Dry Eyes — A Complicated but Treatable Problem

Most of us have experienced dry eye symptoms. Eyes get scratchy and red, vision may become blurry, it may be tiring to read. As we age, though, occasional bouts of dry eye symptoms can become more frequent, or even chronic. Dry eye disease affects around 1 in 5 older adults, so it's pretty common. Let's talk about why it happens and what you can do about it.

Why do eyes dry out?

You may be surprised to learn that tears aren't just salty water. They're an intricately balanced system of protection for the eye, and they have three distinct layers.

First, there's a layer of mucous (called the "mucin" layer). It helps the liquid stick to the eye and form a consistent film for protection. Mucin is made by cells inside the eyelid and on the white of the eye.

Then there's the watery part -- the part we think of as a tear. It's made up of water, salt, and other substances that help keep the eye clean and healthy. The watery part is produced by the lacrimal gland, which sits right above the eye.

On top of all that is an oily (lipid) layer, which keeps the watery portion from evaporating. This lipid layer is produced by glands located near the edges of the upper and lower eyelids. Interestingly, blinking is what causes the glands to secrete this important tear layer.

You can imagine that anything that disrupts this intricately balanced system can cause trouble. And it turns out that a malfunction in any of the tear-producing steps can a vicious cycle that's hard to stop.

When water in tears evaporates, it leaves behind the salt and other dissolved ingredients. With less water to dilute them, those substances are now more highly concentrated, and very irritating to the eye. And that irritation damages the eye's ability to produce both the mucin layer at the bottom of the tear and the lipid layer on top.  Now tears can't form a consistent film over the eye. At the same time water in the tear is even more likely to evaporate. And so the cycle of evaporation, irritation, and decreased mucin and lipid production goes on and on.

What can you do to minimize discomfort?

Start by looking at things that might be worsening your symptoms.

• Medications -- Quite a few medications (both prescription and nonprescription) can worsen eye dryness. Be sure to have your pharmacist look at your med list!

• Be intentional about blinking regularly -- Many things we do - driving and screen time among them - force us to keep our eyes open. But when we blink, we help our eyes produce the top layer of the tear.

• Think about your environment -- Fans, windy conditions, second-hand smoke, and dry indoor air quality can cause tears to evaporate more quickly.

• Treat blepharitis -- Blepharitis is an inflammation of the eyelids that can cause dry eye symptoms. Ask your doctor to take a look. It often responds well to regular eyelid cleaning.

• Try a warm compress --  Hold a clean, warm washcloth to your eyes for several minutes a couple of times each day. The warmth helps unclog the glands that secrete the oil your tears need.

Nonprescription treatments for symptoms of dry eye disease

There are dozens of nonprescription products you can use to put moisture back into your eyes. Eye drops, eye gels, and eye ointments are a great first step. They're all safe to be used as often as needed. Each product has its pros and cons, and none has been shown to be "the best". It's really all about what works for you.

Simple moisturizing eye drops, or "artificial tears", are made mostly of water. Inactive ingredients like buffers and electrolytes make them less irritating to the eye. Some contain  ingredients like hyaluronate or carboxymethylcellulose to make the solution stay on the eye longer. They tend not to blur vision, so are great for use at times you're doing things that require clear sight.

There are newer formulations that contain oils to more closely mimic the makeup of real tears. Research indicates they can limit water evaporation from the tear. Because they contain oils, they may cause blurred vision for a short time after use.

There are also gels. Gels are thicker than liquid drops, so they stay on the eye quite a bit longer than the more watery drops. These can cause blurred vision too, and it may last up to 15 minutes - a bit longer than the oil formulations. But they're safe to use during the day as long as you're careful.

Finally, ointments for the eye are intended to provide overnight moisture, and may be very helpful if you tend to wake up with dry, gritty eyes. Because they can blur vision for an extended period, it's best not to use them during the day.

Preservatives

Eyes don't have any defenses against infection, so anything used in the eye must be free from contamination. Preservatives are used in most eye products for that reason. But the preservatives can cause irritation with frequent use. Preservative-free products come in single-use vials that should be used only once then discarded  They're a little more difficult to use, and somewhat more expensive. But worth a try if you're concerned preservatives are causing trouble.

Dietary Supplements

Lots of dietary supplements are marketed for eye health. None of them have convincing evidence to show they improve symptoms of dry eye disease.

Keep your Vision Clear and Your Eyes Comfortable

There are plenty of products available without a prescription. Decide what kind of product you want to try, then read labels carefully. Learn how to introduce drops, gels, and ointments into your eye without contamination. And if you don't get relief from nonprescription products, don't despair. Talk with your eye doctor about prescription products that might help.

Please share your experiences, questions, and comments in the space below. Or contact us directly at Better My Meds. We love hearing from you!

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