Your eyes feel dry because your tear film isn’t doing its job. That film is a thin, three-layered coating that keeps your eyes moist, clear, and comfortable. When any part of it breaks down, whether from too little tear production, too-fast evaporation, or both, you get that gritty, stinging, tired-eye feeling. The causes range from staring at a screen too long to hormonal changes to medications you might not suspect.
How Your Tear Film Breaks Down
Your tears aren’t just saltwater. They’re a structured mix of three layers: an oily outer layer that prevents evaporation, a watery middle layer that hydrates and nourishes, and a mucus inner layer that helps tears stick to the eye’s surface. Dry eye falls into two broad categories depending on which part fails.
The more common type is evaporative dry eye, driven by problems with tiny oil-producing glands along your eyelid margins called meibomian glands. When these glands become blocked or inflamed, they stop releasing enough oil. Without that protective outer layer, your tears evaporate too quickly. The glands can become obstructed as they thicken with age, from chronic lid inflammation, or from reduced hormone levels. Over time, the inflammation from unstable tears actually damages the glands further, creating a self-reinforcing cycle.
The other type, aqueous deficiency, means your lacrimal glands simply aren’t producing enough of the watery component. This can happen with aging, but it sometimes signals an autoimmune condition. About 1 in 10 people with clinically significant dry eye turn out to have Sjögren’s disease, an autoimmune disorder that attacks moisture-producing glands throughout the body.
Screens Cut Your Blink Rate in Half
If your eyes feel worst after hours on a computer or phone, there’s a straightforward explanation. You normally blink about 15 times per minute, but that rate drops by roughly half when you’re focused on a screen or other close-up task like reading. Each blink spreads a fresh layer of tears across your eye. Fewer blinks means your tear film sits exposed longer and dries out between refreshes.
This isn’t a sign of disease. It’s a mechanical problem. The 20-20-20 rule helps: every 20 minutes, look at something 20 feet away for 20 seconds. This interrupts your fixed gaze and prompts natural blinking. Positioning your screen slightly below eye level also helps, because looking downward narrows the exposed surface area of your eye, slowing evaporation.
Medications That Dry Your Eyes
In older adults, an estimated 62% of dry eye cases can be traced to systemic medications. The list is long: antihistamines, antidepressants, blood pressure drugs, diuretics, anti-anxiety medications, NSAIDs like ibuprofen, and heartburn drugs all make the cut. Many of these share a common mechanism. They have anticholinergic activity, meaning they interfere with the chemical signaling your glands rely on to secrete tears, mucus, and oil.
Some medications cause dryness through a different route entirely. Drugs like ibuprofen, aspirin, and certain heart rhythm medications can actually form tiny crystals in your tear film, physically disrupting it. If your eyes started feeling dry around the time you began a new medication, that connection is worth exploring with the prescriber. Stopping or switching the drug often resolves the problem.
Hormones and Dry Eye After Menopause
Women develop dry eye at significantly higher rates than men, and the gap widens after menopause. Research has linked low levels of both estrogen and testosterone in postmenopausal women to severe evaporative dry eye. These hormones don’t just affect tear production. They also influence meibomian gland function, meaning hormone decline can hit both the watery and oily layers of the tear film simultaneously.
This helps explain why dry eye can seem to come out of nowhere in your 40s or 50s. It’s not just aging. It’s a specific hormonal shift affecting the glands responsible for keeping your eyes comfortable.
Contact Lenses and Dry Air
If you wear contact lenses, you’re in a high-risk group. Between 30% and 50% of the world’s 140 million contact lens wearers experience contact lens-induced dry eye. The lens sits on your cornea and disrupts the normal flow of tears, preventing adequate moisture from reaching the surface behind the lens. This accelerates evaporation and leaves the cornea exposed.
Your environment matters too. Air conditioning, forced-air heating, airplane cabins, and dry climates all pull moisture from your tear film faster than your glands can replace it. Indoor humidity of about 45% or higher is the threshold where your eyes are most comfortable. In winter, heated homes often drop well below that. A humidifier in the rooms where you spend the most time can make a noticeable difference, as can avoiding direct airflow from vents or fans hitting your face.
When Dry Eye Points to Something Bigger
Most dry eye is a nuisance, not a warning sign. But persistent, severe dryness, especially combined with a dry mouth, joint pain, or fatigue, can indicate Sjögren’s disease. In Sjögren’s, the immune system attacks the glands that produce tears and saliva, gradually destroying them. Diagnosis typically involves tear production tests, salivary gland evaluation, blood tests for specific antibodies, and sometimes a gland biopsy or ultrasound.
Sjögren’s is worth catching early because the inflammation is progressive. Left untreated, it can cause lasting damage to the eyes and other organs. If your dry eyes are accompanied by a persistently dry mouth or you feel like your dryness is disproportionate to any obvious cause, that combination warrants investigation.
What Actually Helps
Artificial tears are the first line of relief. If you’re using them more than four times a day, choose preservative-free formulations. The preservatives in standard bottles can irritate the eye surface with frequent use, making the problem worse over time. For evaporative dry eye specifically, look for drops labeled “lipid-based” or “for MGD,” which help replace the missing oil layer rather than just adding water.
Warm compresses held over closed eyes for 5 to 10 minutes can soften blocked oil in the meibomian glands and improve their output. Doing this daily, especially in the morning, helps restore the lipid layer over time. Gently massaging the eyelids afterward can encourage the softened oil to flow.
You may have heard that omega-3 supplements help dry eye. A large clinical trial funded by the National Eye Institute tested 3,000 mg of omega-3 daily for 12 months and found no significant benefit over a placebo. That doesn’t mean diet is irrelevant to eye health, but omega-3 supplements alone don’t appear to be the fix many people hope for.
For chronic dry eye driven by inflammation, prescription eye drops work by calming the immune response on the eye’s surface. The two main options target T-cells, a type of immune cell that perpetuates the inflammatory cycle on the cornea and conjunctiva. One blocks T-cell proliferation directly, while the other prevents inflammatory cells from binding to the eye’s surface tissue. Both take weeks to months to reach full effect, and initial stinging is common. Your eye doctor can determine whether your dry eye has an inflammatory component that would benefit from these treatments.
If your dryness is tied to screen use, the fix is behavioral. Conscious blinking exercises, regular screen breaks, and adjusting your workstation so you look slightly downward at your monitor all reduce tear evaporation without any drops at all.