Allergic eye disease
What is it?
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| An 'allergic shiner' |
Allergic eye disease is very like other allergies such as hayfever, asthma and eczema in which there is an excessive immune reaction to something in the environment.
Types of allergic conjunctivitis
There are three common types of allergic conjunctivitis:
- Acute allergic conjunctivitis
- Chronic allergic conjunctivitis
- Giant papillary conjunctivitis
Acute allergic conjunctivitis
This quite spectacular reaction typically occurs in children playing in long grass or with pets. The eyes are very itchy and watery, and eyelid swelling is common. Most cases resolve spontaneously within a few hours. The best treatment is cool compresses.
Chronic allergic conjunctivitis
There are three types of chronic conjunctivitis:
- Hayfever conjunctivitis
- Drug induced conjunctivitis
- Vernal keratoconjunctivitis
Hayfever conjunctivitis
This is the most common type of allergic conjunctivitis. The main symptoms are itch and watering. They begin abruptly after exposure and resolve soon after exposure ceases. Symptoms may be seasonal or occur year round. The eyelids may swell and darken, an appearance known as 'allergic shiners'.
Most sufferers are only too familiar with what causes their conjunctivitis. Common triggers include:
- Seasonal allergic conjunctivitis - grass and tree pollens
- Perennial allergic conjunctivitis - animals, house dusts and mould
Drug induced conjunctivitis
Every eyedrop and ointment can cause an allergic response; either from a reaction to the drug itself or the preservative solution used to keep the bottle sterile.
The reaction may occur within a few days or after many months of treatment. Patients typically complain of non-specific irritation and low-grade itch.
Vernal conjunctivitis
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| Vernal conjunctivitis (limbal form) |
Vernal disease is a severe allergic conjunctivitis that usually occurs in patients with other allergies. In adults the disease is called atopic keratoconjunctivitis.
Symptoms typically begin in spring and are often severe. The eyes are extremely itchy, watery, 'burning' and very sensitive to light. In severe cases vision is reduced.
Giant papillary conjunctivitis
This much less common disease affects contact lens wearers and patients with artificial eyes. Large, cobblestone-like papillae form on the inner surface of the upper eyelid.