A sty is a red, painful lump near the edge of your eyelid that may look like a boil or a pimple. Sties are often filled with pus. A sty usually forms on the outside of your eyelid. But sometimes it can form on the inner part of your eyelid.
In most cases, a sty will begin to disappear on its own in a couple days. In the meantime, you may be able to relieve the pain or discomfort of a sty by applying a warm washcloth to your eyelid.
A sty is a bacterial infection involving one or more of the small glands near the base of your eyelashes. It is similar to a boil or a pimple and is often painful.
Signs and symptoms of a sty include:
Another condition that causes inflammation of the eyelid is a chalazion. A chalazion occurs when there's a blockage in one of the small oil glands at the margin of the eyelid, just behind the eyelashes. Unlike a sty, a chalazion usually isn't painful and tends to be most prominent on the inner side of the eyelid. Treatment for both conditions is similar.
Most sties are harmless to your eye and won't affect your ability to see clearly. Try self-care measures first, such as applying a warm washcloth to your closed eyelid for 5 to 10 minutes several times a day and gently massaging the eyelid. Contact your doctor if:
A sty is caused by an infection of oil glands in the eyelid. The bacterium staphylococcus is responsible for most of these infections.
You are at increased risk of a sty if you:
To prevent eye infections:
Your doctor will usually diagnose a sty just by looking at your eyelid. Your doctor may use a light and a magnifying device to examine your eyelid.
In most cases, a sty doesn't require specific treatment. A sty typically goes away on its own. Recurrences are common.
For a sty that persists, your doctor may recommend treatments, such as:
Until your sty goes away on its own, try to:
Start by seeing your family doctor or a general practitioner if your sty is painful or doesn't start to get better in two days. In some cases, your doctor may refer you to a specialist who treats eye diseases and conditions (ophthalmologist).
Because appointments can be brief, it's a good idea to be prepared for your appointment. Here's some information to help you get ready.
Your time with your doctor is limited, so preparing a list of questions can help you make the most of your time together. For a sty, some basic questions to ask your doctor include: