What are allergies and what causes them?

You have an allergy when your body overreacts to things that don’t cause problems for most people. These things are called allergens. Sometimes the term “hay fever” or “rose fever” is used to describe an allergic reaction to allergens in the air. Your body’s overreaction to an allergen is what causes allergy symptoms (see the box to the right).

Common symptoms of allergies:

• Runny nose
• Watery eyes
• Itchy nose, eyes and roof of mouth
• Sneezing
• Stuffy nose
• Pressure in the nose and cheeks
• Ear fullness and popping
• Dark circles under the eyes
• Hives