A tearing eye is almost always caused by one of two problems: your eye is making too many tears in response to irritation, or the drainage system that normally carries tears away is partially blocked. Sometimes both happen at once. Understanding which category your tearing falls into helps you figure out what to do about it.
Your tears are produced by a small, almond-sized gland tucked behind the upper outer corner of each eye. Oil glands along the edges of your eyelids add a thin layer of oil that keeps the watery tears from evaporating too quickly. When everything works properly, tears spread across your eye with each blink, then drain through tiny openings in the inner corners of your eyelids, traveling through a series of small tubes that empty into your nasal cavity. A problem at any point in this system can leave you with a watery, overflowing eye.
Dry Eyes Are the Most Common Culprit
This sounds like a contradiction, but dry eyes are one of the leading reasons for excessive tearing. When your eye’s surface doesn’t stay lubricated well enough, it becomes irritated. Your body responds by flooding the eye with a rush of watery tears. These reflex tears are thinner and less balanced than normal tears, so they don’t actually fix the dryness. They just overflow down your cheek, and the cycle repeats.
Dry eye tearing tends to be worse in specific situations: staring at a screen for long stretches, sitting in air conditioning or heated rooms, exposure to wind, or wearing contact lenses. If your eyes feel gritty, scratchy, or tired in addition to watering, dry eye is a strong possibility. Over-the-counter lubricating drops (often called artificial tears) can help break the irritation cycle by keeping the eye surface moist enough to prevent those reflex tear floods.
Allergies and Irritants
Allergic reactions in the eye produce watery, itchy tearing that typically affects both eyes at the same time. Pollen, pet dander, dust mites, and mold are the usual triggers. The hallmark sign that separates allergic tearing from other causes is itchiness. If your eyes itch intensely and you’re also dealing with sneezing or a stuffy nose, allergies are the likely driver.
Irritants work differently. Smoke, chemical fumes, onion vapors, and even strong perfumes trigger reflex tearing as a protective response. Your eye is essentially trying to wash the irritant away. This type of tearing stops once you remove yourself from the irritant. For allergy-related tearing, antihistamine eye drops (available over the counter under names like Zaditor or Alaway) block the immune response that causes the itching and watering in the first place.
Infections and Pink Eye
Viral and bacterial eye infections both cause tearing, but they look different. A viral infection (the most common type of pink eye) produces watery discharge along with redness and irritation. It often starts in one eye and spreads to the other within a few days. A bacterial infection, by contrast, produces thick yellow or green discharge rather than clear, watery tears. Both cause redness and discomfort, but the color and consistency of the discharge is the key difference.
Viral conjunctivitis typically resolves on its own within one to two weeks. Bacterial infections usually need antibiotic drops. If you’re producing colored, sticky discharge, especially if your eyelids are crusted shut in the morning, that points toward a bacterial cause worth getting treated.
Blocked Tear Ducts
When the drainage system is blocked, tears have nowhere to go. They pool in the eye and spill over the lid, even though the eye isn’t producing more tears than normal. Think of it like a clogged downspout on a house: the rain hasn’t changed, but the water backs up and overflows because it can’t drain.
Tears normally flow through tiny openings called puncta on the inner edge of each eyelid, then travel through narrow tubes into the nasal cavity (which is why your nose runs when you cry). A blockage anywhere along this path causes persistent tearing, usually in one eye. You might also notice mild swelling or tenderness near the inner corner of the eye, or recurrent infections in the tear duct area.
Blocked tear ducts are common in newborns and often resolve within the first year as the drainage system matures. In adults, blockages can develop from chronic sinus infections, nasal polyps, injury, or age-related narrowing of the ducts. When conservative measures like warm compresses and gentle massage don’t help, a surgical procedure to create a new drainage pathway has a success rate of about 85%.
Eyelid Problems
Your eyelids play a bigger role in tear management than you might expect. The oil glands lining the lid margins produce the oily outer layer of your tear film. When these glands become clogged or inflamed, a condition called blepharitis, the tear film destabilizes. Without enough oil, tears evaporate too fast, triggering the same irritation-and-reflex-tearing cycle that dry eye causes. Signs of blepharitis include red, swollen lid margins, flaky skin at the base of the lashes, and a gritty feeling. Keeping the lids clean with warm compresses and gentle lid scrubs helps the oil glands function normally again.
In older adults, the eyelid itself can shift position. Sometimes the lower lid turns inward, pushing the eyelashes against the surface of the eye. Misdirected lashes create constant friction that leads to pain, redness, a foreign body sensation, and heavy tearing. Left uncorrected, the chronic irritation can scratch the cornea. This type of tearing doesn’t respond to drops because the mechanical irritation continues with every blink. Correcting the eyelid position, usually with a minor procedure, resolves the tearing.
Environmental and Screen-Related Tearing
Wind, cold air, bright sunlight, and dry indoor environments all provoke reflex tearing. Your eyes respond to these conditions the same way they respond to any irritant: by producing a protective surge of tears. Wearing wraparound sunglasses outdoors can reduce wind and UV-triggered tearing significantly.
Screen use is a subtler trigger. People blink about 60% less often when staring at a phone, computer, or television. Fewer blinks mean the tear film breaks down faster between refreshes, the corneal surface dries out, and reflex tearing kicks in. If your eye waters mainly during or after extended screen time, deliberate blinking breaks every 20 minutes and lubricating drops can make a noticeable difference.
How to Tell What’s Causing Your Tearing
A few details can help you narrow down the cause before you ever see anyone about it:
- One eye or both? Allergies almost always affect both eyes. A blocked tear duct, infection, or eyelash problem usually starts in one.
- Itching? Strong itchiness points to allergies. Grittiness or burning points to dryness or blepharitis.
- Discharge color? Clear and watery suggests a viral infection, allergy, or irritation. Thick, yellow, or green discharge suggests a bacterial infection.
- When does it happen? Tearing mainly outdoors or in certain seasons suggests allergies or environmental triggers. Constant tearing regardless of setting points toward a blocked duct or eyelid issue.
- Swelling near the nose? Tenderness or puffiness at the inner corner of the eye, near the bridge of the nose, suggests a blocked or infected tear duct.
Most episodes of watery eyes resolve with simple measures: lubricating drops for dryness, antihistamine drops for allergies, warm compresses for clogged oil glands, or simply avoiding the irritant. Tearing that persists for more than a couple of weeks, keeps coming back, or comes with pain, vision changes, or colored discharge is worth having evaluated to rule out a structural problem or infection that needs specific treatment.