Sub-tarsal foreign body (STFB)


Patient may give history of foreign body entering eye

  • particle falling into eye (rust while working under car, DIY debris)
  • wind blown from unknown source

Predisposing factors

Lack of suitable eye protection

Symptoms of sub-tarsal foreign body

Foreign body sensation / acute pain (worse on blinking)
Red eye

Signs of sub-tarsal foreign body

Possible fluorescein staining of cornea

  • foreign body tracks, often vertical

Embedded material on tarsal conjunctival surface

Differential diagnosis

Dendritic ulcer
Corneal abrasion (e.g. from contact lens) (see Clinical Management Guideline on Corneal Abrasion)
Superficial punctate keratopathy of another cause
NB: check cornea for adherent/embedded material

Management by optometrist

Practitioners should recognise their limitations and where necessary seek further advice or refer the patient elsewhere

GRADE* Level of evidence and strength of recommendation always relates to the statement(s) immediately above

Non pharmacological

Evert upper eyelid 

Remove foreign body, after instillation of topical anaesthetic, with:

  • saline irrigation
  • sterile saline-wetted cotton bud (can also be used to sweep the fornix)
  • sterile hypodermic needle if cannot be dislodged by cotton bud

(GRADE*: Level of evidence=low, Strength of recommendation=strong)

Advise patient to return/seek further help if symptoms persist
Advise on future suitable eye protection
(GRADE*: Level of evidence=low, Strength of recommendation=strong)


Local anaesthetic (e.g. g. oxybuprocaine 0.4%) to aid examination and removal of foreign body

(GRADE*: Level of evidence=low, Strength of recommendation=strong)

  • After removal, prescribe tear supplements / lubricants for symptomatic relief

(GRADE*: Level of evidence=low, Strength of recommendation=strong)

  • Consider prophylactic antibiotic (e.g. course of chloramphenicol drops/ointment for not less than 5 days) if there is substantial epithelial loss or foreign matter contamination of the conjunctival sac (see Clinical Management Guideline on Corneal Abrasion)

(GRADE*: Level of evidence=low, Strength of recommendation=weak)

Management category

B3: Management (including drugs) to resolution. Normally no referral.

Possible management by ophthalmologist

(Normally no referral)

Evidence base

*GRADE: Grading of Recommendations Assessment, Development and Evaluation (

Sources of evidence

Eye trauma. 2019 BMJ Best Practice


What is Sub-tarsal Foreign Body?

Sometimes a speck of dust or other debris, landing on the eye, becomes trapped under the upper eyelid. While there it may cause discomfort which increases on blinking when the foreign body is rubbed over the eye surface. Usually the patient will know that something has blown into the eye.

How is Sub-tarsal Foreign Body managed?

The optometrist will turn the upper eyelid over and, if a foreign body is found, remove it. Sometimes a drop of local anaesthetic is needed to reduce the discomfort of this procedure. Generally, no further treatment is needed, but if there is a large abrasion of the surface of the cornea (the clear window at the front of the eye) or any evidence of infection, a course of local antibiotic drops or ointment may be prescribed. Such cases are not usually referred to the ophthalmologist.

Sub-tarsal foreign body (STFB)
Version 12
Date of search 17.11.21 
Date of revision 09.05.22
Date of publication 14.09.22
Date for review 16.11.23
© College of Optometrists

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