Pink Eye (also called conjunctivitis) is redness and swelling of the conjunctiva, the mucous membrane that lines the eyelid and eye surface. The lining of the eye is usually clear. If irritation or infection occurs, the lining becomes red and swollen.
Pink Eye is very common. It usually is not serious and goes away in 7 to 10 days without medical treatment.
Most cases of Pink Eye are caused by infections caused by viruses or bacteria, dry eyes from lack of tears or exposure to wind and sun, chemicals, fumes, or smoke, or allergies.