Medically reviewed on June 5, 2018
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:
- A red lump on your eyelid that is similar to a boil or a pimple
- Eyelid pain
- Eyelid swelling
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.
When to see a doctor
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:
- The sty doesn't start to improve after 48 hours
- Redness and swelling extend beyond your eyelid and involve your cheek or other parts of your face
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:
- Touch your eyes with unwashed hands
- Insert your contact lenses without thoroughly disinfecting them or washing your hands first
- Leave on eye makeup overnight
- Use old or expired cosmetics
- Have blepharitis, a chronic inflammation along the edge of the eyelid
- Have rosacea, a skin condition characterized by facial redness
To prevent eye infections:
- Wash your hands. Wash your hands with soap and warm water or use an alcohol-based hand sanitizer several times each day. Keep your hands away from your eyes.
- Take care with cosmetics. Reduce your risk of recurrent eye infections by throwing away old cosmetics. Don't share your cosmetics with others. Don't wear eye makeup overnight.
- Make sure your contact lenses are clean. If you wear contact lenses, wash your hands thoroughly before handling your contacts and follow your doctor's advice on disinfecting them.
- Apply warm compresses. If you've had a sty before, using a compress regularly may help prevent it from coming back.
- Manage blepharitis. If you have blepharitis, follow your doctor's instructions for caring for your eyes.
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:
- Antibiotics. Your doctor may prescribe antibiotic eyedrops or a topical antibiotic cream to apply to your eyelid. If your eyelid infection persists or spreads beyond your eyelid, your doctor may recommend antibiotics in tablet or pill form.
- Surgery to relieve pressure. If your sty doesn't clear up, your doctor may make a small cut in it to drain the pus. This helps speed healing and relieve the pain and swelling.
Lifestyle and home remedies
Until your sty goes away on its own, try to:
- Leave the sty alone. Don't try to pop the sty or squeeze the pus from a sty. Doing so can cause the infection to spread.
- Clean your eyelid. Gently wash the affected eyelid with mild soap and water.
- Place a warm washcloth over your closed eye. To relieve pain, run warm water over a clean washcloth. Wring out the washcloth and place it over your closed eye. Re-wet the washcloth when it loses heat. Continue this for 5 to 10 minutes. Then gently massage the eyelid. Repeating this two to three times a day may encourage the sty to drain on its own.
- Keep your eye clean. Don't wear eye makeup until the sty has healed.
- Go without contacts lenses. Contact lenses can be contaminated with bacteria associated with a sty. If you wear contacts, try to go without them until your sty goes away.
Preparing for an appointment
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.
What you can do
- List any symptoms you're experiencing, including those that seem unrelated to the sty.
- List key personal information you feel may be important for your doctor to know.
- Make a list of all medications, vitamins and supplements that you're taking.
- List questions to ask your doctor.
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:
- What is the likely cause of my sty?
- When can I expect my sty to go away?
- Is this contagious?
- What kinds of tests do I need?
- Are there any treatments for my sty?
- What are the benefits and risks of these treatments?
- What can I do to prevent future sties?
- Can I continue wearing contact lenses?
- Is there a generic alternative to the medicine you're prescribing me?
- Do you have any brochures or other printed material that I can take with me?
- What websites do you recommend?
- Do I need a follow-up visit?