A bump resembling a pimple or small boil on the eyelid is likely a stye. Such lesions arise when an oil gland on the edge of the lid -- they can be toward the inside or the outside of the lid -- becomes inflamed. Swelling, tenderness, pain and redness are the hallmarks of styes. Swelling can affect a small area around the lesion or the whole eyelid. Another name for a stye is a hordeolum.
Doctors generally don't need to run special tests to diagnose a stye; they can tell what it is by looking. Apart from its characteristic appearance, a stye can cause a scratchy feeling as if you have something in your eye, according to MedlinePlus. It can also induce watering and hypersensitivity to light.
Styes occur when staphylococcal bacteria enter oil glands in the eyelids. Staphylococcal is common on the skin of humans, especially in the nose area. Rubbing your nose, then your eye, can easily transfer it. This bacterium is found in the nose and is transferred easily to the eye when you rub first your nose, then your eye. People who have blepharitis, a chronic inflammation of the eyelids, have an increased likelihood of developing styes, according to MedlinePlus.
You might not have to do anything to get rid of a stye. It tends to fade on its own in less than a week, according to All About Vision, a website run by Access Media Group and dedicated to eye care topics. One way to encourage healing is by applying hot compresses three to four times each day, 10 to 15 minutes each time. The approach encourages the lesion to form a head and rupture on its own, and in the meantime it helps relieve pain. If a stye is stubborn, an eye doctor can drain it. If you have recurrent styes, your physician might prescribe a topical antibiotic for prevention.
Don't squeeze or pop a stye; this can cause infection. In rare cases, infection and swelling can become severe enough to require urgent medical attention, according to the American Optometric Association. To avoid causing others to develop a stye or other problems, wash your hands frequently and thoroughly when you have a stye, and keep your eyes clean as well. Avoid sharing towels.
Not every bump in the eye area is a stye. A chelazion starts out looking like a stye but eventually develops into a painless, hard bump that can persist for a month or more, according to All About Vision. Another type of bump, the cyst, is a small sac full of fluid that can also form on the eyelid and affect the vision, according to MedlinePlus. Papillomas, which are slow-growing, wart-like bumps, can cause similar effects. Xanthelasma is a series of raised yellow areas on the eyelids. They tend to occur with age and are not harmful.