A stye, also known as a hordeolum, is a bacterial infection of an oil gland in the eyelid. This results in a red tender bump at the edge of the eyelid. The outside or the inside of the eyelid can be affected.The cause of a stye is usually a bacterial infection by Staphylococcus aureus. The internal ones are due to infection of the meibomian gland while the external ones are due to an infection of the gland of Zeis. A chalazion on the other hand is a blocked oil gland without infection. A chalazion is typically in the middle of the eyelid and not painful.Often a stye will go away without any specific treatment in a few days or weeks. Recommendations to speed improvement include warm compresses. Occasionally antibiotic eye ointment may be recommended. While these measures are often recommended, there is little evidence for use in internal styes. The frequency at which styes occur is unclear, though they may occur at any age. Signs and symptoms
The first sign of a stye is a small, yellowish spot at the center of the bump that develops as pus and expands in the area.Other stye symptoms may include:

A lump on the top or bottom eyelid
Localized swelling of the eyelid
Localized pain
Redness
Tenderness
Crusting of the eyelid margins
Burning in the eye
Droopiness of the eyelid
Scratchy sensation on the eyeball (itching)
Blurred vision
Mucous discharge in the eye
Irritation of the eye
Light sensitivity
Tearing
Discomfort during blinking
Sensation of a foreign body in the eye

Complications
Stye complications occur in very rare cases.
In Czech, a sty is called ječné zrno (from ječmen "barley" and zrno "seed or grain"); in German, it is called Gerstenkorn (barleycorn). In Hebrew it is called "שעורה" Seh-oh-Ráh (Barley)

See also
Boil

References
External links

Merck Manual
Willmann, D.; Guier, C. P.; Patel, B. C.; Melanson, S. W. (2021). "Stye". NIH - StatPearls - Stye. StatPearls. PMID 29083787.