Eye allergies, also called allergic conjunctivitis, is a common condition that occurs when the eyes react to something that irritates them. The eyes produce a substance called histamine to fight off the allergen. As a result, the eyelids and conjunctiva become red, swollen and itchy, with tearing and burning. Unlike bacterial or viral conjunctivitis, allergic conjunctivitis is not spread from person to person. Read more about the symptoms here.