Overview, Causes, & Risk Factors

A stye is a bacterial infection of one of the hair follicles of the eyelashes or one the small glands near the inner corner of the eye.

What is going on in the body?

A stye occurs when bacteria infect one of the hair follicles of the eyelashes or one of the glands near the inner corner of the eye. Ninety five percent of the time, the infection is caused by Staphylococcus aureus bacteria.

What are the causes and risks of the infection?

Ninety five percent of the time, a stye is caused by the bacteria Staphylococcus aureus. Other bacteria may be involved less often. Risk factors that increase a person's chance of developing a stye include the following:

Symptoms & Signs

What are the signs and symptoms of the infection?

A stye appears as a red, tender, raised area. It usually develops over a 24-hour period near the eyelashes or the inner corner of the eye. There may also be blurred vision and aching.

Sometimes a secondary infection of the eyelid, known as conjunctivitis, may occur. Conjunctivitis may cause eye itching, discharge, and redness.

Diagnosis & Tests

How is the infection diagnosed?

The healthcare provider can diagnose a stye with a medical history and physical examination.

Prevention & Expectations

What can be done to prevent the infection?

In some cases, styes cannot be prevented. The following measures can help minimize or prevent styes:

What are the long-term effects of the infection?

Repeated infections can lead to scarring of the eyelid. The eyelashes may also grow in an unnatural direction. If styes form repeatedly, a chalazion may develop. A chalazion is a noncancerous mass or cyst on one of the eyelids.

What are the risks to others?

Styles are not contagious and pose no risk to others.

Treatment & Monitoring

What are the treatments for the infection?

Styes usually respond well to hot compresses. If the compresses do not give relief within 24 hours, the healthcare provider should be consulted. Topical antibiotics, such as bacitracin or tobramycin, may be needed.

Sometimes the infection spreads to the eyelid or the lymph nodes in front of the ear. The healthcare provider may then prescribe oral antibiotics, such as dicloxacillin, cephalexin, erythromycin, or tetracycline.

Rarely, when a large stye does not respond to treatment, the healthcare provider may drain the infection through a small incision.

What are the side effects of the treatments?

Topical antibiotics may cause allergic reactions. The antibiotics used to treat a stye can cause a rash, light sensitivity, stomach upset, or allergic reactions. Draining the stye through an incision may cause bleeding, infection, or allergic reaction to anesthesia.

What happens after treatment for the infection?

A stye should clear up in two to three days. No further treatment is required.

How is the infection monitored?

Any new or worsening symptoms should be reported to the healthcare provider.