Overview

Dry eyes is a common condition that occurs when your tears aren't able to provide adequate lubrication for your eyes. Tears can be inadequate for many reasons. For example, dry eyes may occur if you don't produce enough tears or if you produce poor-quality tears.

Dry eyes feel uncomfortable. If you have dry eyes, your eyes may sting or burn. You may experience dry eyes in certain situations, such as on an airplane, in an air-conditioned room, while riding a bike or after looking at a computer screen for a few hours.

Treatments for dry eyes may make you more comfortable. These treatments can include lifestyle changes and eyedrops. You'll likely need to take these measures indefinitely to control the symptoms of dry eyes.

Source: http://www.mayoclinic.com

Symptoms

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
• Eye redness
• A sensation of having something in your eyes
• Difficulty wearing contact lenses
• Difficulty with nighttime driving
• Watery eyes, which is the body's response to the irritation of dry eyes
• Blurred vision or eye fatigue

When to see a doctor

See your doctor if you've had prolonged signs and symptoms of dry eyes, including red, irritated, tired or painful eyes. Your doctor can take steps to determine what's bothering your eyes or refer you to a specialist.

Source: http://www.mayoclinic.com

Causes

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. For others it's increased tear evaporation and an imbalance in the makeup of your tears.

Decreased tear production

Dry eyes can occur when you're unable to produce enough tears. The medical term for this condition is keratoconjunctivitis sicca(ker-uh-toe-kun-junk-tih-VY-tis SIK-uh). Common causes of decreased tear production include:

• Aging
• Certain medical conditions, including diabetes, rheumatoid arthritis, lupus, scleroderma, Sjogren's syndrome, thyroid disorders and vitamin A deficiency
• Certain medications, including antihistamines, decongestants, hormone replacement therapy, antidepressants, and drugs for high blood pressure, acne, birth control and Parkinson's disease
• Laser eye surgery, though symptoms of dry eyes related to this procedure are usually temporary
• Tear gland damage from inflammation or radiation

Increased tear evaporation

Common causes of increased tear evaporation include:

• Wind, smoke or dry air
• Blinking less often, which tends to occur when you're concentrating, for example, while reading, driving or working at a computer
• Eyelid problems, such as out-turning of the lids (ectropion) and in-turning of the lids (entropion)

Imbalance in tear composition

The tear film has three basic layers: oil, water and mucus. Problems with any of these layers can cause dry eyes. For example, the oil film produced by small glands on the edge of your eyelids (meibomian glands) might become clogged. Blocked meibomian glands are more common in people with inflammation along the edge of their eyelids (blepharitis), rosacea or other skin disorders.

Source: http://www.mayoclinic.com

Diagnosis

Tests and procedures that may be used to determine the cause of your dry eyes include:

• A comprehensive eye exam. An eye exam that includes a complete history of your overall health and your eye health can help your doctor diagnose the cause of your dry eyes.
• Measuring the volume of your tears. Your doctor may measure your tear production using the Schirmer test. In this test, blotting strips of paper are placed under your lower eyelids. After five minutes your doctor measures the amount of strip soaked by your tears.
• Determining the quality of your tears. Other tests use special dyes in eyedrops to determine the surface condition of your eyes. Your doctor looks for staining patterns on the corneas and measures how long it takes before your tears evaporate.

Source: http://www.mayoclinic.com

Complications

People who have dry eyes may experience these complications:

• Eye infections. Your tears protect the surface of your eyes from infection. Without adequate tears, you may have an increased risk of eye infection.
• Damage to the surface of your eyes. If left untreated, severe dry eyes may lead to eye inflammation, abrasion of the corneal surface, corneal ulcer and vision problems.
• Decreased quality of life. Dry eyes can make it difficult to perform everyday activities, such as reading.

Source: http://www.mayoclinic.com

Prevention

If you experience dry eyes, pay attention to the situations that are most likely to cause your symptoms. Then find ways to avoid those situations in order to prevent your dry eyes symptoms. For instance:

• Avoid air blowing in your eyes. Don't direct hair dryers, car heaters, air conditioners or fans toward your eyes.
• Add moisture to the air. In winter, a humidifier can add moisture to dry indoor air.
• Consider wearing wraparound sunglasses or other protective eyewear. Safety shields can be added to the tops and sides of eyeglasses to block wind and dry air. Ask about shields where you buy your eyeglasses.
• Take eye breaks during long tasks. If you're reading or doing another task that requires visual concentration, take periodic eye breaks. Close your eyes for a few minutes. Or blink repeatedly for a few seconds to help spread your tears evenly over your eyes.
• Be aware of your environment. The air at high altitudes, in desert areas and in airplanes can be extremely dry. When spending time in such an environment, it may be helpful to frequently close your eyes for a few minutes at a time to minimize evaporation of your tears.
• Position your computer screen below eye level. If your computer screen is above eye level, you'll open your eyes wider to view the screen. Position your computer screen below eye level so that you won't open your eyes as wide. This may help slow the evaporation of your tears between eye blinks.
• Stop smoking and avoid smoke. If you smoke, ask your doctor for help devising a quit-smoking strategy that's most likely to work for you. If you don't smoke, stay away from people who do. Smoke can worsen dry eyes symptoms.
• Use artificial tears regularly. If you have chronic dry eyes, use eyedrops even when your eyes feel fine to keep them well-lubricated.

Alternative medicine

Further study is needed, but some alternative medicine approaches may help relieve your dry eye symptoms. Discuss the benefits and risks with your doctor.

• Fatty acids. Adding omega-3 and omega-6 fatty acids to your diet may help relieve dry eye signs and symptoms. These are available as supplements and in foods such as flaxseed, salmon, sardines and vegetable oils.
• Castor oil eyedrops. These eyedrops may improve symptoms by reducing tear evaporation.
• Acupuncture. Some people have seen their dry eye symptoms improve after acupuncture therapy.

Source: http://www.mayoclinic.com

Lifestyle and home remedies

You may be able to manage your dry eyes with frequent eyelid washing and use of over-the-counter (OTC) eyedrops or other products that help lubricate your eyes. If your condition is long term (chronic), use eyedrops even when your eyes feel fine to keep them well-lubricated.

Selecting and using OTC products for dry eyes

A variety of nonprescription products for dry eyes are available, including eyedrops (artificial tears), gels, gel inserts and ointments. Talk with your doctor about which might be best for you.

Artificial tears may be all you need to control mild dry eye symptoms. Some people need to put drops in several times a day, and some use them only once a day.

Consider these factors when selecting an OTC product:

• Preservative vs. nonpreservative drops. Preservatives are added to some eyedrops to prolong shelf life. You can use eyedrops with preservatives up to four times a day. But using the preservative drops more often can cause eye irritation. Nonpreservative eyedrops come in packages that contain multiple single-use vials. After you use a vial, you throw it away. If you rely on eyedrops more than four times a day, nonpreservative drops are safe.
• Drops vs. ointments. Lubricating eye ointments coat your eyes, providing longer lasting relief from dry eyes. But these products are thicker than eyedrops and can cloud your vision. For this reason, ointments are best used just before bedtime. Eyedrops can be used at any time and won't interfere with your vision.
• Drops that reduce redness. It's best to avoid these as your solution for dry eyes, as prolonged use can cause irritation.

Washing your eyelids to control inflammation

For people with blepharitis and other conditions that cause eyelid inflammation that blocks the flow of oil to the eye, frequent and gentle eyelid washing may help. To wash your eyelids:

• Apply a warm washcloth to your eyes. Wet a clean cloth with warm water. Hold the cloth over your eyes for five minutes. Rewet the cloth with warm water when it cools. Gently rub the washcloth over your eyelids — including the base of the eyelashes — to loosen any debris.
• Use a mild soap on your eyelids. Use baby shampoo or another mild soap. Put the cleanser on your clean fingertips and gently massage your closed eyes near the base of your eyelashes. Rinse completely.

Your doctor may recommend that you do this daily, even when your dry eye symptoms have been relieved. Stopping this daily routine may allow your symptoms to return.

Source: http://www.mayoclinic.com

Risk factors

Factors that make it more likely that you'll experience dry eyes include:

• Being older than 50. Tear production tends to diminish as you get older. Dry eyes are common in people over 50.
• Being a woman. A lack of tears is more common in women, especially if they experience hormonal changes due to pregnancy, using birth control pills or menopause.
• Eating a diet that is low in vitamin A, which is found in liver, carrots and broccoli, or low in omega-3 fatty acids, which are found in fish, walnuts and vegetable oils
• Wearing contact lenses

Source: http://www.mayoclinic.com