The Basics of Patch Testing for Food Allergies

It’s no secret that childhood allergies are on the rise. Patch testing is a common form of allergy testing that may be suggested by a child’s doctor as he or she works to diagnose the root of a child’s allergies.

Different than a blood test, in which blood is drawn, actual food is used to test how a child’s body reacts to its presence.  Foods tested typically include those in which the child has a history of reactions or may have tested positive for during other types of allergy testing. Typically, the foods are pureed and placed in small metal chambers. These chambers are securely taped to the child’s back so that they are in contact with the skin. The chambers are left in place for 48 hours.

After 48 hours, the patches can be removed at home, and after 72 hours from the placement of the patches, the patient returns to the doctor’s office to have the results “read” by the allergist.  The skin is examined for any reaction. While a reaction to the test does not always mean that the patient is allergic to the specific allergen, it does provide a guide for foods that may be causing the child’s allergic reactions.

Related articles:

  • Food allergies in children: What parents need to know
    An increasing number of children are being diagnosed with food allergies. Today, an estimated 10% of children have some sort of food allergy. This translates to one in 13 children, ...
  • Dealing with Food Allergies Around the Holidays
    The holiday season is a festive time, but can present unique challenges for children with food allergies and their parents. We spoke to Vanessa Chrisman, a clinical pediatric dietitian at ...
  • Kids and Living with Food Allergies
    A food allergy usually occurs in the first two years of life, says Dr. Ellis, a CHOC Allergy and Immunology Specialist. “It’s important to know that allergic reactions to food ...