A sty is a bacterial infection that often appears as a small bump along the edge of the eyelid. It usually appears among the eyelashes and may have an eyelash protruding from it.
Stys are usually painful, red and swollen.
They eventually fill with pus and form a yellow or white head. A sty does not usually require a trip to your doctor and can be cared for at home by applying warm compresses for ten to fifteen minutes, four times a day. This treatment should be continued for three or four days to relieve pain, swelling and promote drainage of the pus. A sty should never be squeezed or rubbed. Squeezing will make the swelling worse and rubbing may spread the infection.