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What is a sty in the eye?

March 18, 2015

If you have ever had a small, painful lump along the edge of your eyelid then you have probably had a sty (also spelled stye). While styes are fairly common and are usually visible on the outer eyelid, they have formed deeper inside the eyelid in some cases as well.  Let’s look at the causes, types and treatments of styes to keep you informed in case you suspect that you may be suffering from one of these painful blockages.

What is a sty and what causes it?

A sty is an external bump on the eyelid that swells and then eventually bursts then heals.  The sty originally forms due to a blocked gland that needs to become cleared.  There are two main types of sty lumps.  These include: hordeolum and chalazion. Each has different causes and treatments.


A hordeolum is a blockage of one of the sweat glands found in the skin of the lid and base of the eyelashes, or one of the small sebaceous glands found at the base of the eyelashes.


A chalazion is a blockage of a meibomian gland, which is a special sebaceous gland unique to the eyelids.

The sty can occur due to a gland becoming blocked with its own secretion or possibly from makeup, dust or other foreign substances.  It can also be caused by a sluggish gland that was infected or had some sort of trauma.

What are the treatments for a sty on the eyelid?

A non-infected hordeolum will resolve on its own. Warm compresses may help soften the material in the gland, easing the drainage of the gland’s contents. A non-infected chalazion similarly will resolve on its own, though over a much longer period of time. A small chalazion may resolve within weeks, while larger ones may resolve over the course of a year. The most conservative treatment is application of frequent warm compresses. Steroids can be injected into the lesion, often resulting in a speedier resolution. However this carries a small risk of bleeding/bruising, depigmentation/thinning of the skin, scar, pain, and in very rare cases, loss of vision. Finally, the chalazion can be incised and drained. This is the most invasive method and is reserved as a last resort by most eye doctors.