What Causes Dry Eyes?

Understanding the cause is key to managing dry eye symptoms and finding relief.

It may sound odd, but happy eyes are tear-filled eyes. Tears serve an important role to provide lubrication, reduce the risk of infection, wash away debris and keep the surface of the eye smooth for clear vision.

“Tear glands above your eyeballs continuously supply tear film that is wiped across your eyes every time you blink,” says Herbert John Ingraham, MD, an ophthalmologist and director of the Geisinger Eye Institute. “That tear film includes three layers made up of oil, water and mucus that work together to keep the eye’s surface smooth so you can see clearly and comfortably.

Dry eye occurs if the eyes’ tear film doesn’t function as it should. This could happen because your eyes don’t produce enough tears, your tears evaporate too quickly or the tear film is unbalanced. Left untreated, this very common condition can lead to inflammation and damage to the eye’s corneal surface and even cause vision issues.

Fortunately, several treatments are available to manage your symptoms, restore eye health and bring you relief.

“If you have dry eyes, be sure to establish care with an eye doctor to manage your condition,” says Dr. Ingraham. “There are many causes for dry eyes, and treatment can depend on what’s causing your discomfort.”

Dry eye symptoms

Dry eye can be an uncomfortable condition, and typically affects both eyes. If you have dry eyes, you might feel a scratchy or gritty sensation, almost as if there’s something in your eye.

“It sounds contradictory, but you also might have watery eyes,” says Dr. Ingraham. “When your eyes are irritated by dry eye, your eyes compensate by producing more tears.”

Other signs of dry eyes can include:

Eyes that sting or burn
Stringy mucus in or around the eyes
Red or irritated eyes
Light sensitivity
Blurry vision or eye fatigue
Discomfort when wearing contact lenses

Causes of dry eyes

Many factors can cause tear production to decrease, tear evaporation to increase or tear film to be unbalanced — the main culprits for dry eyes.

“Tear production can diminish as we age,” says Dr. Ingraham. “Adults over age 50, women and people with a vitamin A deficiency are at a higher risk for dry eyes.”

Hormonal changes

Hormonal changes in men and especially women during pregnancy and menopause can affect tear production.

Side effects from certain medications or surgeries

Decongestants and antihistamines for colds and allergies, as well as antidepressants and high blood pressure medications, like diuretics, can cause dry eyes.

“Talk to your doctor about all of your medications,” says Dr. Ingraham. “If a side effect is dry eye, there may be a different medicine you can try.”

Some eye surgeries, including LASIK, cataract and corneal surgery, can increase the risk for dry eyes, too.

Medical conditions

Certain health problems — such as diabetes; autoimmune disorders, including lupus and Sjögren’s disease; and thyroid issues — can damage the tear glands. That affects your ability to produce tears, causing dry eyes.

Common skin conditions, such as rosacea, can block oil glands on your eyelids and lead to an imbalance in tear film. Without enough oil, tears evaporate more quickly.

Environmental factors

Air-conditioned or smoke-filled rooms or windy, dry environments can cause your tears to dry up faster and result in dry eyes. You may also blink less frequently when reading or staring at an electronic screen for extended periods, resulting in dry eyes.

Long-term use of contact lenses has been linked to the development of dry eyes, as well.

How to treat dry eyes

Left untreated, severe dry eyes can lead to eye infections, inflammation, scratched corneas and even vision loss.

The good news: Dry eyes are treatable. For most people with occasional or mild dry eye symptoms, artificial tears are enough to bring relief. For severe and consistent symptoms, treatment will depend on what’s causing the discomfort.

Treatments for dry eyes include:

Over-the-counter eye drops: Artificial tears are the most common treatment for mild dry eye. They lubricate and soothe your eyes and can be used as often as you need. Moisturizing gel or ointment may help your eyes feel better, too.
Prescription medications: For more severe cases, prescription medications like Restasis^® or Xiidra^® can boost tear production in your eyes.
Tear duct plugs: When tears drain too quickly from your eyes, putting special silicone plugs, known as punctal plugs, in your tear ducts helps keep tears in your eyes longer, reducing the need for eye drops.
Thermal pulsation therapy: This in-office procedure involves a medical device that uses heat and pressure to unclog blocked glands on your eyelids. These glands produce oil for your tears that keeps your eye moist and helps prevents tears from evaporating.
Therapeutic contact lenses: These special contact lenses help protect and lubricate the surface of your eyes, while also correcting your vision.
Surgery: If tear duct plugs work for you, your eye doctor may recommend surgery to permanently close your tear ducts.

Lifestyle changes

If something in your environment is causing your dry eyes, there are lifestyle changes you can make to reduce symptoms, such as:

Avoiding smoke, wind and air-conditioning. Wearing wraparound sunglasses when outside protects your eyes from wind.
Using a humidifier to keep the air in your home from getting too dry.
Limiting screen time. If that’s not possible, take frequent breaks and practice the 20-20-20 vision rule: Every 20 minutes, look at an object at least 20 feet away for about 20 seconds.
Staying hydrated by drinking plenty of water daily.
Adding omega-3 fatty acids to your diet. Research has shown they can support tear production. Good sources include fatty fish, such as salmon and tuna, as well as walnuts and soybeans.

“If you have dry eyes and it’s affecting everyday activities, talk to your eye doctor,” says Dr. Ingraham. “While you may need to try several different treatments, including drops, medication and procedures, your doctor can help you find the best solution to restore eye health and bring you relief.”