Learn About Allergy Lab Tests

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What Are Allergies?

Over 50 million Americans suffer from allergies. So, what are they? Allergies are anything that a person’s body has a negative reaction to. This can be anything from peanuts and shellfish, to dust and pollen; allergies take many different forms and are different for every sufferer. When a person comes in contact, or ingests something they are allergic to, it causes the immune system to go into defense mode. This is also known as having an allergic reaction. The immune system begins to attack the object that a person’s body deems to be unknown, or foreign. This will cause the person to have a range of effects such as itching, sneezing, runny nose, cough, rash, swelling of the body, swelling of the throat, and even breathing problems. In serious cases, the outcome of an allergic reaction can result in death.

Since allergies range in severity it is very important for a person to know and understand what they are allergic to. Knowing this information will help a person avoid these things, and will keep them from having an unwanted reaction. There are ways to learn what objects you are allergic to. Making an appointment with your doctor is the first step. During your initial appointment your doctor will talk to you about allergies and will tell you all about allergy lab tests as a way to find your exact allergy triggers. The next step will be seeing an allergist, and going to an allergy lab for further testing and diagnosis.

Allergy Testing

There are different ways a lab tech will perform an allergy test; one way is a skin test and the other is a blood test. Your allergist may prescribe one of these, or both of these for your testing.

The simplest form of allergy testing is a blood test. Although using a blood test to diagnose a person’s allergy triggers is not as sensitive as other testing methods (meaning it may not pick up all types of allergens in the blood), it is the ideal test for those that are unable to have skin testing performed. A blood test will look for certain antibodies in the blood stream and will measure the blood level of the antibody that the body produces when in contact with allergens.

For a more in depth look into what causes your allergies, skin testing will be performed. Unlike a blood test, skin testing will give a quicker and more reliable result. The types of skin tests an allergist may prescribe are a skin prick test, intradermal test, and a skin patch test.

During a skin prick test, a solution containing possible allergens is placed on an area of the skin. That area will then get pricked or scratched with needles, allowing the solution to go into the skin. If a rash develops, this is usually a sign of a positive reaction. The person being tested is more than likely allergic to that allergen.

To perform an intradermal test, a small amount of the allergen solution is injected under the skin to see if a reaction arises. This test is usually preformed in the instance that a skin prick test proves negative on an allergen that is suspected to be a trigger. One downside to this test is the high risk of a false positive result.

For a person that has topical allergens, a skin patch test will be preformed. During this test, a patch covered with an allergen solution is placed onto the skin and held in place for 24 to 72 hours, and then checked for reactions. This test is usually preformed on people with skin allergies.

Depending on a person’s test results, a treatment plan may be necessary. This treatment may consist of allergy medications or an allergy shot. A person with allergies should keep in contact with their care provider since there are always new medications and treatments available for allergy sufferers. For optimal results, it’s best to steer clear of your allergy triggers and take your medications as prescribed.



American College of Allergy, Asthma, & Immunology