What causes a stye and the best ways to get rid of one

• Styes are caused by infected oil glands on your eyelids, which form a red bump that resembles acne.
• Poor hygiene, old makeup, and certain medical or skin conditions can increase your risk for styes.
• To get rid of a stye, you can gently wash your eyelids, use a warm compress, and try antibiotic ointments.
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A stye is a red bump that forms on the eyelid and can look and feel like a big pimple. This bump often feels swollen and painful to the touch. Styes are basically like acne that occurs on the eyelid, says Amy Lin, MD, an ophthalmologist at the University of Utah Health.

Though styes can happen to anyone, there are certain behaviors that increase your risk. Here's what you need to know about the main causes of styes, how to prevent them, and what to do if you have one.

What causes a stye

Styes are caused by infected oil glands in your eyelids. These oil glands prevent tears from evaporating too quickly and drying out your eyes, but these glands can also become infected with bacteria.

There's one particular bacterium that leads to stye infections: Staphylococcus aureus. According to Tina Singh, MD, an ophthalmologist at Duke Eye Center, it's one of the most common bacteria on the skin, eyelids, and eyelashes, and can clog the oil glands.

While the bacterium is found in 20 to 30% of human nasal cavities without harm, you can also pick it up by touching surfaces infected with it, and S. aureus can become a pathogen itself when it gets under the skin, causing skin infections.

There a few reasons why people tend to get styes:

• Poor hygiene. Rubbing your eyes when you haven't washed your hands can lead to styes. "We carry a lot of bacteria on our hands, and that's easily transmissible to our eyelids and eyelashes," Singh says. Improper contact lens hygiene can also lead to styes, as it puts bacteria closer to the eyelids, so it's important to disinfect contact daily. "We don't recommend sleeping with contacts as well because bacteria love moist, dark environments," she says.
• Chlorine or sweat. "People should rinse their eyelids after getting out of a pool," Singh says, in addition to hot tubs, as there are chlorine-resistant bacteria that can cause eye infections. If you sweat from exercise or other activities, she says you should wash your eyelids after, as sweat and oil can clog the eyelid's oil glands and lead to infection.
• Makeup. "Lash extensions really attract a lot of dirt and bacteria, which can clog the [oil] glands," says Singh. "And makeup is the same way. Makeup really attracts a lot of dirt and bacteria," which can lead to oil gland infections on the eyelid and cause styes. The Cleveland Clinic recommends replacing eye makeup every six months to avoid an overgrowth of stye-causing bacteria.
• Skin conditions. "Some people with acne have a condition called rosacea, which can actually affect the eyes and can make them prone to have more styes," Lin says. Rosacea affects about 13 million Americans, and it involves broken blood vessels under the skin which can produce small, pus-filled bumps. The condition can occur on the eyes as well, called ocular rosacea, which can lead to blocked oil glands around the eyes. Seborrheic dermatitis can also increase your risk of styes, which is a chronic inflammatory skin condition that can lead to eyelid swelling and oily secretions.
• Medical conditions. Both Lin and Singh say that blepharitis can increase the risk of developing styes. Blepharitis causes eyelid inflammation and can often lead to excessive tearing, light sensitivity, redness of the eye, and a feeling like there's something in your eye. The condition also makes your eyelids prone to infection, which can lead to styes. High blood sugar can also cause a production of molecules that suppress immune defenses, so those with uncontrolled diabetes are more prone to infections, and may have a higher risk for styes.

How to get rid of a stye

"Some people have a tendency to get styes," Lin says, which could be due in part to the aforementioned poor hygiene, makeup, or medical conditions. "So if you've had styes in the past, you are more prone to get styes in the future. It doesn't really confer any resistance."

If styes keep recurring, you might consider treating it with antibiotic ointment, eye drops, pills, or even a steroid injection, according to the Cleveland Clinic.

To prevent getting styes in the first place, it's imperative to practice proper lid hygiene. Washing your whole face isn't enough, Singh says, and so you instead have to target your eyelids to get rid of styes.

Singh recommends washing your eyelids with baby shampoo (it's designed to be less harmful on your eyes) and warm water to clean along lash margin where styes tend to form.

If you've still developed a stye, though, there are ophthalmologist-recommended ways to safely get rid of them.

"Really, the best way is lots of warm compresses over the eyelids," says Lin. "Adding heat can get the oil glands to unclog and get them to release their oils naturally."

To do a warm compress, according to the American Academy of Ophthalmology, you should:

• Take a clean washcloth and soak it in hot water. Wring it out so that it's not dripping.
• Hold it to your eyelid for 10 to 15 minutes. If the cloth gets cold, warm it up again by dipping it in warm water.
• Do this three to five times a day.

"It's not recommended to try and squeeze [a stye]," Lin says. "Because that could actually cause us to get more inflamed and actually get worse." Instead, she says to let a stye run its course of about two to three weeks, using warm compresses to expedite the healing process.

While styes will typically clear up on their own, Singh notes that you should see a doctor if your stye causes vision problems. While a stye won't affect your eyeball, it can become so swollen it droops down into your eyesight.

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