You get a stye when bacteria, almost always Staphylococcus aureus (staph), infect an oil gland or hair follicle along your eyelid. The result is a red, painful bump that looks a bit like a pimple and typically resolves on its own within one to two weeks. Styes are extremely common, and understanding exactly how they form can help you avoid getting them repeatedly.
What Causes a Stye to Form
Your eyelids contain dozens of tiny oil glands that help lubricate the surface of your eye. When one of these glands becomes blocked, oil builds up behind the obstruction. Staph bacteria, which naturally live on your skin and around your eyes, can then colonize that trapped oil and trigger an infection. The gland swells, fills with pus, and pushes outward to create the characteristic tender bump.
The blockage itself can happen for simple reasons: dead skin cells, dried oil, or debris clogging the gland opening. Touching your eyes with unwashed hands is one of the most direct ways to introduce extra bacteria. Sleeping in old eye makeup, using expired cosmetics, or sharing makeup tools can also push bacteria into those gland openings.
External vs. Internal Styes
Not all styes form in the same spot. An external stye, the more common type, develops at the base of an eyelash where it infects a hair follicle or one of the small oil glands right at the lid margin. These usually appear as a visible yellowish pustule surrounded by redness and swelling. Within two to four days, an external stye typically ruptures on its own, drains pus, and the pain subsides quickly after that.
An internal stye forms deeper in the eyelid, inside a larger oil gland called the meibomian gland. You’ll feel it more than you see it. The pain and swelling tend to be more intense, and internal styes rarely rupture on their own. When they do drain, it’s usually toward the inner surface of the eyelid rather than outward. Internal styes can also cause fever or chills in some cases because of the deeper infection.
Risk Factors That Make Styes More Likely
Some people get styes once and never again. Others deal with them repeatedly. The difference often comes down to a few key factors.
Blepharitis, a chronic inflammation of the eyelid margins, is one of the strongest risk factors. When the edges of your eyelids are constantly irritated and flaky, the oil glands are more prone to blockage, which sets the stage for bacterial infection. If you get styes frequently, underlying blepharitis is worth investigating.
Stress and sleep deprivation don’t directly cause styes, but they create conditions where styes are more likely to develop. Poor sleep lowers your body’s ability to fight off infections by reducing the effectiveness of immune cells called T cells. Stress hormones may also produce byproducts that help attract bacteria to vulnerable areas. On a more practical level, when you’re exhausted, you’re less likely to remove makeup before bed or wash your hands before rubbing your eyes.
Other common risk factors include wearing contact lenses without proper hygiene, reusing old or contaminated eye makeup, and having oily skin that makes gland blockages more frequent.
What a Stye Feels Like Day by Day
A stye usually begins with a vague tenderness or slight itch at the edge of your eyelid. Within about a day, a small, firm bump appears. The surrounding area turns red and swollen, and you may notice your eye watering more than usual or feeling like something is stuck in it. Some people also become sensitive to light.
Over the next few days, the bump develops a visible white or yellow head as pus collects inside. For external styes, the bump then pops and drains on its own, which brings quick relief. The whole process from first twinge to resolution takes about one to two weeks without treatment. With consistent warm compresses, many styes resolve faster.
How to Treat a Stye at Home
The single most effective home treatment is a warm compress. Soak a clean washcloth in warm water, wring it out, and hold it over your closed eye for five to ten minutes. Re-wet the cloth when it cools. After the compress, gently massage the eyelid to help the blocked gland open and drain. Repeat this two to three times a day.
Keep the area clean by gently washing the affected eyelid with mild soap and water. Skip eye makeup entirely until the stye heals, since cosmetics can reintroduce bacteria or irritate the area further. One critical rule: don’t squeeze or try to pop a stye. Unlike a regular pimple, squeezing can spread the infection deeper into the eyelid or into surrounding tissue.
Stye vs. Chalazion
A stye and a chalazion can look similar, but they behave differently. A stye is an active bacterial infection. It’s painful, red, swollen, and tender to touch. A chalazion is not an infection at all. It forms when a blocked oil gland triggers an inflammatory reaction without bacteria being involved. Chalazia are firm, round lumps that are not tender when you press on them.
Sometimes an untreated stye turns into a chalazion. Once the infection clears but the gland remains blocked, the leftover material hardens into a painless nodule. Chalazia can linger for weeks or months and occasionally need to be drained by a doctor if they don’t resolve on their own.
Preventing Styes From Coming Back
Good eyelid hygiene is the most reliable prevention strategy. Wash your hands before touching your face or handling contact lenses. Remove all eye makeup before bed every night, and replace mascara and eyeliner every few months since bacteria accumulate in the tubes. If you wear contacts, follow your cleaning schedule carefully and never sleep in lenses that aren’t designed for overnight wear.
If you’re prone to recurrent styes, a daily eyelid-cleaning routine can make a real difference. Gently scrubbing the lid margins with diluted baby shampoo or a commercial lid scrub removes the buildup of oil and dead skin that leads to gland blockages. A brief warm compress each morning can also keep the oil glands flowing freely before they have a chance to clog.