What is chronic dry eye?

Dry eye affects millions of Americans. Dry eye is caused by one of two conditions: either the eye cannot produce sufficient tears or the eye feels dry due to poor tear quality. While there is no cure for dry eye, there are dry eye treatments that can provide relief. Your Clarus vision specialist can help you choose the right dry eye treatment for you.

The Function of Tears

The continuous production and drainage of tears are important to the eye’s health. Tears keep the eye moist, help wounds heal, and protect against eye infection. In people with dry eye, the eye produces fewer or lower quality tears and is unable to keep its surface lubricated and comfortable.

The tear film consists of three layers:

  • Outer, oily (lipid) layer that keeps tears from evaporating too quickly and helps tears remain on the eye
  • Middle (aqueous) layer that nourishes the cornea and conjunctiva
  • The bottom (mucin) layer helps to spread the aqueous layer across the eye to ensure that the eye remains wet

As we age, the eyes usually produce fewer tears. Also, in some cases, the lipid and mucin layers produced by the eyes are of such poor quality that tears cannot remain in the eye long enough to keep the eye sufficiently lubricated.



Surprisingly, some people with dry eye may have tears that run down their cheeks. This is because the eye may be producing less of the lipid and mucin layers of the tear film which help keep tears in the eye. When this happens, tears do not stay in the eye long enough to thoroughly moisten it.

Other symptoms can include:

  • Scratchy or sandy feeling as if something is in the eye
  • Stinging or burning of the eye
  • Episodes of excess tearing that follow periods of very dry sensation
  • Stringy discharge from the eye
  • Pain
  • Redness
  • Heaviness of the eyelids
  • Blurred, changing or decreased vision (loss of vision is uncommon)
Treatment Options