Red Eye

• Red Eye


  Subconjunctival Haematoma
• Subconjunctival Haematoma


  • Blood vessels in sclera become broken, so the eye appears red and bloodshot
  • No pain or visual disturbance
  • Occurs suddenly
• Cause of Subconjunctival Haematoma

  Small blood vessels rupture, maybe as a result of temporary increase in pressure such as sneezing, coughing
• Treatment for Subconjunctival Haematoma

  No treatment, but refer if a result of trauma, or if patient is diabetic
• Simple Vasodilation


  General redness of the white of the eye, frequently as a result of local irritation or allergy, or sometimes due to sleep deprivation
• Treatment for Simple Vasodilation

  • Local antihistamine (antazoline) or sodium cromoglycate can be used to help manage it as well as vasoconstrictor to reduce vasodilatation (eye whiteners)
  • Should only be used in the short term as it may mask serious conditions and long term use may lead to narrow angle glaucoma
  • Witch hazel reputed to have mildly astringent properties
• Conjunctivitis


  Inflammation of the conjunctiva (a thin, vascular and mucous membrane which covers the external surface of the eye and the eyelids), characterised by varying degrees of ocular redness, irritation, itching and discharge
• Epidemiology of Conjunctivitis


  • Affects both sexes equally and may present in any age of patient, although bacterial conjunctivitis is more common in children and viral conjunctivitis is more prevalent in adults
  • All types are essentially self-limiting, although VC can be recurrent and persist for many weeks
• Causative agents of Conjunctivitis

  • Virus (most commonly adenovirus)
  • Bacteria (Staph. Aureus, Strep. pneumoniae, Haemophilus influenzae)
  • Chlamydia
  • Allergic agents (e.g. pollen)
• Viral Conjunctivitis


  • Both eyes are affected, but one eye is often affected first, releasing a watery discharge, and the pain is a gritty feeling
  • The redness is generalised
  • Associated with cough and cold symptoms
• Bacterial Conjunctivitis


  • Normally both eyes are affected, but one eye can occasionally become affected, producing a mucopurulent discharge
  • The pain is a gritty feeling and the redness is generalised and diffuse
  • Not associated with other symptoms
• Allergic Conjunctivitis


  • Both eyes are affected, producing a watery discharge, and they become itchy
  • The redness is generalised, but greatest in fornices
  • Associated with rhinitis (may also have a family history of atopy) and hay fever symptoms
  • Excess exudation may present drainage problem, and dried exudate can restrict easy opening of eyelids
• Treatment for Bacterial Conjunctivitis


  1. Self-limiting, but treatment may speed up recovery

  2. Antibiotics are routinely given as they're considered clinically desirable to speed up recovery and reduce relapse

  3. Chloramphenicol has proven efficacy and can be used in all cases of bacterial conjunctivitis

  4. For drops, 1 drop every 2 hours for first 48 hours, reducing to qds for a max of 5 days of treatment

  5. If no response in 36-48 hours, refer

  6. Ointment can be used in conjunction with drops, applied at night to spread the ointment
• Chloramphenicol Drops


  • First-line treatment
  • Can be used in most patient groups, although they should be avoided in patients with a family history of blood dyscrasias
  • For use in pregnancy, a lack of manufacturer data means that they are not recommended, so hygiene measures should be adopted
  • If absolutely necessary, they can be used in breastfeeding women
• Propamidine and Dibromopropamidine Isethionate

  • Can also be used and are active against a wide range of organisms, including those responsible for bacterial conjunctivitis
  • Only licensed for adults and children older than 12 years
  • The dosage for eye drops is one or two drops up to four times daily, whereas the ointment should be applied once or twice daily
  • If there has been no significant improvement after 2 days, the person should be re-assessed
  • Blurring of vision may occur when first used but is transient
  • Safety for use in pregnancy has not been established, but there appear to be no reports of teratogenic effects and therefore could be used in pregnancy if deemed appropriate
  • Free from drug interactions and can be given to all patient groups, including to women who are breastfeeding
• Treatment for Viral Conjunctivitis


  • Differentiation between viral and bacterial conjunctivitis can be difficult — treatment with chloramphenicol may be beneficial
  • There's currently no specific OTC medications available to treat viral conjunctivitis, however, symptoms may be eased by bathing the eyelids to remove any discharge and using lubricant eye drops
  • Viral causes are very contagious, so hygiene measures are important, e.g. do not share towels, wash hands after touching eye etc, which will help control the spread of the virus
  • A patient will remain infectious until the redness and weeping resolve, usually in 10-12 days
• Treatment for Allergic Conjunctivitis

  1. Avoidance of allergen will, in theory, control the symptoms

  2. Use of prophylactic medication, e.g. sodium cromoglicate (mast cell stabiliser), is advocated, to be given continuously during hay fever season/while exposed to the allergen

  3. The dose is one or two drops administered in each eye four times a day for children aged 6 years of age and older

  4. Clinical experience has shown it to be safe in pregnancy, and expert opinion considers sodium cromoglicate to be safe in breastfeeding

  5. It has no drug-drug interactions and can be given to all patient groups

  6. Instillation of the drops may cause a transient blurring of vision
• Sympathomimetics


  • These agents can be used to reduce redness of the eye, but will not treat the underlying pathology that is causing the eye to be red
  • Products contain a combination of sympathomimetic and antihistamine or sympathomimetic alone
  • They should be limited to short-term use to avoid rebound effects
  • They can interact with monoamine oxidase inhibitors (MAOIs) and should not be used by patients receiving such treatment or within 14 days of ceasing therapy
• Otrivine-Antistin


  • Used in adults and children older than 12 years, the dosage is one or two drops two or three times a day
  • Patients with narrow angle glaucoma should avoid this product due to the potential of the antihistamine component to increase intraocular pressure
  • Local transient irritation and a bitter taste after application have been reported
• Naphazoline


  • The use of products containing naphazoline is restricted to adults and children older than 12 years
  • One or two drops should be administered into the eye three or four times a day
• Practical Measures for Red Eye
• Differential Diagnosis for Red Eye

  • Most likely: Bacterial or allergic conjunctivitis
  • Likely: Viral conjunctivitis, Subconjunctival haemorrhage
  • Unlikely: Episcleritis, Scleritis, Keratitis, Uveitis, Neonatal conjunctivitis
  • Very unlikely: Acute closed-angle glaucoma
• Questions to Ask for Red Eye

  • Uni or bilateral eye involvement
  • Discharge present
  • Danger symptoms (reduced visual acuity, deep aching pain within the eye)
  • Location of redness
  • Duration
  • Photophobia
  • Other symptoms (signs of upper respiratory tract infection, vomiting)
• When to Refer for Red Eye

  • Clouding of the cornea and associated vomiting — suggests glaucoma, refer immediately to emergency department
  • Redness caused by a foreign body — requires removal of body, urgent same-day referral to an optician
  • Irregular-shaped pupil or abnormal pupil reaction to light; photophobia; true eye pain; distortion of vision; redness localized around the limbal area — suggest sinister pathology, refer urgently