Eggs are one of the most common allergy-causing foods. Although egg allergy can affect adults, it's more common in children. Most children outgrow their egg allergy by the time they're 5 years old.
Allergic reactions 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, vomiting or inflamed nasal passages. Rarely, egg allergy can cause anaphylaxis — a severe, life-threatening reaction.
Egg allergy signs and symptoms differ from person to person and occur within a few minutes to a few hours after ingesting eggs. Signs and symptoms can include:
- Skin inflammation or hives, the most common egg allergy reaction
- Allergic asthma
- Allergic nasal inflammation (rhinitis)
- Gastrointestinal symptoms, such as cramps, nausea and vomiting
Egg allergy can cause anaphylaxis, a life-threatening reaction that can block the airways and breathing. If you or your child has a reaction to eggs, tell your doctor about it no matter how mild the reaction may have been. Tests can help confirm an egg allergy, so you can take steps to avoid future and potentially worse reactions.
Anaphylaxis is a medical emergency and requires treatment with an epinephrine (adrenaline) shot and a trip to the emergency room. Signs and symptoms start soon after eating eggs and can include:
- Constriction of airways, including a swollen throat or a lump in your throat that makes it difficult to breathe
- Shock, with a severe drop in blood pressure
- Rapid pulse
- Dizziness, lightheadedness or loss of consciousness
What causes it?
All food allergies are caused by an immune system malfunction. Your immune system identifies certain egg proteins as harmful, triggering the production of immunoglobulin E (IgE) antibodies to neutralize the protein (allergen). The next time you come in contact with these proteins, these IgE antibodies recognize them and signal your immune system to release histamine and other chemicals. Histamine and other body chemicals cause a range of allergic signs and symptoms. Histamine is partly responsible for most allergic responses, including runny nose, itchy eyes, dry throat, rashes, hives, nausea, diarrhea, labored breathing and anaphylactic shock.
Both egg yolks and egg whites contain a number of proteins that can cause allergies, but allergy to egg white is more common. Some breast-fed infants have an allergic reaction to egg proteins in breast milk.