What Causes a Stye on the Eyelid?
You wake up with a sore spot near your eyelashes. By lunchtime, it looks like a small red pimple. It may sting when you blink and make your whole eyelid feel tender.
That painful bump could be a stye. Styes are common, uncomfortable, and usually short-lived. Still, they can be alarming when they appear without warning.
So, what causes a stye on the eyelid? Most styes begin when a tiny eyelid gland becomes blocked and infected by bacteria. Several everyday habits and health conditions can make that more likely.
This guide explains why styes form, what they look like, and how they differ from other eyelid bumps. It also covers safe care and signs that mean you should contact an eye doctor.
A stye, also called a hordeolum, is a painful eyelid bump caused by an infected oil gland or eyelash follicle.
This article is for general education. It cannot diagnose an eyelid bump or replace care from an optometrist, ophthalmologist, or other qualified clinician.
What Is a Stye on the Eyelid?
A stye is a small, inflamed bump on or inside the eyelid. It often appears red, swollen, and tender. Some styes develop a yellow or white point that looks like a pimple.
Your eyelids contain small glands that make oil. This oil helps keep your tears from drying too quickly. Your eyelashes also grow from tiny follicles in the eyelid skin.
When one of these openings becomes clogged, bacteria can become trapped. The gland or follicle may then become infected and swollen.
The medical name for a stye is hordeolum. You may hear an eye doctor use this term during an examination.
According to the American Academy of Ophthalmology, most styes are caused by a bacterial infection in a clogged eyelid gland.
What Causes a Stye on the Eyelid?
The direct cause is usually a bacterial infection. A common group of skin bacteria called Staphylococcus is often involved.
These bacteria normally live on the skin and inside the nose. Their presence does not mean a person is unclean. A problem can begin when bacteria enter a blocked gland or eyelash follicle.
The basic process often happens in three steps:
- Oil, dead skin, or other material blocks a gland opening.
- Bacteria enter or become trapped inside the blocked area.
- The body’s immune response causes pain, redness, and swelling.
The Mayo Clinic’s overview of stye causes also identifies infection of an eyelid oil gland as the main cause.
Blocked Eyelid Oil Glands
Eyelid glands release oil through very small openings. Thick oil, skin flakes, makeup, and inflammation can interfere with normal drainage.
A blocked gland does not always become infected. It may form a different bump called a chalazion. However, when bacteria infect the blocked area, a stye can form.
Bacteria in an Eyelash Follicle
An external stye often begins in the follicle where an eyelash grows. It may also affect a nearby gland.
Bacteria can reach the follicle through normal skin contact. Touching or rubbing the eyes with unwashed hands can increase that chance.
Eyelid Inflammation
Long-term eyelid inflammation can make gland openings easier to block. One common condition is blepharitis.
Blepharitis can cause crusting, burning, redness, and flakes around the eyelashes. The National Eye Institute’s guide to blepharitis explains that blocked eyelid glands can lead to styes.
Common Stye Risk Factors
A risk factor is not the same as a direct cause. It is something that increases the chance of a problem.
Anyone can develop an eyelid stye. However, the following factors may make one more likely.
Touching or Rubbing Your Eyes
Hands collect bacteria from phones, keyboards, handles, and many other surfaces. Touching the eyelids can move those bacteria near gland openings.
Rubbing can also irritate the eyelid and push debris toward the lash line. Wash your hands before touching your eyes whenever possible.
Sleeping in Eye Makeup
Mascara, eyeliner, and shadow can mix with oil and dead skin. Leaving them on overnight may block tiny eyelid glands.
Old or shared eye makeup may also carry bacteria. The FDA’s eye cosmetic safety guidance advises people not to share cosmetics. It also recommends discarding products used during an eye infection.
Remove makeup gently before bed. Clean applicators as directed and replace products according to their labels.
Poor Contact Lens Hygiene
Contact lenses do not directly cause every stye. However, handling lenses with unwashed hands can move bacteria to the eyelids and eyes.
The CDC’s contact lens safety guidance recommends washing and drying your hands before handling lenses. It also advises cleaning and storing reusable lenses correctly.
For more daily lens-care steps, see our guide to proper contact lens hygiene.
Blepharitis
Blepharitis is ongoing inflammation along the eyelid edge. It may cause flakes, crusts, itching, burning, or greasy-looking lashes.
The condition can disrupt the eyelid’s oil glands. People with blepharitis may therefore experience recurring styes.
Rosacea and Other Skin Conditions
Rosacea causes facial redness and inflammation. When it affects the eyes and eyelids, it may disturb the oil glands.
Acne, dandruff, and dry skin may also be linked with eyelid gland problems. A clinician can help identify and manage an underlying condition.
Diabetes and Other Health Factors
Some health conditions can affect the body’s response to infection. Diabetes is one condition associated with a higher risk of styes.
This does not mean every person with a stye has diabetes. A single stye is common and usually has a simple explanation. Frequent infections are worth discussing with a healthcare professional.
A History of Styes
People who have had a stye before may get another one. The original gland problem, eyelid inflammation, or daily habit may still be present.
Recurring styes deserve an eye examination. An optometrist or ophthalmologist can check for blepharitis, gland problems, or another type of eyelid growth.
External Stye vs. Internal Stye
Doctors group styes by where they form.
External Stye
An external stye develops near the outer eyelash line. It often begins in an eyelash follicle or nearby gland.
It may look like a small pimple. The bump is usually easy to see and may become tender quickly.
Internal Stye
An internal stye forms inside the eyelid. It affects a deeper oil-producing gland, often called a meibomian gland.
You may not see a clear bump from the outside. Instead, the eyelid may feel swollen and painful. Internal styes can sometimes cause more widespread tenderness.
Do not turn the eyelid inside out or press hard to inspect it. An eye doctor can examine the inner lid safely.
What Are the Symptoms of an Eyelid Stye?
Stye symptoms can vary based on the bump’s location and size. Common signs include:
- A painful bump near the eyelashes
- Local redness or discoloration
- Eyelid swelling
- Tenderness when blinking or touching the lid
- Watering or extra tears
- A scratchy feeling in the eye
- Crusting along the eyelid edge
- Sensitivity to light
- A small spot of pus
Not every eyelid bump is a stye. Our overview of common eye infections and their symptoms offers more background on problems that can cause redness or discomfort.
Stye vs. Chalazion: What Is the Difference?
A stye and a chalazion both involve blocked eyelid glands. However, they are not exactly the same.
| Feature | Stye | Chalazion |
|---|---|---|
| Usual cause | Blocked gland with bacterial infection | Blocked or inflamed gland without active infection |
| Pain | Often painful and tender | Usually painless after early tenderness fades |
| Location | Often near the eyelash edge | Often farther back in the eyelid |
| Appearance | Red bump that may contain pus | Firm, round lump under the skin |
| Usual course | Often improves within days to two weeks | May last several weeks |
A chalazion can sometimes develop after a stye. Because several conditions look similar, avoid diagnosing a bump from appearance alone.
Is a Stye Contagious?
A stye itself is generally not considered contagious. You cannot usually “catch” the bump from another person.
However, bacteria from the eyelid can spread through hands and personal items. Good hygiene still matters.
While a stye is active:
- Wash your hands before and after touching your eyelid.
- Do not share towels, washcloths, pillowcases, or eye makeup.
- Use a clean cloth for every warm compress.
- Avoid rubbing or squeezing the bump.
These steps may also reduce the risk of spreading bacteria to the other eye.
Can Stress or Lack of Sleep Cause a Stye?
Stress and poor sleep are often blamed for styes. However, neither is considered a proven direct cause.
Stress may change daily habits. A tired person may rub their eyes, skip makeup removal, or neglect lens care. These behaviors can increase exposure to bacteria or block glands.
It is more accurate to say stress may play an indirect role. The main cause remains an infected eyelid gland or follicle.
How to Care for a Stye Safely
Most styes improve without a medical procedure. Gentle home care can support natural drainage and reduce discomfort.
Use a Warm Compress
Soak a clean washcloth in warm, not hot, water. Wring it out and place it over the closed eyelid.
The Mayo Clinic suggests using a warm washcloth for 5 to 10 minutes several times daily. Rewarm the cloth as needed. Use a fresh, clean cloth each time.
Warmth may soften thick oil and help the gland drain on its own. Stop if the compress feels too hot or causes more pain.
Keep the Eyelid Clean
Clean hands and gentle eyelid care can limit further irritation. Avoid harsh soaps, alcohol, essential oils, and homemade mixtures near the eye.
If you have ongoing eyelid crusting, ask an eye doctor about an eyelid-cleaning routine. Products and methods are not suitable for every eye condition.
Pause Makeup and Contact Lenses
Eye makeup can further block the gland or introduce more bacteria. Contact lenses may also irritate an already sore eyelid.
Consider using glasses while the area heals. Ask your eye care provider when it is safe to restart contacts. Do not reuse products that may have become contaminated.
Do Not Pop or Squeeze a Stye
A stye may look like a pimple, but it should not be treated like one. Squeezing can injure delicate eyelid tissue or spread infection.
Let the bump drain naturally. An eye doctor can drain a stubborn stye using sterile instruments when needed.
Avoid Leftover Medicines
Do not use old antibiotic drops, someone else’s prescription, or skin acne cream on the eyelid. The wrong product can irritate the eye or delay proper treatment.
An eye doctor may prescribe antibiotic ointment, drops, or another treatment in selected cases. These medicines are not needed for every stye.
When Should You See an Eye Doctor for a Stye?
Contact an optometrist, ophthalmologist, or other healthcare professional if the stye does not start improving after about 48 hours. You should also seek care if it keeps returning.
Get prompt medical help if:
- Your vision becomes blurry or changes
- The eye swells shut
- Redness or swelling spreads across the eyelid, cheek, or face
- Pain or swelling becomes worse after two or three days
- The eyelid feels hot or leaks blood or a large amount of pus
- You have fever, feel very unwell, or have pain when moving the eye
- The bump returns in the same place
These signs may point to a deeper infection or another condition. An eye professional can examine the eyelid and decide whether treatment is needed.
Read our guide to signs you need to visit an eye doctor for more symptoms that should not be ignored.
How to Help Prevent Future Styes
There is no guaranteed way to prevent every stye. Still, a few habits can lower your risk:
- Wash your hands before touching your eyes or contact lenses.
- Avoid rubbing your eyelids.
- Remove eye makeup before sleeping.
- Replace old eye cosmetics and never share them.
- Clean makeup tools according to the maker’s instructions.
- Follow your eye doctor’s contact lens care plan.
- Keep reusable lens cases clean and replace them regularly.
- Follow treatment guidance for blepharitis or rosacea.
- Use only clean towels and washcloths near your face.
- Schedule an eye examination if styes keep returning.
These habits support overall eye health as well. For a broader routine, explore our tips for maintaining optimal eye health.
The Practical Takeaway
What causes a stye on the eyelid? In most cases, bacteria infect a blocked oil gland or eyelash follicle. Unwashed hands, old makeup, poor lens hygiene, and eyelid inflammation can increase the risk.
Most styes settle with time, gentle cleaning, and warm compresses. Do not squeeze the bump or apply unapproved products near your eye.
Pay attention to changes in vision, spreading redness, severe swelling, or worsening pain. If these occur, contact an optometrist or ophthalmologist promptly. It is always safer to have an unusual or recurring eyelid bump examined.
Frequently Asked Questions About Eyelid Styes
1. How long does a stye usually last?
Many styes begin improving within a few days and clear within one or two weeks. Healing time varies. Contact an eye professional if it worsens or does not start improving after about 48 hours.
2. Can a stye form inside the eyelid?
Yes. An internal stye forms in an oil gland on the inner eyelid. It may cause deeper pain and swelling without an obvious outer bump.
3. Can old mascara cause a stye?
Old mascara may carry bacteria or contribute to blocked gland openings. It is a risk factor, not a guaranteed cause. Follow the product’s replacement guidance and do not share eye makeup.
4. Should I wear contact lenses with a stye?
It is often best to use glasses while the eyelid is sore or infected. Contacts can add irritation and may become contaminated. Ask your eye care provider when to restart lens wear.
5. Is a stye the same as pink eye?
No. A stye is a localized, painful eyelid bump. Pink eye affects the thin tissue over the white of the eye and inner eyelid. It often causes widespread redness, discharge, or itching.
6. Why do I keep getting styes?
Recurring styes may relate to blepharitis, rosacea, eyelid gland problems, makeup habits, or lens hygiene. An optometrist or ophthalmologist can look for an underlying cause.
7. Can I pop a stye when it develops a white head?
No. Popping or squeezing a stye can spread infection and damage the eyelid. Use warm compresses and let it drain naturally. A clinician can drain it safely if needed.
