Pink eye also is called conjunctivitis, which is an inflammation of the conjunctiva, the tissue covering the eye and inner surface of the eyelid. It can be infectious or noninfectious. The common types of noninfectious conjunctivitis are allergic conjunctivitis (caused by an allergic reaction) and irritant conjunctivitis (caused by anything that irritates the eyes, such as air pollution or chlorine in pools).In most cases, infectious conjunctivitis causes only minor problems with no risk of damage to the eyes or vision. In very rare instances, though, it can cause permanent damage or even blindness, so be sure to see your doctor if you think you have pinkeye.