Allergic reactions can occur throughout various parts of the body. Whether it is a reaction that causes closing of the airways or a rash on the skin, all allergic reactions are responses from the body. In the eyes, a common allergic reaction is referred to as allergic conjunctivitis. Below is a summary of the various subtypes of allergic conjunctivitis and their associated symptoms and treatment.
Acute Allergic Conjunctivitis
This is the most common subtype of allergic conjunctivitis and refers to seasonal allergies as well as ocular reactions to allergens that are present throughout the year (i.e. cat hair). The first signs or symptoms can involve swelling of the eyelid, red and itchy eyes, increased tearing, bumps on the eyelid and associated nose and throat discomfort. The allergen is often airborne and is different for each individual.
Treatment for acute allergic conjunctivitis includes avoiding the allergen when possible and a cold compress for comfort. Artificial tears can also improve comfort as well as help to irrigate the allergen out from the eyes. The next step up would be to use oral or topical (eye drop) medications.
A great short term option would be an antihistamine, which provides relief from symptoms in cases where the reaction is sudden and unexpected. Mast cell stabilizers are useful for long term prevention and should not be used for quick relief. Often, antihistamines and mast cell stabilizers are combined together in an eye drop to provide the best protection against allergic reactions.
In cases when the allergic reaction includes a more severe inflammatory response, a steroid or NSAID medication may also be used to calm the symptoms.
Vernal Keratoconjunctivitis
Sometimes seen in young male children, vernal keratoconjunctivitis refers to a recurrent condition that shows symptoms of extreme itching, tearing, light sensitivity, thick discharge and the feeling of something being stuck in the eye.
It is common to see this condition associated with eczema or asthma with a peak in incidence during the late spring and summer months. There is a potential for this condition to cause permanent damage so treatment is key.
Treatment includes avoidance of the allergen if possible and cold compresses for comfort. If there is inflammation of the eyelid, lid hygiene will be important and scrubs can be used.
Mast cell stabilizers and NSAIDs are helpful to reduce the frequency of flare-ups. Antihistamines and steroids are able to provide immediate relief. Immunosuppressants may need to be prescribed if this is recurrent and does not respond to the traditional treatment options for allergic reactions.
Atopic Keratoconjunctivitis
This is often seen in adulthood, with a peak incidence for patients in their 30s to 50s. It is often associated with eczema and asthma or other atopic conditions.
The symptoms and signs are similar to vernal keratoconjunctivitis but more severe. The eyelids are often red and scaly, and could scar and turn inwards or outwards. The individual will experience watery discharge with itchy eyes and light sensitivity.
Treatment for atopic keratoconjunctivitis is similar to vernal keratoconjunctivitis, although it is less responsive to management strategies. Cold compresses can be used for comfort and lid hygiene is important.
Antihistamines and steroids are used for immediate relief whereas mast cell stabilizers and NSAIDs are used to limit outbreaks. Immunosuppressants may need to be used if traditional management of allergies is insufficient.