Pink eye is redness and swelling of the eye surface and the conjunctiva (the lining of the eyelid and the covering of the white part of the eye). Pink eye is also called conjunctivitis. Pink eye is often caused by infection with bacteria or a virus. Dry air, allergies, smoke, and chemicals are other common causes.
Pink eye often gets better on its own in 7 to 10 days. Antibiotics only help if the pink eye is caused by bacteria. Pink eye caused by infection spreads easily. If an allergy or chemical is causing pink eye, it will not go away unless you can avoid whatever is causing it.