Eye Allergy or Ocular Allergy occurs when something you are allergic to irritates the conjunctiva. This is the delicate membrane covering the eye and the inside of the eyelid.
Like all allergies, allergic conjunctivitis starts when the immune system identifies an otherwise harmless substance as an allergen. This causes your immune system to overreact and produce antibodies called Immunoglobulin (IgE). These antibodies travel to cells that release chemicals which cause an allergic reaction. In this case, allergic reactions include eyes that water, itch, hurt or become red or swollen.
The most common causes of allergic conjunctivitis are seasonal allergens such as pollen and mold spores. People with seasonal allergic rhinitis (hay fever) normally notice their symptoms worsen when they go outdoors on days with high pollen counts.
Indoor allergens such as dust mites and pet dander can also cause eye allergies year-round. If you suffer from this type of allergy, you may notice your symptoms worsen during certain activities such as cleaning your house or grooming a pet.
Eye allergy symptoms can be very annoying. Yet they pose little threat to eyesight other than temporary blurriness. Unlike conditions such as pink eye, allergic conjunctivitis is not contagious.
However, red, itchy, burning and puffy eyes can be caused also by infections and other conditions that can threaten eyesight.