How to Choose Artificial Tears

So your eye doctor has recommended that you apply artificial tears several times per day for your dry eye symptoms. If you've been in the eye care aisle at the drug store, you may be completely overwhelmed by the many eye drop choices. Which artificial tear should you try? What is the difference between different over-the-counter artificial tear drops?

Your tears play an important role in keeping you healthy. Tears keep the surface of your eyes clean and moist and help protect your eyes from debris and bacteria. Although they may appear to be nothing more than water, your tears are actually quite complex. They are composed of water, carbohydrates, lipids, electrolytes, lysozymes (enzymes that act like natural antibiotics to kill bacteria and viruses), lactoferrin (proteins that prevent or slow bacterial growth), binding proteins and vitamins. A model of the tear film that scientists have adopted is a basic three-layer film that consists of a mucus layer, water layer, and a lipid or oily layer.

Although it is impossible for over-the-counter artificial tears to substitute perfectly for natural tears, manufacturers of artificial tears try to simulate the natural tear film or at least one of the three layers to improve where natural tears are lacking. Because there are so many different brands of artificial tears, it's sometimes confusing to figure out which one is best for your eyes. Some artificial tears are thin, like water and some are thick, almost like a gel. Most artificial tears contain hydrogels or particles that work to increase the moisture in your eyes for a longer period of time. Some artificial tears may seem to work better for your eyes since some brands of artificial tears contain more hydrogels than others.

• Preservatives: Some artificial tears contain preservatives and some don't. While preservatives will not cause harm to most of us, people with severe dry eye syndrome that require frequent instillation of artificial tears can have a toxic or sensitivity reaction to them that can actually worsen their symptoms. A particularly well-known preservative called BAK or benzalkonium chloride should be avoided for particularly sensitive individuals.
• Tear Changing: Some artificial tears have ingredients that change the chemical make-up of your tears to decrease negative or pathological changes that can occur to your eye as a result of having dry eyes for a long period of time. One school of thought is that if you change the composition of the tear film, the symptoms of dry eye will be reduced. Artificial tears that decrease that change the composition of your tears include Optive, Hypotears, Akwa Tears and Thera Tears.
• Eye Coating: Some artificial tears have ingredients that promote healing of the surface cells of the eye. Artificial tears that contain HP-guar are much more likely to improve the moisture content of cells that have more damage due to dryness. HP-guar is a molecule that forms a gel layer that protects the damaged cells. This gel layer also increases the likelihood of the water component of your tears to "stick" to your eye. Artificial tears that work by coating the eye include Systane Ultra and BLINK Tears.
• Oil Stabilizing: Some artificial tears aim to stabilize the oil part of the tear film. The oil part of the tear film can be disrupted if conditions are present such as blepharitis or meibomian gland dysfunction. If the oil part of the tear layer is disrupted, your natural tears will evaporate at a much faster rate than normal, leaving your eyes feeling dry and gritty. These artificial tears actually contain oily ingredients such as castor oil or mineral oil. Examples of these artificial tears are Refresh Endura, Systane Balance, and Smooth XP artificial tears.

It is important for you to take a few moments to discuss with your eye doctor the origin of the dry eye condition you may have. Your doctor may recommend a specific artificial tear that may be a better alternative for the type and level of severity of your dry eye condition.