Eye pain - red flag symptoms

Dr Pipin Singh discusses the red flag symptoms to be aware of in patients presenting with eye pain.

Red flag symptoms

  • Sudden onset
  • Visual loss
  • Photophobia
  • Fever
  • Recent trauma
  • Vomiting
  • Associated red eye
  • Contact lens wearer
  • History of malignancy
  • History of flashers or floaters


A focused history and examination will often reveal the aetiology during your consultation. Explore the patient’s ideas, fears and expectations around their symptom and why they have chosen to present now. A lot of patients will have researched their symptoms prior to presenting.

Questions to ask

  • Where is the pain? How long has it been present?
  • Is it unilateral or bilateral?
  • Did the pain develop suddenly or over time? If suddenly, what were they doing at the time?
  • Has there been any reduced vision? If so, explore this further.
  • Have they noticed any associated blurred vision or double vision? Have they noticed any flashers or floaters?
  • Has there been any recent preceding trauma?
  • Have they noticed any redness to the sclera?
  • Has there been associated photophobia? Has there been any stickiness or grittiness?
  • Have they noticed any redness around the eye and if so, is this redness spreading? Does the surrounding skin look red or feel warm?
  • Is the patient a contact lens wearer?
  • Is there a history of migraine and if so, does it feel the same as previous headaches? Does the eye water?
  • Is the pain getting worse? Are they systemically unwell?
  • Has there been any recent coughs or colds? Is there any nasal discharge? Is there any snap tenderness or jaw claudication?
  • Is there any history of malignancy? Have they experienced this symptom before and if so was there a diagnosis attributed to it?
  • Have they seen an optician regarding this particular symptom?
  • Is there any history of ophthalmological problems? How is the symptom affecting function? Check on employment status. (Their work may be related to the problem, for example if there is a foreign body in the eye).
  • Do they drive?


The examination will be guided by the history. This needs to be focused and the following list acts as a guide.

  • Does the patient appear unwell?
  • Inspection: is there any swelling or redness? Check the pupil. Does it appear regular? Is the sclera injected? Are there any obvious external abnormalities such as cystic lesions? You may need to evert the tarsal plate. Check the eyelashes.
  • Palpation: palpate the adjacent sinuses. Is there any tenderness? Palpate the temporal artery looking for tenderness with or without loss of pulsation.
  • Check eye movements. Is there any pain associated with movements, with or without diplopia?
  • Check the pupils. Are they equal and reacting to light and accommodation?
  • Check visual acuity using a Snellen chart.

A neurological examination may be necessary if the symptoms are more suggestive of headaches.

Primary care investigations to consider

  • Blood work including ESR
  • Fluorescein staining
  • Eye swab
  • CT or MRI of the head depending on level of concern and local referral protocols

When to refer

  • Urgent same day ophthalmological review may be necessary depending on history and examination findings
  • if you suspect temporal arteritis, then urgent discussion with vascular surgeons may be necessary
  • Urgent maxillo-facial review is needed if periorbital cellulitis is suspected
  • Urgent admission for CT/MRI of the head may be required if you suspect a intracranial bleed
  • Consider urgent neurological referral if other intracranial pathology is suspected such as a space-occupying lesion.

Ophthalmological causes

Lid or eyelash problems

  • Styes
  • Meibomian cysts
  • Skin malignancy such as squamous cell carcinoma or basal cell carcinoma
  • Blepharitis
  • Trichiasis

Anterior chamber pathology

  • Acute infective conjunctivitis
  • Corneal ulcers (including dendritic ulcers)
  • Keratitis
  • Iritis
  • Scleritis
  • Acute glaucoma
  • Foreign body
  • Corneal abrasion

Other causes

  • Migraine
  • Cluster headaches
  • Acute sinusitis
  • Temporal artery tenderness
  • Metastatic disease such as cerebral metastases
  • Periorbital cellulitis
  • Ophthalmic shingles

Further reading

NICE Clinical knowledge summaries Management of red eye https://cks.nice.org.uk/red-eye - !scenario

Patient.info Examination of the eye https://patient.info/doctor/examination-of-the-eye

BMJ Best practice Assessment of red eye http://bestpractice.bmj.com/best-practice/monograph/496.html

Kuffova L, Forrester J, Dick A Assessing the painful, uninflamed eye in primary care BMJ; 2015: 351: h3216. http://www.bmj.com/content/351/bmj.h3216

  • Dr Pipin Singh is a GP in Northumberland

Click here to take a test on this article and claim a certificate on MIMS Learning

Have you registered with us yet?

Register now to enjoy more articles and free email bulletins


Already registered?

Sign in

Follow Us: