If the tear ducts fail to produce enough fluid to keep the eyes wash, the result is dryness of the eyes and irritation that causes itching and a burning sensation. This condition is more common in women, particularly after menopause, and the incidence increases with age in both sexes.

Dry eyes can also be a symptom of other conditions, such as rheumatoid arthritis and lupus, and they can be a side effect of certain drugs, including common antidepressants, beta-blockers, and marijuana. Dry eyes are often a problem for people who wear contact lenses.

Xerophthalmia is the medical term for dryness of the surface of the eye resulting from vitamin-A deficiency. In this condition, the cornea becomes dry, hazy, and, if the condition is severe enough, the cornea and/or the conjunctiva, the transparent membrane adjacent to the cornea, begin to disintegrate. Foamy white patches on the surface of the eye, called Bitot’s spots, may develop.