HEALTHNET

Why my eyes often feel dry?

Our eyes would feel dry when not enough tear is being produced in the tear film, or when the rate of evaporation of tears is too high.

(Posted on 1 February 2007)

Q1. Why my eyes often feel dry?

A1. Healthy eyes are protected by a film of tear which lubricates them. The tear in the film is different from the tear that is produced when you cry, or when your eyes are irritated. Therefore patients can still experience dry eyes despite tears pouring down their cheeks.

Our eyes would feel dry when not enough tear is being produced in the tear film, or when the rate of evaporation of tears is too high. Normally the tear film is kept moist by blinking. Task that require intense visual fixation such as driving, reading, especially in front of the computer would decrease the rate of blinking and contribute to dryness.

Complaint of dry eyes is most common in dry and windy weather. The discomfort is often aggravated by the environment at work, e.g. in airplane cabins, or windy dusty polluted areas.

Many diseases of the eye can cause dry eyes. Sometimes this can be the early symptoms of systemic diseases. You should therefore seek advice from your doctor to exclude any underlying conditions if the condition is irritating enough. Allergic reaction to eyedrops or ointments can also cause dry eyes.

Q2. What diseases can cause dry eyes? Am I suitable to wear contact lens then?

A2. The eyelids play an important role in maintaining the tear film. People with diseases affecting the eyelids are prone to dry eyes.

Patients with weakness or paralysis of the muscles that control the eyelids and face may not be able to close their eyes completely, and are at risk of dry eyes. Infection and inflammation of the lid margin, called "lepharitis" is also a common cause of dry eyes in the elderly.

Dry eyes can be caused by Sjögren's syndrome, in which immune cells attack and destroy the glands that produce tears and saliva in a patient. The condition is associated with rheumatic disorders such as rheumatoid arthritis. Refractive eye surgeries may cause decreased tear production and dry eyes which take months to recover.

Contact lens floats on the tear film. When the tear film becomes too thin, the contact lens may cause abrasions to your cornea. If you feel that your eyes are dry, you should not put on contact lens until your eyes have been evaluated by your doctor or optometrist. If the condition is mild, the doctor may recommend artificial teardrops or eye ointments that are suitable to you and are compatible with your contact lens.

Q3. Is there any eye exercise suggested? What else can I do to relieve my dry eyes?

A3. The most effective eye exercise against dry eyes is blinking.

After about five minutes of continuous work, close your eyes for about five seconds, followed by conscious blinking five times. In between you should also consciously remind yourself to blink, so as to spread your tears more evenly to maintain your tear film.

Most people are spending too much time in front of the computer screen these days. The frequency of blinking diminishes unconsciously with intense visual fixation. Putting the monitor below eye level would help relieve dry eyes because our upper eyelid would cover part of the eyeball when looking down.

Modify your home and work environment if you can. Add a humidifier to increase the humidity above 50% in dry weather. Avoid having air conditioners or fans blowing toward your face. Wearing a pair of glasses would help. Some of them are specially designed to contain moisture and are especially suitable for outdoor activities. Remember to drink plenty of fluids. Avoid coffee and alcohol, which dehydrates your body. Do not smoke, and avoid dusty and smoky areas. Do not rub your eyes. This would cause more irritation and can often introduce infection.

Your doctor might have prescribed eye drops or artificial tears. Use them before your eyes feel dry.

Source: Quality HealthCare