What Are Allergies?

Allergies are hypersensitivities that involve reactions of the immune system to substances that do not cause reactions in most people. The substances that trigger the reaction are called allergens. These can be something you eat, inhale into your lungs, inject into your body, or touch.

Examples of potential allergens include plants, insect venoms, dander from pets, mold spores, materials, foods, and drugs. They can trigger diverse symptoms that range from mild to severe. Allergic reactions can cause coughing, sneezing, hives, rashes, itchy eyes, runny nose, scratchy throat, low blood pressure, breathing difficulty, asthma attacks, and even death if not treated an anaphylactic reaction occurs.

Several types of tests can be used to determine whether you are allergic to a specific substance. Because there are diverse kinds of allergens, appropriate testing is important to identify and manage allergies.

More Allergy Tests

Getting Tested for Allergies

Allergy testing is almost always performed in a controlled medical setting like a doctor’s office or hospital. Allergen exposure can provoke serious reactions that may be unpredictable. As a result, skin tests and oral food challenges require careful protocols to limit severe reactions — and to quickly and effectively respond if they occur.

Blood testing does not involve allergen exposure and does not have the same risk of reaction. In most cases, a blood sample is taken from your arm with a needle in a medical office and then sent to a laboratory for analysis.

For both skin or blood testing, tests are normally ordered by a doctor based on your past symptoms, allowing the testing to focus on a specific allergen or set of allergens. It is important for anyone with concerns about allergies to talk to their doctor about tests that may be most beneficial in their situation.

Costs of allergy testing

The cost of an allergy test depends on how comprehensive the panel is, along with how and where the test is performed. Insurance can cover allergy testing that is performed in a doctor’s office, laboratory, or other professional health care setting. Talk to your doctor about the cost and payment options before testing.

Types of sample collection

The sample for an allergy test will depend on the particular test you’re taking. The most common ways for testing allergies are by a skin prick test, also referred to as a puncture or scratch test that is usually performed on the forearm or back. Blood testing can also test for allergies, and this requires a needle blood drawn from a vein, usually in the arm.

Getting test results

Allergy test results are usually reviewed with the doctor and in many cases with an allergist. Test results alone often aren’t enough to demonstrate an allergy. Instead, they are typically considered together with past allergic reactions.

Depending on the test results and your history, your doctor might recommend more than one test to confirm or rule out an allergy.


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