Dry eye syndrome is a condition in which the eye does not produce enough tears, or the tears are too thin to lubricate and nourish the eye. Tears are necessary for maintaining the health of the front surface of the eye and for providing clear vision. Dry eye syndrome is a common and often chronic problem, particularly in older adults.
Tears provide lubrication and reduce the risk of eye infection. They wash away foreign matter in the eye as well as keep the surface of the eye smooth and clear. With each blink of the eyelids, tears are spread across the front surface of the eye known as the cornea. Excess tears in the eyes flow into small drainage ducts in the inner corners of the eyelids, which drain in the back of the nose.