Dry eyes are caused by a lack of tears. Tears are necessary for the normal lubrication of your eyes and to wash away particles and foreign bodies.

If you have dry eyes, you will feel a burning, scratching, or stinging sensation. You may also have strained or tired eyes after reading, even for short periods of time. If you wear contacts, they will likely feel uncomfortable. Having dry eyes for a while can lead to tiny abrasions on the surface of your eyes.

Common causes of dry eyes include:

• Aging
• Dry environment or workplace (wind, air conditioning)
• Sun exposure
• Smoking or second-hand smoke exposure
• Cold or allergy medicines
• An eye injury or other problem with your eyes or eyelids (like a drooping eyelid or bulging eyes)
• Sjogren's syndrome -- includes dry eyes, mouth, and mucus membranes, and often rheumatoid arthritis or other joint disorder
• Previous eye surgery

The following steps may help:

• Try artificial tears, available as either drops or ointment. Ointments last longer, but are thicker and can cause blurry vision.
• Don't smoke. Avoid second-hand smoke, direct wind, and air conditioning.
• Use a humidifier, especially in the winter.
• Purposefully blink more often. Rest your eyes.

Call your doctor if:

• You have red or painful eyes.
• You have flaking, discharge, or a lesion on your eye or eyelid.
• You have had trauma to your eye, or you have a bulging eye or a drooping eyelid.
• You have joint pain, swelling, or stiffness.
• You also have a dry mouth.
• Your dry eyes do not respond to self-care measures within a few days.

Your doctor will take a medical history and perform a physical examination, including a careful eye examination.

To help better understand your dry eyes, your doctor may ask the following:

• How long have you had dry eyes? Does it involve one or both eyes?
• Do you have it all of the time or does it only occur at certain times, with certain activities, or in certain places?
• Does the dryness seem related to wind, dust, chemicals, sun, or light exposure?
• Does it affect your vision?
• Does it cause pain?
• Do your eyelids close easily?
• Have you noticed any drainage from your eyes?
• Does anything make your dry eyes worse?
• Does anything make your dry eyes better?
• Have you tried artificial tears? Do they help?
• Are you taking any medications? Which ones?
• Have you had surgery or an injury to your eyes or nose?
• Do you have allergies?
• Have you been using any new cosmetics?
• Do you have any other symptoms like dry mouth or joint discomfort?

Foulks GN. The evolving treatment of dry eye. Ophthalmol Clin North Am. 2003;16(1):29-35.

Mahoney EJ, Spiegel JH. Sj??gren's disease. Otolaryngol Clin North Am. 2003;36(4):733-745.