Different Types of Allergy Tests and How They Work
If your primary care physician suspects that you may have allergies, they may suggest doing an allergy test. Your allergic reaction can range from mild symptoms such as itchiness or a rash to severe symptoms such as the constriction of your airway resulting in a visit to the emergency department. Taking an allergy test can help identify some of the allergens that you may not know about, allowing you to avoid such allergens in the future. Knowing what you are allergic to and avoiding such allergens, it will save you a scary trip to the emergency department and uncomfortable reactions from your allergies.
Prick and Intradermal Allergy Skin Tests
The most common allergy tests are the prick and intradermal allergy skin tests. It can help identify suspected seasonal, environmental, insects, food, and medication allergies. To perform the prick allergy skin test, a pricking device is used to place the allergen on the skin. To perform the intradermal allergy skin test, a solution containing the allergen is placed just below the skin by a small needle.
Blood Tests for Allergies
Blood tests for allergies are used for patients that cannot stay off their antihistamines and other medications long enough to do a skin testing. Another reason for taking a blood test over an allergy skin test is when the patients have hives, lesions, or rashes that may interfere with skin testing. The most common blood tests is IgE tests or RAST tests.
Food and Drug Challenge Tests
Food and drug challenge tests are used for those who may be allergic to food or drug. The patient is given a small dose of food or drugs that may cause allergic symptoms. The patient is supervised by a physician to assess for any allergic reaction between the small doses.
Patch Allergy Testing
Patch allergy testing is used for patients with contact dermatitis. The test can help to identify any underlying trigger to contact dermatitides such as skin care products, soap, detergent, or metal jewelry. The test requires wearing a patch on the patient’s back with the suspected allergen for 48 hours. After 48 hours, the skin under the patch is evaluated for signs of contact dermatitis.
