Food allergy testing can check for several allergens during one visit. By using a skin prick test or blood test, our Atlanta allergists can see how a patient’s body responds to a range of foods. They will then evaluate those results while considering the patient’s history and symptoms to identify which foods are causing reactions. Here we’ll explain how allergists choose which foods to test, and how the results help patients manage multiple food allergies.
How Allergists Decide Which Foods to Test
Before food allergy testing begins, you and your allergist will have a conversation about what you ate, the nature of your symptoms, how soon after exposure the symptoms started, and how often they occur. They’ll also want to know about any family history involving allergies and related conditions like eczema or asthma. Allergists study these details to decide which foods to test. This keeps testing focused and the results can be evaluated with greater clarity.
Skin Prick Testing for Multiple Food Allergies
Skin prick testing is the most common food allergy test for many reasons. Along with delivering fast results available during the same visit, it also allows allergists to test for multiple allergies in a single session. With skin prick testing, small drops of food extract are placed in a grid layout on the forearm or back. Next, the skin under each allergen drop extract is pricked to allow entry under the skin, and the area is monitored for a reaction.
Blood Testing for Multiple Foods
Blood testing is usually recommended when skin prick testing is not possible due to a skin condition or medication needs. From a single blood draw, the laboratory can check for food-specific IgE antibodies for multiple foods. While a raised level of antibodies does suggest a sensitivity to a food, allergists need to consider this information along with the complete data they have gathered.
Why an Allergy to One Food May Affect Others
Some foods share similar proteins, and allergists factor that in when they use food allergy testing to guide treatment. For example, shellfish like shrimp, crab, lobster, crawfish and prawns can cross-react because they are all crustaceans. Similarly, tree nuts such as cashew and pistachio or walnut and pecan have a strong cross-reactive relationship. Plus, many people (but not all) with tree nut allergies also react to peanuts. Allergists will consider these factors when deciding the allergens to test for.
What Is an Oral Food Challenge?
In some cases, an oral food challenge (OFC) is required to confirm or rule out an allergy. This test may be used when other test results are unclear, or when an allergist wants to determine whether an allergy has been outgrown. During an OFC test, a patient eats gradually increasing amounts of the food while being monitored at their allergist’s office. And unlike other testing options, an oral food challenge will usually require several individual challenges if multiple food allergies are involved.
Managing Multiple Food Allergies
For patients with multiple food allergies, food allergy treatment can be more complicated. After testing is complete, allergists work with individuals and families to create custom allergy management plans. Part of managing multiple food allergies could involve strategies such as reading food labels and asking about allergens when eating at restaurants. Additionally, oral immunotherapy could be an option used to gradually desensitize a patient’s immune system to foods like peanuts and tree nuts.
Access Food Allergy Testing at Our Atlanta-Area Centers
Treating one or more food allergies starts with an accurate diagnosis. Visit us at one of our Atlanta-area food allergy treatment centers for dependable testing and treatment options. To learn more, call (678) 668-4688 or request an appointment.
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