What Are Allergies?

What are allergies? Could my indoor air be the problem? What are allergies?

The term "allergies" refers to the body's usually unpleasant response when some particle or substance that it does not recognize comes in contact with tissue. This reaction is usually in response to a particle or substance coming in contact with the skin, ingested (eating/swallowing), or being inhaled and entering the airway. Essentially what happens is this: once an allergen (reaction causing substance) contacts skin or internal tissue, the body releases histamine, a nitrogen compound found in mast cells and white bloods cells, which are cells found in lots of tissue, especially hands, feet, mouth,internal tissue, and blood vessels. People with severe allergies tend to have more of these types of cells.