what is pink eye

Pink eye, also known as conjunctivitis, is an inflammation of the transparent membrane that lines the eyelid and eyeball called the conjunctiva. When small blood vessels in the conjunctiva become swollen and irritated, they become more visible, causing the whites of the eyes to appear reddish or pink. Typical symptoms of pink eye include redness and a gritty sensation in the eye, along with itching and a discharge that forms a crust on the eyelashes during the night. Other symptoms can include increased tear production, feeling like a foreign body is in the eye, and crusting of eyelids or lashes, especially in the morning. Pink eye can be caused by a viral or bacterial infection, an allergic reaction, or an incompletely opened tear duct in babies. It can also be caused by irritants such as smoke, dust, or chemicals. While pink eye can be irritating, it rarely affects vision and treatments can help ease the discomfort.