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Symptoms and Signs of Sty (Stye)

Doctor's Notes on Sty (Stye)

sty (or stye) is a localized infection causing inflammation of the edge of the eyelid, typically involving the eyelash hair follicles or eyelid glands (Meibomian glands). The medical term for sty is hordeolum. Infection with the bacterium Staphylococcus aureus (S. aureus) is the most common cause of a sty.

A sty produces characteristic signs and symptoms. There is usually a bump or lump on the eyelid margin. The bump resembles a pimple or boil. Associated symptoms can include eyelid swelling, pain in the eyelids, redness of the overlying skin, swelling of the eyelid, and increased tear production. There may also be a sense of having a foreign body in the eye. A sty can be located on the exterior (facing outward) or interior surface of the eyelid.

Medical Author:
Medically Reviewed on 3/11/2019

Sty (Stye) Symptoms

Symptoms and signs of a stye include the following:

  • A lump on the top or bottom eyelid
  • Localized swelling of the eyelid
  • Pain
  • Redness
  • Tenderness to touch
  • Crusting of the eyelid margins
  • Burning in the eye
  • Droopiness of the eyelid
  • Scratchy sensation on the eyeball
  • Blurred vision
  • Mucous discharge in the eye

Sty (Stye) Causes

Infections of the oil glands in the eyelid cause styes. Very frequently, bacteria (most commonly Staphylococcus bacteria) infect the oil glands in the eyelids.

Seborrhea (excessive oily discharge from the glands) may increase the likelihood of developing one of these infections. Certain other factors can contribute to the infection of the glands:

Common Eye Problems and Infections Slideshow

Common Eye Problems and Infections Slideshow

When it comes to signs of eye disease, Americans are blind to the facts. A recent survey showed that while nearly half (47%) of Americans worry more about going blind than losing their memory or their ability to walk or hear, almost 30% of those surveyed admitted to not getting their eyes checked.

The following slides take a look at some of the signs and symptoms of some of the most common eye diseases.


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.