Allergies are bad! An allergy is the over-reaction of you body to a substance that is otherwise harmless to the non-allergic person.

Allergies are often described as a "body war." An allergic person contacts (i.e. eats, breathes, or touches) )an allergic substance "allergen" (e.g. dust, grass, tree pollen). This contact triggers a "battle." The body releases chemicals "histamines" that cause the body to react with sneezing, itchy, watery eyes and nose and other symptoms. This is the body's ways of trying to fight the "enemy."

Tests for Allergies

• Skin testing - Skin testing is usually considered to be the most accurate and cost effective. Skin testing is performed by placing droplets of potential allergens on to the skin. The skin is then pierced or scratched through that allergen droplet. If the person is allergic, a bump similar to a mosquito bite, will appear. In most cases, if the person does not react to skin testing then "intradermal" testing will be done.
• Intradermal testing - Intradermal testing requires injecting allergen under the skin. This test works the same way as the skin testing, but uses a stronger from of the allergen.
• Radi-allergosorbent Testing (RAST) - Radio-allergosorbent Testing (RAST) is a blood test for allergies. This test measures IgE in the blood. IgE is a chemical in the body that reacts with an allergen to cause an allergic reaction. IgE must be present to be classified as an "allergic response." The level of the IgE for each allergen in the body can be measured. When the IgE reacts with the specific allergen, the combination activates the allergy cell (mast cell). This type of testing is more expensive and less reliable that skin testing. However, it should be used when a person has a rash that would interfere with the reading of the skin test, when a person cannot tolerate multiple injections or cannot stop taking their antihistamine prior to the skin testing.