Skin Testing for Allergies
The debate of the accuracy and worth of skin testing for allergies
Jan 9, 2008
Often the first step in creating an allergy health plan is to see an allergist and have a skin (or prick) test done. This is a test to determine what it is exactly that someone is allergic to. There is some debate, however, on the accuracy and the consistency of the results of the testing.
During an allergy skin test, the skin is pricked and a tiny amount of the supposed allergen is put into the skin. Depending on whether the patient has some idea or not of what the possible allergen may be, the number of allergens tested for will vary. Some patients claim this part of the test is painless, others argue that it is very uncomfortable. Results are seen in about 15 to 20 minutes with raised bumps (or wheals) around the site where the allergen was put. If there is no change in the skin, there is no allergy; if there is change, and depending on the size of the wheal, the extent of the allergy can be determined.
The debate exists on the accuracy of the test results. Some people have found that though they test positive for a specific allergen, they never have had an actual reaction to it in daily life. Also, an allergy can be outgrown, but still appear positive on a skin test. Some allergens are more reliable than others on a skin test. Usually a reading from airborne allergens, like pollen, pet dander or dust is more accurate than food allergies.
There is argument that because there are no immunization shots for food allergies, the testing isn’t worthwhile since avoidance is the best measure to take. On the other side of the debate is that a positive skin test result is more definitive than guesswork. Seeing the reaction to the allergen in a safe, controlled environment also shows that the body does react quickly to the allergen. This can be strong evidence to avoid the allergen, because it can literally be seen and if the body reacts this much to the tiny allergen extract, think what will happen if a person eats or comes into contact with a large amount.
The value of allergy testing is something the patient will have to determine. With a specialist’s help, a good allergy health plan can be devised. This can be done, however, without the discomfort of testing especially if a food allergy is suspected. With airborne allergies, though, it is usually a good idea to undergo testing, especially if allergy shots are desired to relieve the allergy.
