Dry eyes are caused by a lack of adequate tears. Your tears are a complex mixture of water, fatty oils and mucus. This mixture helps make the surface of your eyes smooth and clear, and it helps protect your eyes from infection. For some people, the cause of dry eyes is decreased tear production.
Dry eyes can happen when tears evaporate too quickly, or if the eyes produce too few tears. It is common in humans and in some animals. It can affect one or both eyes, and it can lead to inflammation.Dry eye syndrome can occur at any age, and in people who are otherwise healthy.
Why Do I Wake Up with Dry Eyes? Dry eye is a common condition that happens when your eyes don't produce enough tears or the tears evaporate too quickly. ... Some of the most common reasons for waking up with dry eyes are: your eyelids aren't remaining tightly closed during sleep (nocturnal lagophthalmos).
Signs and symptoms, which usually affect both eyes, may include: A stinging, burning or scratchy sensation in your eyes. Stringy mucus in or around your eyes. Sensitivity to light.