In dry eye syndrome, the tear glands that moisturize the eye don't produce enough tears, or the tears have a chemical composition that causes them to evaporate too quickly.
Dry eye syndrome has several causes. It occurs:
- • As a part of the natural aging process, especially among women over age 40.
- • As a side effect of many medications, such as antihistamines, antidepressants, certain blood pressure medicines, Parkinson's medications and birth control pills.
- • Because you live in a dry, dusty or windy climate with low humidity.
If your home or office has air conditioning or a dry heating system, that too can dry out your eyes. Another cause is insufficient blinking, such as when you're staring at a computer screen all day.
Dry eyes are also associated with certain systemic diseases such as lupus, rheumatoid arthritis, rosacea or Sjogren's Syndrome (a triad of dry eyes, dry mouth, and rheumatoid arthritis or lupus).
Long-term contact lens wear, incomplete closure of the eyelids, eyelid disease and a deficiency of the tear-producing glands are other causes.
Dry eye syndrome is more common in women, possibly due to hormone fluctuations. Exposure to smoke and other environmental irritants can also cause dry eyes (dust, pollen, smoke, air conditioners, heaters) as well as wind and sun exposure.
Certain medications such as anti depressants, high blood pressure medications, hormone medications can contribute to tear deficiency. Underlying lid disease will also contribute to the symptoms of dry eyes.