Like other areas of the body, the eyes can experience allergic symptoms when exposed to particular stimuli. Ocular allergies, or its medical term, allergic conjunctivitis1, is used to denote the eyes reacting to an allergen, or an allergy-causing substance. Specifically, it is the conjunctiva that reacts with an allergen that leads to allergic conjunctivitis. The conjunctiva is the clear layer of filmy tissue that covers the white of the eye. Allergic conjunctivitis is common, affecting one-fifth of the American population.
When the conjunctiva becomes inflamed from allergens such as dust, pollen, mold, smoke or animal dander (shed skin off of animals), it will cause an immuno-response, causing:
Your body has an immune system to protect it from perceived threats. During an allergic reaction, its defensive mechanism is in a hyper mode, making the immune-response more active than it would otherwise be. During the allergic conjunctivitis reaction, your body releases a substance called histamine which is used to fight off the allergen. The histamine production results in the widening or dilation of red vessels, irritation of nerves, and emission of tears.
Acute Allergic Conjunctivitis occurs during allergy seasons - late winter and late spring. This type of conjunctivitis2, occurring from grass and tree pollens is also called Hay Fever. It causes the sudden onset of burning, itching, swelling, and a runny nose.
Chronic Allergic Conjunctivitis is a much more frequently occurring type of allergic reaction. It typically occurs year-round with symptoms of burning and itching eyes and a heightened sensitivity to the light. It is caused by dust, animal dander, and even certain foods.
In order to diagnose eye allergy, we encourage Orange County patients who experience some of the symptoms listed above to book an appointment with one of our eye doctors, who will examine your eyes as well as review your allergic history. In general, people prone to allergic reactions are more likely to develop allergic conjunctivitis.
With the help of an allergist, allergy skin testing can be performed where diluted allergens are placed on the skin to see how your body reacts. A blood test may be performed to see whether your body is producing special proteins called antibodies which protect the body from allergens such as mold and dust. In rare circumstances, a pathologic diagnosis may be made by scraping of the conjunctival tissue to evaluate your white blood cells for the presence of Eosinophils, which are common during an allergic reaction.
Methods to treat allergic conjunctivitis involve warding off exposure to allergens. You can try to first follow these steps at home:
To ease the discomforting symptoms of allergic conjunctivitis, you can make a cold compress to soothe your eyes from the itching and redness. You can use lubricating eye drops for soothing purposes. There are also eye drops that can reduce the visibility of blood vessels. Our eye doctors may suggest taking over-the-counter antihistamines to reduce the allergic response but these have the potential of contributing to the development of dry eye. The most severe type of medication is mild steroid eye drops which our doctors can prescribe when other options are exhausted or as a pulse treatment to quickly get the symptoms under control.
1 What is allergic conjunctivitis? Available: https://www.healthline.com/health/allergic-conjunctivitis
2 Pink Eye (Conjunctivitis). Available: https://www.aao.org/eye-health/diseases/pink-eye-conjunctivitis
3 What Are Eye Allergies? Available: https://www.aao.org/eye-health/diseases/allergies