Acute conjunctivitis, or pink eye, is an inflammation or infection of the conjunctiva that causes the eyelids to swell and cover the eyeball. Although conjunctivitis can be uncomfortable, it rarely affects your vision.

Conjunctivitis, or pink eye, is an inflammation or infection of the conjunctiva that causes the eyelids to swell and cover the eyeball. When the tiny blood vessels in the conjunctiva become inflamed, they become more visible, causing the whites of your eyes to appear red or pink.