May 17, 2012

Allergic Conjunctivitis

By Richard Phinney, M.D.
Eye Surgeons Associates

If your eyes have been itchy, red, and watery over the past few weeks, it could be that you’re suffering from allergic conjunctivitis. Seasonal allergies affect more than 35 million Americans each year. Tree pollens in April and May, grass pollens in June and July, and mold spores and weed pollens in July and August add up to a five month stretch of eye irritating allergens.

The moist tissues on the surface of the eye, in the nose, and throat are important elements in the body’s immune defense mechanism. The mucus on the surfaces is able to trap airborne particles such as bacteria, virus, pollen, and pollutants. All of these particles have a molecular structure which may or may not be recognized by the elements of the body’s immune surveillance.

In the case of allergy, molecules on the surface of particles such as pollen trapped in the mucus are recognized and become bound to circulating molecules known as immunoglobulins. This aggregation may then be recognized by cells which respond by releasing many very powerful chemicals. These chemicals such as histamines cause blood vessels to become leaky and the surrounding tissues swell. Some of the chemicals released also cause itching.

Most have heard of antihistamine medications. These are frequent elements in prescriptions and over-the-counter drugs designed to combat the symptoms of allergy. Neutralizing the effects of histamines by these drugs helps to minimize the swelling of tissues; but the oral medicines of this type frequently also cause drowsiness.

Another method of interfering with the allergic response stabilizes the cells which release histamines and other chemicals in the first place. Many of the newer prescriptions and some over-the-counter brands combine these two actions for greater effectiveness.

The better understanding of how the body responds to substances which cause an allergic reaction has brought improved treatments for these symptoms which plague so many people. Symptoms of seasonal allergies are also quite similar to dry eye symptoms which are treated very differently. It is important to see your eye doctor for a medical evaluation if your attempts to control symptoms are unsuccessful.

Richard Phinney, M.D. of Eye Surgeons Associates is Board certified and fellowship trained in cornea/refractive. His specialty interests include refractive surgery procedures including: laser in-situ keratomileusis (LASIK); photorefractive keratectomy (PRK); astigmatic keratotomy (AK); cataract/IOL using multifocal implants; and advanced lamellar transplant surgery (DSEK). Dr. Phinney practices at our office in Rock Island, Illinois. For more information, please see our website: esaeyecare.com.