A sty - a small abscess of the glands in the eyelids which can occur externally and internally. It's usually filled with pus. As it swells in size, the sty may make it difficult for you to see clearly because you can't fully open your eye.
More than one sty can occur at a time, leading to an inflammation at the margin or edge of your eyelid — a condition known as blepharitis. Fortunately, most sties disappear in just a few days. In the meantime, you can sometimes relieve the pain or discomfort of a sty with simple self-care treatments.
Signs and symptoms
Eventually most sties fill with pus and then rupture. The release of pus relieves one major symptom of sties — pain. Usually the sty then disappears. But before this happens, a sty typically exhibits the following signs and symptoms:
The cause of a sty is a bacterial infection. Usually the bacterial infection develops near the root (follicle) of an eyelash. You may have more than one sty at a time or several in succession.
Sties aren't very contagious. To minimize any risk of spreading this infection, however, encourage children to keep their hands away from their eyes and practice good hand washing techniques.
When to seek medical advice
Most sties are harmless to your eye and don't affect your ability to see clearly. Still, you may want to see your doctor if a sty causes one of the following problems:
Screening and diagnosis
If the symptoms of a sty persist or if you've had successive infections, your doctor may want to exclude other possible causes. Some conditions exist that are similar to a sty, but require different treatment. For instance a chalazion — a blockage in one of the small glands in the eyelid — can produce a swelling similar to that of a sty.
If your doctor confirms you have a sty, he or she can prescribe treatment or recommend ways to relieve your pain or discomfort. If a sty is ruled out, your doctor may refer you to an ophthalmologist for further examination and treatment. An ophthalmologist is a medical doctor who can provide comprehensive eye and vision care.
If your doctor confirms that you have a sty, he or she may prescribe a topical antibiotic cream to apply to your eyelid. To treat a pus-filled sty that won't rupture or burst on its own, your doctor or ophthalmologist may choose to lance and drain the lump to relieve pain and pressure. If you have multiple or recurrent sties, your doctor may also prescribe antibiotics.
Don't squeeze a sty or try to remove the pus prematurely. To relieve the pain and help a sty come to a point sooner, soak a clean cloth in warm water, wring it out and then apply it as a compress to your eyelid for 10 minutes, four times a day. Once the sty bursts on its own, keep the area clean and dry. To prevent recurrent infections, keep your hands away from your eyes and practice good hand washing techniques.