Since children’s food allergies can resolve, parents may wonder if, or how often they should have a child retested for their allergies. Allergy retesting is a bit like checking to see which way the wind is blowing. It lets doctors and parents know whether an allergy might be heading toward resolution. If the results of a child’s skin and blood tests get smaller or decline over time, it’s a sign that the allergy may eventually be outgrown.
The timing of allergy retesting, according to allergist and clinical researcher Dr. Scott Sicherer, depends on several factors including the child’s age, medical history, past test results, and the problematic foods. For instance:
- Test results can change more quickly during a child’s infant and preschool years, so more frequent testing might be suitable. Earlier tests that were low or diminishing could warrant re-checking sooner than usual.
- It makes sense to test more often for food allergies that frequently resolve at early an age, such as egg, milk, soy, and wheat. Less frequent testing is generally done for the more persistent allergies, including peanut, tree nuts, shellfish, and fish.
- An accidental ingestion of an allergen that results in a reaction indicates the allergy is persisting and would suggest that re-testing be delayed. Accidental ingestion without a subsequent reaction would naturally recommend re-testing sooner instead of later.
- Generally, kids might be tested every six to 12 months during their first two years, then annually after that—unless there are modifying factors. A toddler with milk and wheat allergies, for example, might be re-tested after one year, but an adolescent with a shellfish allergy might get tested every two or more years.
Dr. Sicherer recommends seeing an allergist annually to evaluate and update a child’s allergy management plan, making sure it remains relevant to his or her changing needs.
The doctor might, for instance, want to review your child’s emergency plan, update epinephrine auto-injector prescriptions, review auto-injector use, or make sure allergen avoidance is not interfering with the child’s nutritional needs. An annual visit is also a good time to discuss retesting, and new allergy guidelines or treatments.