Dry eyes is a common condition in which tears do not provide sufficient lubrication for the eyes. It may be caused by insufficient tear production, an imbalance in the makeup of tears, or increased tear evaporation. 

Decreased tear production may be the result of age or certain medical conditions, such as diabetes, lupus, rheumatoid arthritis, thyroid disorders or a vitamin A deficiency. Certain medications may also cause dry eyes, including some antihistamines, antidepressants and birth control drugs. 

Symptoms of dry eyes include a stinging sensation in the eyes, stringy mucus around the eyes, light sensitivity, red eyes, watery eyes, and blurred vision. 

Treatment of dry eyes involves taking steps to prevent the condition occurring, such as avoiding smoke, taking breaks during long tasks (such as sitting at the computer or reading) and wearing protective eyewear, although in some cases medication may be necessary. Drug classes commonly used treat dry eyes include Artificial Tears and Ocular Lubricants, and Miscellaneous Ophthalmologicals for Dry Eye Disease.