Allergy skin testing is the preferred method, but in some cases blood testing may be ordered. Allergy blood testing is recommended if you: Are using a medicine known to interfere with test results and cannot stop taking it for a few daysl this would include antihistamines, steroids, and certain antidepressants.
In this case, he or she may recommend an oral food challenge (OFC). This is a highly accurate diagnostic test for food allergies. Safety of Oral Food Challenges. Because this test can cause a serious allergic reaction, only an experienced allergist should conduct it. It should happen at a medical facility with the appropriate medications and equipment.