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Acute red eye

    • Common causes of a red eye include conjunctivitis (viral, bacterial, allergic or chemical), foreign body, corneal ulceration and subconjunctival haemorrhage.
    • Uncommon causes include iritis, scleritis, episcleritis and glaucoma.
    • A discharging non-red eye in infants is most likely due to nasolachrymal duct obstruction.


    Obtain a history concentrating on the possibility of ocular trauma, contact lens wear, time course of the redness, and the presence of eye pain, itch and discharge.

    Eye examination

    • Carefully inspect eyelids, everting to examine the undersurface.
    • Examine the conjunctiva, pupil, iris and cornea, using the slit lamp whenever possible.
    • Stain with fluroscein if corneal abrasion or ulcer possible.
    • If trauma is possible examine for enophthalmos, diplopia, subconjunctival haemorrhage, hyphema and retinal detatchment.
      (See penetrating eye injury guidelines)
    • Always measure the visual acuity with age-appropriate charts.
    Signs and symptoms Diagnoses to be considered

    pain, photophobia, watery discharge

    - foreign body
    - traumatic corneal ulcer
    - herpetic ulcer
    - acute glaucoma

    purulent discharge

    - infective conjunctivitis

    itchiness, eyelid swelling and redness, watery discharge

    - allergic conjunctivitis

    dull, aching eye pain

    - iritis, scleritis, episcleritis

    subconjunctival haemorrhage

    - trauma
    - vigorous coughing or vomiting

    focal conjunctival injection or iris injury

    - trauma

    Conjunctivitis (non neonatal)

    • May be difficult to clinically differentiate bacterial, viral and allergic conjunctivitis.
    • Suspect bacterial conjunctivitis if purulent discharge. Treat with eye toilet and topical chloramphenicol.
    • Suspect herpes simplex infection if lid vesicles. If a dendritic ulcer is present treat with acyclovir ointment and contact ophthalmology.
    • Suspect allergic conjunctivitis if bilateral watery discharge with burning or itchy sensation and eyelid swelling, especially in an atopic child. Consider treating with antihistamines (oral or topical) and artificial tears.
    • Chloramphenicol eye drops can cause contact hypersensitivity reactions; if a hypersensitivity reaction is suspected, cease chloramphenicol and seek advice from an ophthalmologist.

    Conjunctivitis (neonatal)

    • Pathogens include staphylococcus, haemophilus, chlamydia, streptococcus, gonococcus and herpes simplex..
    • Obtain conjunctival scrapings for gram stain, giemsa stain and cultures.
    • Use chlamydia kit for immmunofluorescence and treat chlamydial conjunctivitis with eye toilet and oral erythromycin.
    • Consider gonococcal conjunctivitis if severe purulent discharge with conjunctival and lid oedema. Perform an urgent gram stain and contact ophthalmology þ may need septic work up and systemic Ceftriaxone 50 mg/kg/dose (2g) iv 12H.
    • Treat other organisms with topical chloramphenicol.

    Foreign body

    • Anaesthetise conjunctiva with amethocaine 1% or benoxinate 0.4%. (one drop).
    • Examine surface of eye and under lids, using slit lamp if possible.
    • Stain with fluroscein to assess corneal injury.
    • Remove foreign body with moistened cotton bud, apply chloramphenicol ointment and pad for four hours.
    • Need daily review until epithelium healed.
    • Refer embedded or metallic foreign bodies to ophthalmologist.

    Corneal ulceration

    • May be caused by trauma (including foreign body) or herpes simplex infection.
    • Visible after fluroscein staining.
    • If traumatic apply chloramphenicol ointment and review in 24 hours.
    • If dendritic ulcer contact ophthalmology.

    Chemical burns

    • Irrigate eye with copious amounts of saline for at least 15 minutes, until pH normal.
    • Particulate alkaline matter must be totally removed (may require GA).
    • Assess damage with fluroscein staining and slit lamp examination þ if corneal damage contact ophthalmology.


    • Presents with pain, photophobia, blepharospasm and lacrimation.
    • Pupil may be small and poorly reactive.
    • May occur in association with juvenile chronic arthritis.
    • Contact ophthalmology.

    Scleritis and episcleritis

    • Present with localised areas of inflammation with tenderness and lacrimation.
    • Strongly associated with systemic disease.
    • Contact ophthalmology.


    • Presents with an enlarged, hazy cornea, photophobia and lacrimation.
    • Contact ophthalmology


    • Consider if hyphema or focal conjunctival injection.
    • Consider penetrating injury (see penetrating eye injury guidelines).
    • Contact ophthalmology.