Signs and symptoms of dry eye
Persistent dryness, scratchiness and a burning sensation on your eyes are common symptoms of dry eye syndrome. These symptoms alone may be enough for your eye doctor to diagnose dry eye syndrome. Sometimes, he or she may want to measure the amount of tears in your eyes. A thin strip of filter paper placed at the edge of the eye, called a Schirmer test, is one way of measuring this.
Some people with dry eyes also experience a "foreign body sensation" – the feeling that something is in the eye. And it may seem odd, but sometimes dry eye syndrome can cause watery eyes, because the excessive dryness works to overstimulate production of the watery component of your eye's tears.
What causes dry eyes?
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. Recent research suggests that smoking, too, can increase your risk of dry eye syndrome. Dry eye has also been associated with incomplete lid closure following blepharoplasty – a popular cosmetic surgery to eliminate droopy eyelids.