A stye is a painful, pus-filled bump on the eyelid caused by a bacterial infection in one of the small oil or sweat glands near your eyelashes. It looks like a red, swollen lump, often with a visible yellow center where pus has collected. Most styes resolve on their own within one to two weeks, starting as a tender swelling and ending when the abscess drains naturally.
External vs. Internal Styes
There are two types, and the difference comes down to which gland is infected. External styes form right at the edge of the eyelid, at the base of an eyelash. They involve the tiny oil glands or sweat glands that sit alongside each lash follicle. Because they’re on the surface, you can usually see the bump clearly.
Internal styes develop deeper inside the eyelid, in larger oil glands embedded in the firm tissue (called the tarsal plate) that gives your eyelid its shape. These glands produce the oily layer of your tear film. An internal stye may not be as visible from the outside, but it can cause more diffuse swelling and discomfort because the infection sits beneath the skin rather than on it.
Causes and Risk Factors
Staphylococcus bacteria are the usual culprit. These bacteria live on skin and are normally harmless, but when an oil gland along the eyelid becomes clogged, bacteria can multiply inside it and trigger an infection. The gland swells, fills with pus, and becomes painful to the touch.
Several things raise your risk. Blepharitis, a chronic low-grade inflammation along the eyelid margin, is one of the most common. If your eyelids frequently look red or crusty at the lash line, you’re more prone to blocked glands and repeat infections. Other risk factors include touching your eyes with unwashed hands, sleeping in contact lenses, and using old eye makeup. The FDA notes that industry experts recommend replacing mascara every three months because of repeated bacterial exposure during use.
What a Stye Feels Like
The first sign is usually tenderness or a gritty, irritated sensation in one spot on the eyelid. Within a day or so, a red, swollen bump appears. It’s painful, especially when you blink or press on it. Your eye may water more than usual, and the eyelid can feel heavy or puffy. As the stye matures, a small yellow or white head of pus often becomes visible at the center.
Some people also notice sensitivity to light or a feeling like something is in their eye, particularly with internal styes that press against the eyeball from inside the lid.
Styes vs. Chalazia
A chalazion can look similar to a stye but behaves differently. The key distinction is pain: styes hurt, while chalazia typically don’t, even when you press on them. Chalazia also lack the pus-filled center that styes develop. They tend to form farther from the lash line, on the inner part of the eyelid, and grow more slowly into a firm, round nodule.
A stye that doesn’t drain and doesn’t resolve can sometimes turn into a chalazion over time. If you have a painless lump on your eyelid that’s been there for several weeks, it’s likely a chalazion rather than an active infection.
Home Treatment
Warm compresses are the standard first-line treatment. Soak a clean washcloth in warm water, wring it out, and hold it gently against the affected eyelid for five to ten minutes. Repeat this several times a day until the stye drains. The heat helps loosen the clogged oil inside the gland and encourages the abscess to open on its own.
One important rule: never squeeze or pop a stye. The American Academy of Ophthalmology warns that doing so can release bacteria and spread the infection to other parts of the eye. Let it drain naturally. While you’re waiting, avoid wearing contact lenses and eye makeup on the affected eye.
Keep the eyelid clean by gently washing it with mild soap or a diluted baby shampoo solution. Avoid rubbing or touching the bump repeatedly, since your hands can introduce more bacteria.
When Treatment Goes Further
Most styes don’t need anything beyond warm compresses. If a stye hasn’t improved after a week or two of consistent home care, or if it’s getting larger rather than smaller, a doctor may prescribe antibiotic ointment or drops to help clear the infection. For particularly stubborn or large styes, a minor in-office procedure can drain the abscess through a small incision. This is quick, done under local numbing, and provides immediate relief from the pressure.
Possible Complications
Serious complications from styes are uncommon, but the infection can occasionally spread to the surrounding skin. This condition, called preseptal cellulitis, causes redness and swelling that extends beyond the bump itself, spreading across the eyelid or around the eye socket. The skin feels warm and tender to touch. Preseptal cellulitis needs prompt antibiotic treatment but is generally manageable when caught early.
Warning signs that need urgent attention include fever, eye pain, changes in vision, or the eye itself beginning to bulge forward. These suggest the infection may have spread to deeper tissues behind the eye, which is a more serious situation requiring emergency care.
Preventing Styes
Good eyelid hygiene is the most effective prevention. Wash your hands before touching your face or handling contact lenses. Remove all eye makeup before bed, and replace mascara and eyeliner every three months rather than using them until they run out. If you wear contact lenses, follow the recommended cleaning and replacement schedule closely.
If you have blepharitis or get styes repeatedly, a daily eyelid-cleaning routine can help keep the oil glands along your lash line from clogging. A warm compress for a few minutes each morning, followed by gentle cleaning of the lid margins, reduces the buildup that leads to blocked glands and infections.