Conjunctivitis is the most common eye disease in the western hemisphere. It is an inflammation of the conjunctiva which makes the sclera appear reddened due to an increase in blood supply. The eye feels itchy and watery. Sometimes, there is a sticky discharge, which feels uncomfortable and makes vision blurry. Although conjunctivitis is often referred to as 'pink eye', this technically only refers to one type of the eye disease, bacterial conjunctivitis.