Allergy Tests: Are They
Really Accurate?
While allergy tests are recommended as the
only sure way to isolate individual triggers and successfully treat
symptoms, there is some question about just how accurate these tests really
are. In fact, since there is such a wide range of reactions and symptoms can
vary from one individual to another, it can be difficult to gauge the
accuracy of test results.
In general, the accuracy of results will depend on the individual being
tested and the type of allergen being tested for. Skin prick tests,
intradermal tests and patch tests, for example, will be accurate for
airborne or contact allergens but will not work for food allergies or
allergies to most medications. These types of allergies will require a blood
test or another form of testing for the best results.
Skin prick tests apply a small amount of a suspected trigger to an isolated
patch of skin. After 15 minutes or so, if the substance is a trigger, a
reaction will occur. These tests are most accurate for pollen, dust and
insect bites. Up to 40 substances can be tested at one time with this
method, but usually the total is far fewer.
Other types of skin test, including intradermal and patch, are also geared
manly toward contact or airborne allergens and are usually pretty accurate.
Accuracy of any test will depend heavily on the doctor or nurse performing
it. Only trained personnel should administer these types of tests as some
allergic reaction can occur as a result so they need to be carefully
monitored.
For reactions to food or particular medications, other types of testing will
be necessary. These can include blood testing and hair analysis. These types
of tests take longer to produce results but generally do not cause any
unpleasant side effects. Because results are produced in a laboratory
setting, results are normally quite accurate.
The main difficulty with determining the accuracy of testing is that
reactions can vary from individual to individual and further, your reaction
to a particular substance can sometimes change over time. This is why some
people talk about “outgrowing” their allergies. As the body matures and the
immune system develops, the response to trigger substances can be naturally
reduced.
Often, you may have a positive response for a substance when tested that you
have never had a problem with before or sometimes you can have a negative
result and yet still react to that substance when not in a test situation.
None of the tests is one hundred percent accurate, but they are still
considered the single best way of determining susceptibility to a particular
trigger or triggers.
Many people are leery of being tested, as they don’t believe the tests will
actually work, but having any information, however tenuous, is still better
than blindly guessing. At least with a direction to point in, you can have a
better idea of what type of treatment to use to lessen your symptoms.
Wishing you the best of health
The Allergy Store