Introduction
Allergic conjunctivitis is inflammation of the lining of the eye (conjunctiva) due to allergy.
It could occur on its own or in association with generalized atopy (asthma, eczema, spring catarrh)
Clinical features
- Itching of the eyes with grittiness
- May be associated with itchy ears throat, or sinusitis and
- Brownish discolouration of the conjunctiva
- Eyelid oedema
- Red eyes occasionally, with watering when acute
- Follicles on the bulbar conjunctiva especially at the limbus
- Papillae on the tarsal conjunctiva (seen on eversion of the eyelid)
- Phlycten in tuberculosis- appears as a yellow nodule with surrounding leash of engorged vessels
Aetiology
Exogenous allergens
- Topical drugs: atropine, penicillin
- Cosmetics
- Pollen from plants and flowers (hay fever or spring catarrh)
- House dust mite and animals
Endogenous allergens
- Phlyctenular conjunctivitis caused by tuberculo-protein
Differential diagnoses
- Trachoma
- Other forms of conjunctivitis
Complications
- Pannus formation
- Keratoconus
- Corneal plaques
Investigation
- Skin sensitivity test to detect allergen
Drug treatment
Antihistaminics preparations
Antazoline sulfate 0.5%, xylometazoline
hydrochloride 0.05%
Adult and child over 5 years:
- Apply 2-3 times daily
Ketotifen eye drops
Adult & Child 3 – 18 years:
- Apply twice daily
Or
Olopatadine eye drops
Adult and Child 3 – 18 years:
- Apply twice daily; max. duration of treatment 4 months
Corticosteroids/NSAIDS
Low dose, topical, if severe
Diclofenac sodium 0.1% eye drops
Adult and child:
- Apply once daily
Phlyctenular Conjunctivitis:
- Treat for tuberculosis using standard regimen
Caution and Contraindication to treatment
- Avoid overuse/misuse of steroids.
- Use only in severe cases
- Xylometazoline is a sympathomimetic; use
with caution in patients susceptible to angle closure glaucoma - Systemic absorption of antazoline and xylometazoline may result in interactions with other drugs
Prevention
- Avoid allergen(s) as much as possible in cases where it/they have been identified