What are the allergies?
An allergy is the result of a persons overactive immune system, reacting to usually harmless things. The substances that cause allergic reactions are known as allergens. Your body thinks the allergen is an invader and makes antibodies to attack it. People who have allergies have an antibody called Immunoglobulin E, or IgE. When allergens first contact the body of a person with allergies, allergen-specific IgE antibodies are produced. Each type of IgE has specific “radar” for one type of allergen only. Thats why some people are allergic to cats only (they have only the IgE antibodies specific to cat) and others seem to be allergic to everything. When a person with allergies comes in contact with an allergen, his or her body will show symptoms of an allergic reaction, such as swelling of tissues, sneezing, wheezing, coughing, a runny nose, itchy eyes, and other reactions.
