Causes
... Tears are much more than just water. They''re a complex mixture of water, fatty oils, proteins, electrolytes, bacteria-fighting substances and growth factors that regulate various cell processes. This...

When to seek medical advice
... Although dry eyes don''t usually cause permanent damage, diminished vision may prompt you to seek medical treatment. See your doctor if you''ve had prolonged symptoms of dry eyes, including red, irrit...

Screening and diagnosis
... If your eyes feel dry and irritated, your eye doctor can test both the quantity and the quality of your tears. The doctor may measure your tear production using the Schirmer tear test. In this test, b...