Overview
When an allergen lands on the eye surface, mast cells release histamine and the conjunctiva reacts: itching, redness, swelling and watering. Unlike infection, allergy is almost always in both eyes, and the dominant symptom is itch rather than grit or pain.
Seasonal allergy tracks pollen counts; perennial allergy from dust mites or pets runs all year. Both are common alongside hay fever, asthma and eczema.
What are the common symptoms?
- Intense itching — the defining symptom
- Watery discharge and red eyes, both sides
- Puffy eyelids, and a swollen jelly-like appearance to the white of the eye
- Sneezing, a runny nose and an itchy throat alongside
- Symptoms that follow a season, a room, or a specific animal
What causes it, and who is at risk?
- Tree, grass and weed pollen
- Dust mites and mould
- Animal dander
- Cosmetics, contact lens solutions and eye drop preservatives
- A personal or family history of allergy, asthma or eczema
How is it treated?
Rubbing makes it worse — it releases more histamine and, over time, can weaken the cornea. Cold is the fastest relief.
- Cold compresses and preservative-free lubricating drops to flush allergen away
- Antihistamine and mast-cell stabiliser drops, started before the season where possible
- Short courses of steroid drops for severe flares, under supervision
- Oral antihistamines, bearing in mind they can worsen dryness
- Avoidance measures: showering after being outdoors, mite-proof bedding, keeping windows shut on high-pollen days
- Switching to daily disposable contact lenses during the season
This page is general information, not a diagnosis. Only an eye care professional who has examined you can tell you what is actually going on.