Diagnosis

To diagnose egg allergy, your doctor will use several approaches, including ruling out other conditions that could be causing symptoms. In many cases, what seems to be egg allergy is actually caused by food intolerance, which is generally less serious than food allergy and doesn't involve the immune system.

Your doctor takes a medical history and conducts a physical exam. He or she may also recommend one or more of the following tests:

• Skin prick test. In this test, the skin is pricked and exposed to small amounts of the proteins found in eggs. If you or your child has egg allergy, a raised bump (hive) may develop at the test location. Allergy specialists are generally best equipped to perform and interpret allergy skin tests.
• Blood test. A blood test can measure the immune system's response to eggs by checking the amount of certain antibodies in the bloodstream that may indicate an allergic reaction.
• Food challenge. This test involves giving you or your child a small amount of egg to see if it causes a reaction. If nothing happens, more egg is given while the doctor watches for signs of a food allergy. Because this test can cause a severe reaction, an allergy specialist should give it.
• Food tracking or elimination diet. Your or your child's doctor may have you keep a detailed diary of foods eaten and may ask you to eliminate eggs or other foods from the diet one at a time to see whether symptoms improve.