-threatening emergency that requires an immediate epinephrine (adrenaline) shot and a trip to the emergency room. Anaphylaxis signs and symptoms include:

  • Constriction of airways, including a swollen throat or a lump in your throat that makes it difficult to breathe
  • Abdominal pain and cramping
  • Rapid pulse
  • Shock, with a severe drop in blood pressure felt as dizziness, lightheadedness or loss of consciousness

Discuss with your doctor any reaction — no matter how mild — you or your child has to eggs. The severity of egg allergy reactions can vary each time one occurs, so even if a past reaction was mild, the next one could be more serious.

If your doctor thinks you or your child may be at risk of a severe reaction, he or she may prescribe an emergency epinephrine shot to be used if anaphylaxis occurs. The shot comes in a device that makes it easy to deliver, called an autoinjector.

When to see a doctor

See a doctor if you or your child has signs or symptoms of a food allergy shortly after eating eggs or an egg-containing product. If possible, see the doctor when the allergic reaction is occurring. This may help in making a diagnosis.

If you or your child has signs and symptoms of anaphylaxis, seek immediate emergency treatment and use an autoinjector if one has been prescribed.

Causes

An immune system overreaction causes food allergies. For egg allergy, the immune system mistakenly identifies certain egg proteins as harmful. When you or your child comes in contact with egg proteins, immune system cells (antibodies) recognize them and signal the immune system to release histamine and other chemicals that cause allergic signs and symptoms.

Both egg yolks and egg whites contain proteins that can cause allergies, but allergy to egg whites is most common. It's possible for breast-fed infants to have an allergic reaction to egg proteins in breast milk if the mother consumes eggs.

Risk factors

Certain factors can increase the risk of developing an egg allergy:

  • Atopic dermatitis. Children with this type of skin reaction are much more likely to develop a food allergy than are children who don't have skin problems.
  • Family history. You're at increased risk of a food allergy if one or both of your parents have asthma, food allergy or another type of allergy — such as hay fever, hives or eczema.
  • Age. Egg allergy is most common in children. With age, the digestive system matures and allergic food reactions are less likely to occur.

Complications

The most significant complication of egg allergy is having a severe allergic reaction requiring an epinephrine injection and emergency treatment.

The same immune system reaction that causes egg allergy can also cause other conditions. If you or your child has an egg allergy, you or your child may be at increased risk of:

  • Allergies to other foods, such as milk, soy or peanuts
  • Allergies to pet dander, dust mites or grass pollen
  • Allergic skin reactions such as atopic dermatitis
  • Asthma, which in turn increases the risk of having a severe allergic reaction to eggs or other foods

Prevention

Here are some things you can do to avoid an allergic reaction, and to keep it from getting worse if one does occur.

  • Read food labels carefully. Some people react to foods with only trace amounts of egg.
  • Be cautious when eating out. Your server or even the cook may not be completely certain about whether a food contains egg proteins.
  • Wear an allergy bracelet or necklace. This can be especially important if you or your child has a severe reaction and can't tell caregivers or others what's going on.
  • Let your child's caregivers know about an egg allergy. Talk to your child's babysitters, teachers, relatives or other caregivers about the egg allergy so that they don't accidently give your child egg-containing products. Make sure they understand what to do in an emergency.
  • If you're breast-feeding, avoid eggs. If your child has an egg allergy, he or she may react to proteins passed through your milk.

Hidden sources of egg products

Unfortunately, even if a food is labeled egg-free it may still contain some egg proteins. When in doubt, contact the manufacturer.

Foods that contain eggs can include:

  • Marshmallows
  • Mayonnaise
  • Meringue
  • Baked goods
  • Breaded foods
  • Marzipan
  • Frostings
  • Processed meat, meatloaf and meatballs
  • Puddings and custards
  • Salad dressing
  • Many pastas
  • Foam on alcoholic, specialty coffees
  • Pretzels

Several terms indicate that egg products have been used in manufacturing processed foods, including:

  • Albumin
  • Globulin
  • Lecithin
  • Livetin
  • Lysozyme
  • Vitellin
  • Words starting with "ova" or "ovo," such as ovalbumin or ovoglobulin

Another potential source of exposure is cross-contamination in home-prepared dishes or meals, especially when you're eating in other people's homes where they may not be aware of the risk.

Vaccinations and egg allergy

Some shots to prevent illness (vaccines) contain egg proteins. In some people, these vaccines pose a risk of triggering an allergic reaction.

  • Measles-mumps-rubella (MMR) vaccines are generally safe for children with egg allergy, even though eggs are used to produce them.
  • Flu (influenza) vaccines sometimes contain small amounts of egg proteins. However, a flu vaccine that doesn't contain these proteins is approved for use in adults age 18 and older. And even vaccines that do have egg proteins can be given safely to most people with egg allergy without any problems. If you or your child has had a reaction to eggs in the past, talk to your doctor before getting a flu vaccination.
  • Yellow fever vaccine can provoke an allergic reaction in some people who have egg allergy. It's given to travelers entering countries where there's a risk of contracting yellow fever. It's not generally recommended for people with egg allergy, but is sometimes given under medical supervision after testing for a reaction.
  • Other vaccines are generally not risky for people who have egg allergy. But ask your doctor, just to be safe. If your doctor is concerned about a vaccine, he or she may test you or your child to see whether it is likely to cause a reaction.
Jan. 27, 2015
References
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