1. Skin Prick Tests Are Only Skin Deep
Many different allergy tests have been developed over recent years. No longer must a person endure the dozens of needles of the allergy test of the past. However, the skin prick tests commonly used today are somewhat less reliable than the needle tests of the past and may be used in combination to confirm a positive result. This means you'll only be injected with a few allergens instead of a few dozen, which is better for everyone involved. But the needle test also has its drawbacks as well. You may get a false positive when you are not actually allergic to the substance. Ask your allergist what method he uses while making the appointment and ask what the false positive rate is on that method of testing.
2. Patching the Facts Together
A skin patch allergy test, used when you have a skin reaction to some type of allergen, simply places a patch of the suspected allergen on your skin. Your allergist leaves the patch in place for 24 to 72 hours and then reads the results. This helps him determine the cause of skin reactions such as contact dermatitis. Although there are no needles involved, which is more attractive to some, it is most often not useful for detecting environmental or food allergies, so its results are limited.
3. In Search of Anti-bodies
One type of allergy test looks for anti-bodies of certain types in your blood. This involves a quick blood sample and does not require you to fast before hand. What they are searching for is a specific kind of immunoglobulin E (IgE), which is the total amount of that anti-body for that allergen. These blood tests are generally only done on people who for some reason cannot have the skin tests done, but can also be done for people who are looking deeper into food allergies.
4. Other Testing Is Available
Some other allergy tests your doctor might prescribe are the immunoassay capture test (ImmunoCAP, UniCAP or Pharmacia CAP) or radioallergosorbent testing (RAST). These tests simply provide more information as to what you might be allergic to and are especially useful in cases where the allergen is evasive. Your doctor will prescribe the right allergy test for your situation.
5. The End Result
In most cases, the result of the allergy test is food avoidance or allergy shots, otherwise called immunotherapy. Only your doctor knows which is right for your type of allergies and what would benefit you most.
