What Is Allergy Testing?
Allergy testing is a form of medical examination that physicians use to determine if you have allergies. An allergy is an overreaction by your immune system to something in the environment that you touch, breathe in, or ingest. There is a broad range of potential allergens, meaning substances to which people can be oversensitive. Allergy tests work by exposing patients to minute amounts of allergens, and documenting the adverse reactions.
Allergies are a common form of illness. It is estimated that as many as 50 million Americans may suffer from some type of allergy. Symptoms range from moderate to severe. In rare cases, allergies can lead to anaphylactic shock and death. If you or a loved one are dealing with allergy symptoms, see your Baptist Health physician for consultation and treatment.
What Types of Allergy Testing Are There?
There are two primary forms of allergy testing: skin tests and blood tests. Elimination diets are sometimes utilized as well.
Allergy Skin Tests
Skin tests are the most common form of allergy testing. Your physician will prepare you for a skin test by asking you questions about your symptoms and compiling your health record and family medical history. He or she may also request that you temporarily stop taking medications which can bias test results. Included are antihistamines, heartburn medications, asthma drugs, and certain antidepressants. A testing appointment will be scheduled, most likely at your physician’s office.
The three types of allergy skin tests are:
- Skin prick test: The nurse overseeing the test will sterilize skin on your back or arm with alcohol. He or she will then prick your skin with small lancets, each containing tiny amounts of allergy material, including plant and tree pollens, molds, dust mites, pet residues, and foods. You may be tested for as many as 40 allergens in one sitting. Two additional substances, histamine and saline, will be utilized as checks on the test, to make sure that your skin is responding in a manner consistent with good results. After 15 or 20 minutes, the nurse will look for obvious signs of irritation and raised, red patches, called wheals, where the lancets have left the allergens. Marks like these will indicate an allergic reaction to particular substances. The bigger the mark, the more serious the allergy.
- Skin injection test: One alternative to a skin prick test is the injection test. Rather than scratch your skin with a lancet, your physician may choose to have trace amounts of the allergen injected below the skin’s surface.
- Patch test: With this test, allergens are applied by patches rather than lancets or needles. You’ll wear the patch for 48 hours before it is removed. Patch tests are used for delayed-response reactions, most frequently seen with various forms of contact dermatitis. The substances tested include latex, metals, fragrances, dyes, and resins.
On completing a test, your physician will explain the results. Though skin tests aren’t perfect indicators of allergic conditions, they often provide the basis for an effective diagnosis. Your physician will discuss the treatment options that are available in your situation.
Allergy Blood Tests
Though skin tests rarely produce severe reactions, your physician may order an allergy blood test if he or she thinks an adverse response is possible. A blood test requires a blood draw, which goes to a medical laboratory for analysis. The analyst will be looking for immunoglobulin E (IgE) antibodies in your sample, which will indicate your body’s predisposition to respond negatively to certain allergic substances.
A third form of testing, called an elimination diet, is sometimes used with food allergies. Your physician will develop a schedule for removing and returning certain foods from and to your diet, monitoring your body’s response with each change.
What Are the Side Effects of Allergy Testing?
Because allergy testing brings you into contact with only very small quantities of an allergen, it is typically quite safe. It is possible, however, that more a severe reaction could occur. A variety of symptoms are possible, up to and including anaphylaxis. In case of a severe reaction, contact your physician immediately. Anaphylaxis should be treated as a medical emergency.
Learn More About Allergy Testing from Baptist Health
If you think that you’ve developed an allergy, let the caring professionals at Baptist Health track down the culprit.