allergies

An allergy is an immune response by the body to certain stimuli in the environment that are normally harmless.

 

The immune system is made up of chemical pathways and cells within the body. When these are activated, an allergic response occurs. Allergies occur in response to normally harmless triggers known as allergens. The body of a person with an allergy responds to an allergen by attacking it. The immune response activates certain immune cells called mast cells. Mast cells trigger the release of chemicals known as histamine and leukotrienes which, in turn, act on tissues in the body and create the allergic response.

 

Allergies can affect nearly any part of the body. The nose, sinuses, eyes, lungs, and skin are most often affected. Symptoms may include:

 

No one knows for sure why some people have allergies and others do not. Family history appears to play a part in a person's development of allergies.

There is little that can be done to prevent allergies from developing. Once they have developed, flare-ups can be reduced by allergy shots. These shots consist of tiny but gradually increasing doses of the substance to which the person is allergic. In response to the shots, the person's sensitivity to the allergen decreases.

Allergies are generally diagnosed with a medical history and physical examination. Blood tests and skin testing can be done to identify specific allergens.