Allergy skin tests are a common way to diagnose allergies. They involve exposing the skin to a small amount of an allergen and then observing the skin for signs of an allergic reaction. Knowing what to expect before, during, and after an allergy skin test can help you prepare for the procedure and understand the results.
What is an allergy skin test?
An allergy skin test is a procedure used to determine if a person is allergic to a particular substance. During the test, a small amount of an allergen (such as pollen, dust, or pet dander) is placed on the skin. The skin is then observed for signs of an allergic reaction, such as redness, swelling, or itching.
Are there different kinds of allergy skin tests?
Yes, there are three types of allergy skin tests: skin prick (scratch) test, intradermal test, and patch test.
Skin Prick (Scratch) Test
The skin prick (scratch) test is the most common type of allergy skin test. During the test, a small amount of the allergen is placed on the skin and then a needle is used to prick the skin. The skin is then observed for signs of an allergic reaction.
Intradermal Test
The intradermal test is similar to the skin prick test, but a small amount of the allergen is injected into the skin instead of being placed on the skin. The skin is then observed for signs of an allergic reaction.
Patch Test
The patch test is used to diagnose contact allergies. During the test, a patch containing the allergen is placed on the skin and left in place for 48 hours. The skin is then observed for signs of an allergic reaction.
When is an allergy skin test performed?
An allergy skin test is usually performed when a person has symptoms of an allergic reaction, such as sneezing, itching, or hives. The test can help determine what is causing the allergic reaction.
How accurate is allergy skin testing?
Allergy skin tests are generally considered to be very accurate. However, false-positive and false-negative results can occur.
What should I expect before an allergy skin test?
Before an allergy skin test, you should tell your healthcare provider about any medications you are taking, as some medications can interfere with the results of the test. You should also avoid taking antihistamines for at least three days before the test.
Should I shower before or after a skin allergy test?
It is recommended that you shower before a skin allergy test to remove any lotions, creams, or other substances that may interfere with the results of the test.
What should I expect after an allergy skin test?
After an allergy skin test, you may experience some redness, swelling, or itching at the site of the test. This is normal and should go away within a few hours.
What are the risks of an allergy skin test?
Allergy skin tests are generally considered to be safe. However, there is a risk of a severe allergic reaction (anaphylaxis) in rare cases.
When should I get my skin allergy test results?
Your healthcare provider should be able to provide you with your allergy skin test results within a few days.
What do allergy skin test results mean?
Allergy skin test results can help your healthcare provider diagnose allergies and determine the best treatment plan for you.
What are false-positive and false-negative allergy skin test results?
False-positive results occur when a person tests positive for an allergy even though they are not actually allergic to the substance. False-negative results occur when a person tests negative for an allergy even though they are actually allergic to the substance.
When should I call a healthcare provider?
If you experience any signs of a severe allergic reaction (such as difficulty breathing, swelling of the face or throat, or dizziness) after an allergy skin test, you should call your healthcare provider immediately.
Does insurance cover allergy skin tests?
Most insurance plans cover allergy skin tests. However, you should check with your insurance provider to make sure the test is covered.
References
- American College of Allergy, Asthma & Immunology. (n.d.). Allergy skin tests. Retrieved from https://acaai.org/allergies/types/skin-allergy-tests
- Mayo Clinic. (2020). Allergy skin tests. Retrieved from https://www.mayoclinic.org/tests-procedures/allergy-skin-test/about/pac-20384610
- U.S. National Library of Medicine. (2020). Allergy skin tests. Retrieved from https://medlineplus.gov/ency/article/003420.htm
Keywords: allergy skin test, skin prick test, intradermal test, patch test, false-positive results