Allergy : What are Allergies?

Allergies are unusual responses made by the immune system, the system that defends the body from disease. These responses are to things that are usually safe to most people. When you're allergic to something, your immune system thinks that it is harmful to your body, when it’s really not. Some things that cause allergic reactions include: certain foods, dust, plant pollen, and medicines, etc. These are known as allergens.

How do Allergies Happen? >