Conjunctiva
Allergic Conjunctivitis
Also known as: hay fever eye, ocular allergy, seasonal conjunctivitis, perennial allergic conjunctivitis, SAC, PAC, itchy eyes, allergic eye
Filed as: Routine
Source-cited from the record's own evidence list. Clinical content programme led by Dr Ankit Mathur, PhD, Grad Cert Ocu Thera, B.S. Optom. How the clinical content is governed
Clinical decision support only
Overview
IgE-mediated type 1 hypersensitivity reaction of the conjunctiva. The most common form of ocular allergy. Presents with bilateral itching, watery discharge, and papillary conjunctival changes. Usually seasonal or perennial depending on the trigger.
Recognition
Symptoms: what patients report
- Intense bilateral itching — the cardinal symptom; differentiates allergy from most other causes.
- Watery or mildly stringy discharge.
- Diffuse pink-red conjunctival redness of both eyes, often mild.
- Eyelid puffiness and mild swelling.
- Associated nasal symptoms: sneezing, runny nose (seasonal).
- Symptoms that worsen outdoors or during specific seasons.
Signs: what the examination shows
- Papillary reaction on upper tarsal/palpebral conjunctiva (small, uniform papillae).
- Chemosis (conjunctival oedema) — can be pronounced.
- Diffuse conjunctival hyperaemia, typically mild.
- Lid oedema.
- Watery discharge.
- Cornea typically clear and uninvolved in simple allergic conjunctivitis.
What OptoGuide™ covers for allergic conjunctivitis
- Pattern reasoning: what this combination of findings points to, and its differentiators
- Don't-miss risks and escalation triggers
- Management tiers with linked Australian therapeutics
- Referral urgency, specialty, and letter drafting
Sources
- Conjunctivitis (seasonal & perennial allergic) — College of Optometrists CMG
- Allergic Conjunctivitis — EyeWiki
- Anterior Eye Disease and Therapeutics A-Z (Bruce & Loughnan) — standard reference text
- The Red Eye. Leibowitz HM. The New England Journal of Medicine. 2000;343(5):345-51.
- Castillo M et al. Topical antihistamines and mast cell stabilisers for treating seasonal and perennial allergic conjunctivitis — Cochrane Database Syst Rev 2015;6:CD009566 (olopatadine versus ketotifen, itching at 14 days)
Standard texts: Kanski's Clinical Ophthalmology: A Systematic Approach, The Wills Eye Manual, Oxford Handbook of Ophthalmology, Oxford American Handbook of Ophthalmology, Signs in Ophthalmology: Causes & Differential Diagnosis.