Daily Q & A

Allergy skin tests

For more than a century, doctors have used skin tests to help diagnose allergies. During these tests, your skin is exposed to allergy-causing substances (allergens) and then is observed for signs of an allergic reaction. Along with your medical history, skin tests can confirm whether signs and symptoms, such as sneezing, wheezing and skin rashes, are caused by allergies. They can also identify the specific substances that trigger allergic reactions. Such information can help your doctor develop an allergy treatment plan that may include allergen avoidance, medications or allergy shots (immunotherapy).

Allergy test

Allergy Testing: also known as: RAST test, Allergy screen, Formal name: Allergen-specific IgE antibody test. Related tests: Total IgE, Complete Blood Count (CBC), White Blood Cell Differential Count, Eosinophil count, Basophil Count.

How is it used? 

The allergen-specific IgE antibody test is done to screen for an allergy (a type I hypersensitivity) to a specific substance or substances when a patient presents with acute or chronic allergy-like symptoms.
The allergen-specific IgE antibody test may be done (instead of other medically supervised allergy testing) when the patient has significant dermatitis or eczema (also a sign of allergies), is taking necessary histamines or anti-depressants that would make other testing more difficult, or if a dangerous allergic reaction could be expected to follow another test.
The allergen-specific IgE antibody test may also be done to monitor immunotherapy or to see if a child has outgrown an allergy, although it can only be used in a general way; the level of IgE present does not correlate to the severity of an allergic reaction, and someone who has outgrown an allergy may have a positive IgE for many years afterward.

What is Allergy testing?

White Blood Cell Differential Count