Sty (Stye)

Medical Author:
Medical Editor:

What is a Sty (Stye)?

A sty is a bump that forms on or in the eyelid as the result of a blocked gland. The word "sty" can also be spelled "stye." There are two distinct types of stys: 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. Sebaceous glands secrete sebum, a waxy, oily material.

A chalazion is a blockage of a meibomian gland, which is a special sebaceous gland unique to the eyelids. These glands form a single row in each lid, with the body of the gland located inside the eyelid, and the opening located at the rim of the lid, posterior to the lashes. They secrete an oily material onto the surface of the eye, preventing the water layer of tears from evaporating too rapidly from the eye's surface between blinks. Therefore, poorly functioning meibomian glands can lead to dry eye symptoms.

What causes a Sty (Stye)?

Styes occur when a gland in or on the eyelid becomes plugged or blocked. This can occur if the gland's opening is obstructed by scar tissue or a foreign substance (makeup, dust), or if there is thickening of the substance produced by the gland, causing the material to flow sluggishly or not at all.

What are the risk factors for a Sty (Stye)?

Obstruction of the gland's opening can result from scar tissue following infections, burns, or trauma. Foreign substances such as makeup and dust can also clog the gland's opening if not properly washed away.

Sluggish outflow of the sebum from the meibomian glands is commonly seen in a chronic inflammatory condition called meibomian gland dysfunction (also commonly called meibomitis). Meibomian gland dysfunction is frequently associated with acne rosacea on the cheeks and nose, but can also be seen alone.

Medically Reviewed by a Doctor on 11/20/2013

Patient Comments

Viewers share their comments

Sty - Home Remedy Question: Did you try a home remedy that helped treat your sty?
Sty - Treatment Question: Did you try a treatment for sty that helped?
Sty - Prevention Question: Do you do anything special to prevent a sty?
Sty - Diagnosis Question: Were you ever diagnosed with a sty?
Sty (Stye) - Describe Your Experience Question: Please describe your experience with sty (stye).
Sty (Stye) - Causes Question: What were the causes of your sty?
Sty (Stye) - Symptoms Question: What symptoms did you have when you were suffering from a sty?

Sty Picture

A sty (sometimes spelled stye) is a tender, painful red bump located at the base of an eyelash or inside the eyelid. A sty results from an acute infection of the oil glands of the eyelid that occurs after these glands have become clogged.

Picture of a sty