Overview
A sty (hordeolum) is a painful red lump on or inside the eyelid, caused by infection of an eyelid gland or hair follicle — usually by Staphylococcus aureus bacteria. External sties form along the lash line; internal sties are deeper in the eyelid. Most sties resolve on their own within 1 to 2 weeks. A chalazion is a non-infectious blocked meibomian gland that may look similar.
How common is it?
Sties are very common, affecting most people at least once. They are more common in people who touch their eyes frequently, have poor hygiene habits, use contact lenses, or have blepharitis.
Causes and risk factors
Bacterial infection, usually Staphylococcus aureus, blocks and infects the glands in the eyelid.
Common risk factors
- Touching or rubbing eyes with unwashed hands
- Sharing eye cosmetics or contact lens equipment
- Blepharitis (chronic eyelid inflammation)
- Skin conditions: acne rosacea, seborrhoeic dermatitis
- Contact lens use
- Previous sty (risk of recurrence)
Symptoms
- Painful red swelling on the edge of the eyelid
- Visible yellow pus-filled centre as it develops
- Swelling and redness of the surrounding eyelid
- Watering eye
- Discomfort when blinking
- Feeling of a foreign body in the eye
When to see a doctor
See a doctor if the sty has not resolved within 2 weeks, is growing rapidly, vision is affected, the swelling spreads beyond the eyelid to the cheek or orbital area, or if there is fever. Preseptal or orbital cellulitis is a serious complication requiring urgent treatment.
Diagnosis
Clinical diagnosis by examination. No investigations required in uncomplicated cases.
Treatments
Warm compresses
The primary treatment. Apply a warm, clean cloth to the closed eyelid for 10 to 15 minutes, 3 to 4 times daily. Heat promotes blood flow and softens the blocked gland, encouraging spontaneous drainage. This resolves most sties within 1 to 2 weeks.
Antibiotic ointment or drops
Topical chloramphenicol or fusidic acid ointment applied to the eyelid can speed resolution and prevent spread. Oral antibiotics only for spreading cellulitis or immunocompromised patients.
Incision and drainage
For sties that do not resolve after 2 to 3 weeks or are particularly large and painful, incision and drainage under local anaesthetic provides rapid relief.
Self-care and lifestyle
- Never squeeze or pop a sty — this can spread the infection
- Remove eye make-up completely each evening and replace eye cosmetics every 3 to 6 months
- Do not wear contact lenses until the sty has healed
- Do not share towels, washcloths, or eye cosmetics
Prevention
Wash hands before touching the eye area. Remove all eye make-up before sleeping. Treat blepharitis promptly with lid hygiene measures. Do not share eye cosmetics.