Allergic Conditions
Allergies and allergic reactions occur when the immune system misidentifies harmless foreign substances-called allergens-and reacts to them as if they were harmful. Learn about common allergens such as food and insect stings.
These allergens can cause different kinds of allergic and related conditions that affect different parts of the body. In this section, learn about the most common allergic conditions and what types of allergens usually cause them.
Types
Allergic conditions include:
This information has been approved by David Tinkelman, MD (February 2006).
