Egg Allergy

Talk to a healthcare provider if you or your child have symptoms of an egg allergy. They may refer you to an allergist (immunologist). They’ll ask you questions, including:

• Does anyone else in your biological family have egg or other food allergies?
• Has a healthcare provider ever diagnosed you with food allergies?
• What are your symptoms?
• When do you notice your symptoms start to appear?
• Do you take over-the-counter (OTC) medications to treat your symptoms?
• Do you keep a food journal?

What tests will be done to diagnose egg allergies?

An allergist may use different allergy tests to help diagnose an egg allergy according to your symptoms. These tests may include:

Skin prick (scratch) test

This test exposes your body to small amounts of egg proteins.

Your allergist will first clean a test area of your skin with iodine or alcohol. The test area is usually on your forearm or upper back.

Your allergist will place a droplet of liquid egg proteins on your skin. They then scratch your skin lightly. The droplets will enter your skin through the scratch. You’ll only feel slight discomfort, and you won’t bleed.

In addition to the egg allergens, the allergist will apply a positive and negative control to your skin. Controls help an allergist compare reactions. A positive control usually contains a histamine solution that causes an itchy, raised spot (wheal) on your skin within a few minutes. A negative control usually contains a saline solution that doesn’t cause a response.

After skin testing, you’ll wait 15 minutes. The allergist will then measure any wheals on your skin from the egg test or the controls with a ruler.

A skin prick test takes less than an hour.

Blood test

During a blood test, your allergist will use a thin needle (slightly smaller than the size of a standard earring post) to withdraw a small amount of blood from a vein in your arm. The blood sample goes to a laboratory. The lab adds egg proteins to your blood sample and measures the levels of IgE antibodies in it.

It may take a week or longer to get the results from a blood test.

Graded oral challenge

To definitively diagnose or rule out an egg allergy, your allergist may recommend a graded oral challenge in the office (food challenge).

You’ll eat a small amount of egg during a graded oral challenge. It may be an egg that isn’t thoroughly cooked (like a soft-boiled egg) or a baked egg. Your allergist will then watch to see if you develop a reaction. If you test positive to an unbaked egg, your allergist may recommend a baked egg challenge to see how your body reacts.

A graded oral challenge may take up to four hours.