guidelines

red eye (primary care triage)

nice cks-aligned red eye triage: identify sight-threatening causes (keratitis, uveitis, angle-closure glaucoma), contact lens risk, and urgent referral triggers.

last reviewed: 2026-02-14
based on: NICE CKS Red eye (accessed 2026)
reviewer: Dr Kola Tytler MBBS CertHE MBA MRCGP
view official NICE source

Executive summary

  • Red flags = same-day ophthalmology/ED: reduced visual acuity, severe pain, photophobia, corneal opacity/ulcer, irregular pupil, headache + nausea/vomiting (angle closure), contact lens wearer with pain/redness.
  • Always document visual acuity (each eye) and pupil reactions.
  • Most benign: viral conjunctivitis, mild bacterial conjunctivitis, dry eye/blepharitis — but only after red flags excluded.

Rapid assessment (60–90 seconds)

  • Vision: any reduction from baseline? (Test each eye.)
  • Pain/photophobia: suggests keratitis/uveitis/angle-closure rather than simple conjunctivitis.
  • Contact lenses: treat as keratitis until proven otherwise if painful; urgent assessment needed.
  • Discharge type: watery (viral/allergic), mucopurulent (bacterial), none + gritty (dry eye).
  • Pupil/shape: irregular pupil or fixed mid-dilated pupil + headache → urgent glaucoma pathway.

Common patterns (and what to do)

  • Viral conjunctivitis: watery discharge, gritty, often bilateral; hygiene advice and return precautions.
  • Allergic conjunctivitis: itching, chemosis; antihistamine/mast-cell stabiliser drops where appropriate.
  • Blepharitis/dry eye: lid hygiene, lubricants.
  • Keratitis/uveitis/angle closure: urgent referral (do not delay).

References (Harvard):

  • NICE CKS (2026) Red eye. https://cks.nice.org.uk/topics/red-eye/

FAQs

Do I need fluorescein staining in primary care?
If available and you are trained, it can help detect corneal abrasion/ulcer, but do not delay urgent referral in a contact lens wearer with pain or any sight-threatening features.
Are antibiotics always needed for conjunctivitis?
No. Many cases are viral or self-limiting. Focus on red flag exclusion, hygiene advice, and selective treatment per local formulary.
What is the single biggest miss?
Contact lens–associated keratitis and acute angle-closure glaucoma—both require same-day urgent assessment.

Transparency

This page is an educational, clinician-written summary of publicly available NICE guidance intended for trained healthcare professionals. It uses original wording (not copied text) and should be used alongside the full NICE source, local pathways, and clinical judgement. Doses provided are for general reference; always check the BNF/SPC.