Dry eye syndrome (DES) is a chronic condition that develops when your eyes do not produce and maintain enough tears to keep the eye’s surface lubricated resulting in multiple symptoms that range from person to person. This can be due to a reduction in tear production or increased tear evaporation from a lack of lipid in the tears that stem from oil glands in the eyelids. The effects can range from minor dryness and discomfort to pain, blurred vision and frequent infections.
Symptoms of Dry Eye Disease
Symptoms of dry eye syndrome can vary depending on the severity of the condition but can include:
- Dry, itchy eyes
- Burning or stinging
- Watery eyes
- Blurred vision
- Foreign body sensation
The main function of tears is to maintain the health of the cornea of your eye by washing away foreign matter and ensuring that the surface of your eye remains moist, smooth and clear. Tears also rinse away dust particles from your eyes and contain enzymes that protect your eyes from bacteria that can cause infections. Dry eyes is a condition that develops when the amount of tears produced is not sufficient to maintain the moisture balance in your eye. This can result in that scratchy sensation, a continuous feeling of dryness, stinging and a sensation of a foreign body in your eye. Ironically in an effort to fight off the condition, dry eyes can cause you to produce excessive tears, which is why some people experience watery eyes.
Causes of Dry Eye Disease
Dry eyes can occur naturally as a result of aging or hormonal changes, typically in women who are pregnant, taking oral contraceptives or going through menopause. In fact, women over 50 have a 50% greater risk of dry eye disease than men do of the same age. It can also result from taking certain medications that reduce tear production such as antihistamines, blood pressure medications and antidepressants. Environmental factors can also play a role in drying out the eyes and DED is common in areas where the climate is dry, dusty and windy. Home air conditioners or heating systems and excessive time spent staring at a computer or television screen can also dry out eyes and exacerbate symptoms due to the lack of blinking while staring at our screens.
Individuals that suffer from certain medical conditions such as diabetes, blepharitis, lupus, arthritis and thyroid problems are more vulnerable to developing DED. Other causes can be due to eye surgery including LASIK, certain conditions in which the eyelids don’t close properly or extended contact lens use.
Diagnosis of Dry Eye Disease
Typically, dry eye disease can be diagnosed through a comprehensive eye exam and a description of your symptoms. On some occasions the eye doctor might decide to do a test that measures how quickly your tears evaporate from the surface of your eye. By instilling a simple dye called fluorescein (much like food coloring) the doctor is able to watch and count how long it takes the tears to start to break up after they’ve asked you to hold your eyes open after a blink. This is called TBUT or a Tear Break Up Time test. A low TBUT generally indicates a lipid (aka oil) deficiency in the tears resulting from oil glands in the eyelids not functioning properly. In another type of test, called a Schirmer test, a strip of filter paper is placed under the lid of the eye and you will be asked to close your eye for five minutes. Following the test the amount of moisture on the strip will be measured. Schirmer tests are performed less frequently than a TBUT test.
Treatment for Dry Eyes
Dry eye syndrome is an ongoing condition that treatments may be unable to cure. But the symptoms of dry eye – including dryness, scratchiness and burning – can usually be successfully managed.
Your eyecare practitioner may recommend artificial tears, which are lubricating eye drops that may alleviate the dry, scratchy feeling and foreign body sensation of dry eye. Prescription eye drops such as Restasis, Xiidra or Cequa are available which go one step further: they help increase your tear production. In some cases, your doctor may also prescribe a steroid for more immediate short-term relief.
Another option for dry eye treatment involves a tiny insert filled with a lubricating ingredient. The insert is placed just inside the lower eyelid, where it continuously releases lubrication throughout the day.
If you wear contact lenses, be aware that many artificial tears cannot be used during contact lens wear. You may need to remove your lenses before using the drops. Wait 15 minutes or longer (check the label) before reinserting them. For mild dry eye, contact lens rewetting drops may be sufficient to make your eyes feel better, but the effect is usually only temporary. Switching to another lens brand could also help.
Check the label, but better yet, check with your doctor before buying any over-the-counter eye drops. Your eye doctor will know which formulas are effective and long-lasting and which are not, as well as which eye drops will work with your contact lenses.
To reduce the effects of sun, wind and dust on dry eyes, wear sunglasses when outdoors. Wraparound styles offer the best protection.
Indoors, an air cleaner can filter out dust and other particles from the air, while a humidifier adds moisture to air that’s too dry because of air conditioning or heating.
For more significant cases of dry eye, your eye doctor may recommend punctal plugs. These tiny devices are inserted in ducts in your lids to slow the drainage of tears away from your eyes, thereby keeping your eyes more moist.
If your dry eye is caused by meibomian gland dysfunction (MGD), your doctor may recommend warm compresses and suggest an in-office procedure to clear the blocked glands and restore normal function.
Doctors sometimes also recommend special nutritional supplements containing certain essential fatty acids to decrease dry eye symptoms. Drinking more water may also offer some relief.
If medications are the cause of dry eyes, discontinuing the drug generally resolves the problem. But in this case, the benefits of the drug must be weighed against the side effect of dry eyes. Sometimes switching to a different type of medication alleviates the dry eye symptoms while keeping the needed treatment. In any case, never switch or discontinue your medications without consulting with your doctor first.
Treating any underlying eyelid disease, such as blepharitis, helps as well. This may call for antibiotic or steroid drops, plus frequent eyelid scrubs with an antibacterial shampoo.
If you are considering LASIK, be aware that dry eyes may disqualify you for the surgery, at least until your dry eye condition is successfully treated. Dry eyes increase your risk for poor healing after LASIK, so most surgeons will want to treat the dry eyes first, to ensure a good LASIK outcome. This goes for other types of vision correction surgery, as well.
Preventing Dry Eyes
If the cause of your dry eyes is something external or environmental, eliminating that cause may solve the problem and resolve the symptoms. Avoid dry environments, hair dryers, heaters and fans, (particularly directed toward the eyes) and smoky environments and wear eye protection such as wrap around glasses or goggles when in dusty or windy areas. Use a humidifier to add moisture to dry indoor air. If working on computer or watching television, make sure to blink purposefully as our natural tendency is to reduce our blink rate when staring at a screen. Also avoid rubbing your eyes as this can further irritate them. Staying hydrated by drinking at least 8 to 10 glasses of water per day can also help.
Dry eye disease won’t have a permanent effect on your vision, but there is no reason to endure dry, itchy and uncomfortable eyes, especially since there are so many treatment options to increase moisture and comfort. It’s also important to realize that this is a chronic disease that needs consistent treatment. Your doctor will work with you to create a long term strategy to keep your eyes as comfortable as possible.