Allergic conjunctivitis causes red, watery, itchy eyes. It is caused by exposure to irritants such as plant pollens, pet fur, cosmetics or house dust mite. Seasonal allergic conjunctivitis occurs at certain times in a year, a common cause being an allergy to pollen in the hay fever season. Perennial allergic conjunctivitis persists throughout the year. This is commonly due to an allergy to house dust mite or animal hair.
This is a companion discussion topic for the original article at https://patient.info/medicine/nedocromil-sodium-eye-drops