Dry Eye
Dry Eye is a collection of symptoms that make up an eye condition stemming from an imbalance in the quantity or quality of tears bathing the eye. These symptoms include dry, red, gritty, and even watery eyes. Often, Dry Eye sufferers report the feeling of something foreign within the eye or eye-strain. Some people do not produce enough tears to keep the eye comfortable.
The balance of tear production and tear loss [through drainage and evaporation] maintains the moisture level in the eyes. When this balance is not sustained, dry spots appear on the surface of the eye and cause irritation.
A healthy eye constantly produces tears that lubricate. Excessive tears occur when a foreign body irritates the eye or when a person cries.
Dry Eye symptoms :
a. Stinging or burning eyes.
b. Scratchiness.
c. Stringy mucus in or around the eyes.
d. Eye irritation from smoke or wind.
e. Excess tearing.
f. Difficulty in wearing contact lenses
When the eye is irritated, the lachrymal gland produces a large volume of tears, which overwhelms the tear drainage system. These excess tears then overflow from your eye.

Dry Eye syndrome :

Decreased sensitivity of the cornea can also lead to insufficient production of tears. Some types of contact lens wear can bring on this lack of sensitivity.

Excessive evaporation of tears can also cause dry eye syndrome. Such evaporation may be caused by meibomitis, which results from infection and inflammation of the meibomian glands in the eyelids. People with unusually large eyes, as well as those who suffer from thyroid disease, may also experience dry eye syndrome caused by excessive evaporation.

Dry eye can also result from unusual facial anatomy or irregularities in the cornea, resulting in uneven or inadequate tear coverage of the eye. Some patients suffer from dry eye as a result of medications, such as, antibiotics, antihistamines, diuretics, and anti-diarrhea, which can dry up the mucous membranes. Hormonal changes can also affect secretions from the tear glands. Since these medications are often necessary, the dry eye condition may have to be tolerated or treated with "artificial tears".

People with dry eye are often more prone to the toxic side effects of eye medications, including artificial tears. Special preservative-free artificial tears may be required.
Treatment of Dry eye :
Depending on the causes, Dry Eye syndrome can be treated as a temporary problem or a lifelong disease requiring long-term treatment. Either way, tears must be conserved or replaced in order to provide relief.
Adding tears
Artificial tears are probably the most common forms of treatment for Dry Eye syndrome. These Eye drops are similar to your own tears. They lubricate the eyes and help maintain moisture. Preservative-free eye drops are available if you are sensitive to the preservatives in artificial tears.

Conserving the tears with Punctual Occlusion

In cases of persistent Dry Eye symptoms, permanent, reversible closure of the tear duct or punctual occlusion may be the best solution. Punctual occlusion allows you to retain your own, natural tears without the bother or expense of constantly replacing the tear film with artificial tears.

Tears drain out of the eye through a small channel into the nose. We may close these channels either temporarily or permanently. The closure conserves your own tears and makes artificial tears last longer.

A person with dry eye should avoid anything that may cause dryness, such as, an overly warm room, hair dryers, wind or a direct fan / air conditioner draft. Smoking is, especially, bothersome.

Some people with dry eye complain of "scratchy eyes" when they wake up. Using an artificial tear ointment at bedtime can treat this symptom.