Everyone once in a while, everyone's eyes feel kind of dry and itchy—possibly from allergies or a pesky seasonal cold, or a slightly scratched contact lens. But for millions of Americans with dry eye, those bothersome symptoms are aren't just something that come and go occasionally—they're a pretty permanent part of life.
Dry eye disease—sometimes known as dry eye syndrome or just dry eye—isn't just the occasional itchy eyeball, it's a chronic ocular disease that occurs when your eyes don't make enough tears, or don't make the right type of tears, to keep your eye properly lubricated, according to the American Academy of Ophthalmology (AAO). Research from the American Journal of Ophthalmology says an estimated 16 million Americans have been diagnosed with dry eye disease, though the actual number of people may be higher.
Because eyes can get irritated by all types of things, the only way to get a true diagnosis of dry eye disease is to be evaluated by an eye doctor. But there are some pretty noticeable signs of dry eye that can tip you off to make an appointment with an ophthalmologist. Here, experts weigh in on eight common dry eye symptoms to watch out for—and why your eyes can feel this way with the condition.
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8-Dry-Eye-Symptoms-You-Need-to-Know-GettyImages-659261936 is a common symptom of dry eye, one that typically comes and goes. Vision may clear in the morning, after a night of shuteye. But when dryness sets in during the day, so does foggy vision.
The tears the coat the front of your eye—a layer known as the eye's tear film—is at play here. This tear film is the first thing that light hits before it goes into your eye. When there's a disruption in this layer (which is what can happen with dry eye), your vision can get distorted, Tom Cruse, OD, optometrist with Insight Vision Group in Denver and site residency director for the Illinois College of Optometry, tells Health.
"When the tear film is robust and smooth, then you can see very well through it," Amy Lin, MD, associate professor of ophthalmology and visual sciences at the University of Utah Moran Eye Center in Salt Lake City, tells Health. "But if the tear film is kind of ratty and it's not covering the eye very well, then it's like ripples on the surface of a pond or a lake."
Swollen blood vessels on the white, outer layer of the eyeball can give eyes a crimson hue or make them look completely bloodshot. If you don't have an eye infection or allergies, it's a good bet they're red because your eyes are super dry.
That's because without proper lubrication—which can occur with dry eye—the act of blinking can cause your eyelids to rub against your cornea, the whiter part of your eye. If this rubbing happens often enough, it can irritate the cornea. Basically, "if you have lack of tears, then the cells on the surface of the eye cry out in pain because they're not being protected," Steven Maskin, MD, medical director of the Dry Eye and Cornea Treatment Center in Tampa, Florida, tells Health. "Chemicals are released that cause inflammation," and redness is a byproduct, he explained.
Redness and inflammation may be due to meibomian gland dysfunction, meaning the tiny oil glands lining the eyelids aren't producing or releasing sufficient lubrication.
This may sound counterintuitive, but increased tear production with dry eye is basically just your eye responding to something that's bugging them, like a lack of lubrication. When your cornea senses that it is not getting enough tears because of dry eye, it sends a signal to your tear glands to up production, says Dr. Cruse, in order to attempt to flush out whatever's causing the irritation. These glands do as they're told, but your eye can only hold so much liquid before it starts to spill over and run down your cheeks, Dr. Cruse explains.
Patients who complain of excessive tearing often have evaporative dry eye syndrome, Esen Akpek, M.D. professor of ophthalmology at the Johns Hopkins University School of Medicine's Wilmer Eye Institute, tells Health. When the eye's oil layer is inadequate, the tear layer quickly evaporates, causing excessive tearing.
Eye heaviness or fatigue
The most commonly described symptom of dry eye is the feeling of the eyes being tired or fatigued, Arti Shah, OD, fellow of the American Academy of Optometry and optometrist at Elander Eye Care in Santa Monica, tells Health.
Insufficient tear film can leave your eyes fatigued, "and your eyelids try to droop a little bit in order to protect the eye surface," says Dr. Akpek.
The heaviness may also be related to meibomian gland dysfunction. This occurs when oil-secreting glands in the lids fail to produce enough oil to keep the tear film moist, or the oil, called meibum, becomes too thick to do any good. The glands themselves can become clogged and crusted.
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Just as it can cause blurriness, a disruption in the eye's tear film can also cause sensitivity to light—that's because your tear film is the first thing light hits as it enters your eye. The tear film is supposed to be one smooth, even layer, but dry eye can sometimes cause it to be uneven and choppy—that's what causes the light sensitivity, says Dr. Shah.
This is technically known as photophobia, or extreme sensitivity to light, according to the Not A Dry Eye Foundation. It can be temporary or constant and occur in all types of light.
People with photophobia may squint or shut their eyes when exposed to light. The amount of discomfort may vary, too. Some people may experience extreme pain when nerve endings in the eye come in contact with light. Others may complain of light being too bright.
Light-sensitive cells in the retina, the layer of tissue lining the back of the eye, may be responsible for the discomfort, according to the North American Neuro-Ophthalmology Society. It's thought that these cells may have connections with the nerve that is responsible for relaying sensory information to the head and face.
When your tears fail to lubricate your eye as they should, it can lead to your eyes feeling sandy, scratchy, or gritty—kind of like something is stuck in there and constantly irritating it, per the AAO.
"The surface of your eye just literally dries out, the cells dry out and cause these micro-abrasions," says Dr. Lin. Fortunately, it doesn't necessarily cause permanent damage. "Those dry spots heal when the eyes are more moisturized," she added.
A lack of lubrication comes into play again here: Without a nice, smooth surface for eyelids to move across, you can experience trouble blinking your eyes, says Dr. Shah. Specifically, your upper and lower lids don't move as easily as they would with proper lubrication. Dr Shah says this is best explained with a water slide analogy: You can go down a dry water slide, but it'll be a pretty bumpy ride.
Trouble wearing contacts
Contact lens wearers sometimes feel the need to reduce the amount of time they use contacts or ditch the lenses altogether because their eyes become so uncomfortable. Roughly half of contact lens wearers report dry eye symptoms. Long-term contact use can lead to loss of sensation in the cornea, the eye's clear surface, Dr. Maskin explains. It's the same for patients who've undergone LASIK eye surgery or other corneal procedures.
"When the sensitivity of the cornea is altered, it can lead to reduction in tear secretion, decreased blink and dry eye," says Dr. Maskin.
Should you switch to wearing glasses? Maybe or maybe not. With proper diagnosis and management, many people can comfortably continue wearing contacts, according to a report in Review of Optometry.
Extra sensitivity to irritants
The eyes endure a litany of insults: wind, smoke, dry air, cleaning product fumes, you name it. An inadequate tear film on the eye exposes nerve endings to whatever wafts in their path.
According to the Not A Dry Eye Foundation, the cornea, or window of the eye, has 300 to 600 times more nerve endings than any other part of the body. "So imagine a pin prick in your finger, but the pin is 600 times wider."
Any enclosed space with forced vented air, like air conditioning in a home, office, or car, or even an indoor fan, can make dry eyes worse, Dr. Lin adds. There can also be eye sensitivity to fumes (even from foods while cooking) and perfumes, the foundation says.
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Stinging or burning eye pain
Eyes need adequate lubrication to feel comfortable, and blinking plays a crucial role. That's how meibum, the oily substance that keeps the eyes lubed up, is released. When people engage in activities requiring intense focus, they may not blink enough. Or they may not sufficiently close their eyes when they blink. That may be one reason dry eye patients experience a burning sensation in the eyes or on the eyelid margins.
"When you have tears that evaporate readily, it leaves the cornea desiccated, and that gives you a sense of burning," says Dr. Maskin.
Stringy mucus in the eye
Though this symptom is more common in individuals with moderate to severe dry eye and may occur in combination with other conditions, like an infection or allergy, it can show up in dry eye, as well.
Here's what happens: People who don't have a good, watery layer on the eye surface experience friction and strain when they blink. And that causes the tear film to secrete more mucus to make up for the missing layer of moisture. According to Dr. Akpek, it's a "compensation mechanism of the eye to overcome the lack of good volume."
Trouble is when people wipe their eyes to clear the mucus, it can cause further insult to the eye surface and trigger more inflammation, said Dr. Akpek—and so begins a vicious cycle.
Inability to cry
If you're feeling emotional, but the tears won't come, it could be a dry eye symptom. Keep in mind that reduced tear production may also result from any number of factors, from hormonal changes to medication side effects. It's also one of the hallmarks of Sjogren's syndrome, an autoimmune disorder that causes dry eye, mouth and vagina.
Staring at phones, computer screens, electronic devices, or even paper books for extended periods of time is not very conducive to maintaining moist eyes. When people are engaged in these activities, they tend blink at one-third of the normal rate, says Dr. Lin.
This can happen with driving too—any activity that requires intense focus, say, maneuvering a vehicle from point A to point B, tends to cause people not to blink as much as they normally would. With nighttime driving specifically, headlight and street light glare may also be extra bothersome, as can driving at night with eye fatigue.
To stave off dryness while reading or driving, follow this rule of thumb: Take a break every 20 minutes by looking 20 feet away for 20 seconds.
Although that may seem extreme, when dry eye symptoms become severe, they can completely overwhelm people and contribute to depression.
Dr. Maskin specifically says he has seen about two dozen patients who planned or tried suicide in his 25 years of practice. He urges people to be their own advocates for symptom relief.
"All bad dry eye starts out as annoying nuisance, or just minimal dry eye," he says. "If you let it build up over time, you become a significant risk factor for more significant dry eye."
If you experience any of the above symptoms, bring them up to your eye doctor, Dr. Shah advises. They can perform a variety of tests to determine if you are indeed suffering from dry eye, or if something else—like a problem with your eye muscle, for example—is causing your symptoms, and determine the best course of action to treat the condition. Definitely don't delay this visit, says Dr. Shah—getting your dry eye symptoms checked sooner rather than later can boost your quality of life and help prevent eye infections and damage to the cornea.
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