The major lacrimal glands lie under the skin and extend into the eye socket. Tears reach the surface of the eye via small openings from the gland. Normally, blinking helps the eyelids spread a tear film over the eye. If blinking is prevented, dry spots develop on the surface of the eye and vision decreases. The continuous production and drainage of tears is very important.
Tears keep the eyes moist, help ocular wounds heal and protect against eye infections.
Persons with dry eyes are at greater risk of developing eye infections. Dry eyes are more common in women, especially after menopause. With the use of some drugs, including antihistamines, nasal decongestants and sedatives. Sometimes after eye surgery. In some persons with malpositioned lower eyelids.