Chronic dry eyes usually come down to one of two problems: your eyes aren’t producing enough tears, or your tears are evaporating too fast. The second cause is far more common, and it starts with tiny oil glands in your eyelids that aren’t working properly. Nearly 16 million Americans deal with dry eye disease, and women are affected at roughly two to three times the rate of men across all age groups. Understanding what’s driving your specific dryness is the key to actually fixing it.
The Oil Glands in Your Eyelids
Your tear film isn’t just water. It has an outer oily layer that acts like a lid, preventing the watery layer underneath from evaporating off the surface of your eye. That oil comes from dozens of tiny glands lining your upper and lower eyelids, called meibomian glands. When these glands get clogged or stop working well, the oil thickens, bacteria multiply inside the glands, and those bacteria release enzymes that make the oil even thicker. This creates a self-reinforcing cycle: thicker oil means less secretion onto your tear film, which means more evaporation, which means drier eyes.
This condition, meibomian gland dysfunction, is the single most common cause of chronic dry eye. You may notice it as a gritty, burning feeling that gets worse as the day goes on, or as eyes that water excessively (your eyes overproducing the watery component to compensate for the missing oil layer).
Screen Time Cuts Your Blink Rate Dramatically
Every time you blink, you spread a fresh layer of tears across your eyes. When you stare at a screen, your blink rate drops sharply. Research published in BMJ Open Ophthalmology found that people blink about 18 to 22 times per minute during relaxed conversation, but that number plummets to as few as 3.6 blinks per minute during computer use. That means your tear film sits exposed five to six times longer between refreshes, giving it far more time to evaporate.
If your dry eyes are worst at the end of a workday or after a long stretch of reading, screen-related blink suppression is likely a major contributor. Taking deliberate blink breaks every 20 minutes, or simply looking away from your screen at something distant, gives your tear film a chance to recover.
Medications That Dry Out Your Eyes
If you take any daily medications, they could be the reason your eyes feel permanently dry. Research from the Tear Film & Ocular Surface Society estimates that 62% of dry eye cases in older adults can be traced to systemic medications. The list is long and includes some of the most commonly prescribed drug classes:
- Antihistamines, which block the signals that trigger tear production along with allergy symptoms
- Antidepressants and antipsychotics, which affect the nervous system pathways that regulate moisture
- Blood pressure medications, including diuretics and vasodilators
- Anti-inflammatory painkillers like ibuprofen and aspirin
- Anti-anxiety medications, particularly benzodiazepines
Even eye drops prescribed for other conditions can make things worse. Up to 47% of people using glaucoma drops experience burning and dryness, largely because most formulations contain a preservative called benzalkonium chloride (BAK) that damages cells on the eye’s surface and triggers inflammation.
Autoimmune and Hormonal Causes
When dry eyes come paired with a persistently dry mouth, an autoimmune condition called Sjögren’s syndrome is worth considering. In Sjögren’s, the immune system attacks the glands that produce tears and saliva. Diagnosis typically involves blood tests looking for specific antibodies, a tear production test where a small strip of filter paper is placed under the lower eyelid to measure output, and sometimes a biopsy of tissue from the inner lip.
Hormonal shifts also play a significant role, which partly explains the gender gap in dry eye prevalence. Drops in estrogen and androgen levels during menopause reduce tear production and change tear composition. Pregnancy and hormonal contraceptives can trigger similar changes, though these are often temporary.
Other conditions linked to chronic dryness include thyroid disease, rheumatoid arthritis, lupus, and diabetes. If your dry eyes appeared alongside other symptoms like joint pain, fatigue, or skin changes, it’s worth investigating a systemic cause.
Your Environment Matters More Than You Think
Dry indoor air is one of the most overlooked triggers. Forced-air heating in winter and air conditioning in summer both strip moisture from indoor air, accelerating tear evaporation. The University of Rochester Medical Center recommends keeping indoor humidity at 45% or higher to protect your eyes. A simple hygrometer (available for a few dollars) can tell you where your home or office stands, and a humidifier can close the gap.
Wind, high altitude, and airplane cabins all compound the problem. If you notice your eyes are worse in specific environments, that’s a strong clue that evaporation is your primary issue rather than underproduction of tears.
What Actually Helps
The first step most people try is artificial tears, and they do help, but the type matters. Eye drops containing BAK as a preservative can worsen dryness over time, especially if you’re using them multiple times a day. The cumulative exposure to BAK correlates with worse ocular surface disease and lower quality of life. If you’re reaching for drops more than a couple of times daily, switching to preservative-free formulations is a straightforward improvement.
For oil gland dysfunction, warm compresses held against closed eyelids for 5 to 10 minutes can soften thickened oil and help the glands flow again. Gentle lid massage afterward pushes the loosened oil out. Doing this consistently, not just once, is what makes the difference.
Prescription Options
When over-the-counter drops aren’t enough, prescription treatments target the inflammation that drives chronic dry eye. The two main prescription drops work by calming the immune cells on the eye’s surface. One suppresses the proliferation of inflammatory cells directly; the other blocks those cells from binding to eye tissue and triggering a cascade of inflammation. Both take weeks to months before you notice improvement, which is why many people give up on them too early.
Omega-3 Supplements
You’ll find omega-3 fatty acids recommended in nearly every dry eye article online, but a large NIH-supported clinical trial found that patients taking 3,000 mg of omega-3 daily for 12 months did no better than those taking an olive oil placebo. The study specifically looked at moderate to severe dry eye and concluded that the evidence does not support omega-3 supplementation for this group. Eating fatty fish is good for plenty of reasons, but it may not rescue your tear film.
How Dry Eye Gets Diagnosed
If you’ve been dealing with constant dryness, an eye care provider can run a few quick, painless tests to measure what’s going on. The Schirmer test places a small paper strip under your lower eyelid for five minutes. Less than 10 millimeters of wetting suggests your eyes aren’t making enough tears. A tear breakup time test uses a drop of dye to watch how quickly your tear film falls apart between blinks. A normal tear film holds together for 8 to 10 seconds or longer. If yours breaks up in 2 to 3 seconds, that points to a compromised tear layer, often from oil gland problems.
These numbers help distinguish between the two main types of dry eye and guide treatment toward the actual problem rather than just masking symptoms with drops.