Eyes & Vision
Blocked Tear Ducts: When the Overflow Pipe Fails
The weepy eye that never quite stops: plumbing, staining and the fix.
Last reviewed
The weepy eye that never quite stops: plumbing, staining and the fix.
Last reviewed
Eyes run a constant production line of tears, and healthy plumbing drains them away invisibly: tiny openings at the inner corner of each eye collect the flow and pipe it down through narrow ducts into the nose, which is why crying humans sniff. When those ducts narrow or block, production continues, drainage fails, and the overflow runs down the face instead.
That overflow, the constantly wet inner corner and damp cheek fur, is the condition’s signature, and its medical name is epiphora. The eye itself is often perfectly comfortable; it is the drainage, not the eye, that is broken.
Some cats are simply built with narrow or kinked ducts from birth, and flat faced breeds carry the highest rates because compressed facial anatomy squeezes the plumbing. Acquired blockages join the list: scarring left behind by kittenhood cat flu, the swelling of infections and conjunctivitis pressing ducts shut, debris lodging in the channel, and occasionally a tooth root problem or growth pressing from nearby.
The history usually points at the cause: lifelong weeping suggests architecture, weeping that arrived after a snuffly episode suggests scarring, and sudden onset in one eye of an older cat earns the most careful look of all.
Overflow tears leave a signature worth reading: clear watering that dries into reddish brown tear staining on pale fur, a cosmetic pigment effect of normal tears, is the classic blocked duct picture. Colour changes the story: yellow or green discharge means infection or inflammation, not plain plumbing, and belongs on the conjunctivitis page and at the vet.
The other deciders are comfort and symmetry: a comfortable, open, quiet eye that merely overflows is drainage; squinting, redness or pain reroutes you to the ulcer and injury guides today. Wet is a plumbing question; sore is an eye question.
Confirmation is neat: a drop of the same fluorescein dye used for ulcers is placed in the eye, and in a working system the dye reappears at the nostril within a few minutes, having ridden the plumbing down. No dye at the nose, with an otherwise healthy eye, points squarely at the ducts.
The vet will also rule out the impostors, the eyelash or lid conformation rubbing tears into overproduction, early conjunctivitis, and in older cats the rarer pressing causes, because unblocking a duct achieves little if something else is filling the sink faster than any drain could cope.
The definitive treatment is a duct flush under anaesthetic or sedation: a fine cannula introduced into the duct opening and sterile fluid pushed through to clear debris and open the channel, often curing acquired blockages in one session, with antibiotic or anti inflammatory drops afterwards where infection or swelling played a part.
Congenitally narrow plumbing is less obliging: flushing helps some, others resume overflowing, and for a comfortable eye that simply waters, many owners and vets settle on managed acceptance rather than repeated procedures. Persistent problem cases can be referred for imaging and specialist options, but most of this condition’s story is far gentler than that.
For the cats whose ducts stay lazy, management is a face care habit: the inner corners wiped once or twice daily with a separate damp cotton pad per eye, always wiping away from the eye, the cheek fur kept dry enough that the skin beneath never stays damp, because chronically wet skin invites soreness and infection.
Watch for the change notes, staining turning to colour, comfort turning to squint, smell or soreness arriving, and report them rather than absorbing them into the routine. A blocked duct managed well is a cosmetic quirk with a flannel; the routine exists to keep it exactly that.
When the weeping has been there from kittenhood, architecture is the usual author: ducts born narrow, kinked or incompletely formed, often showing as twin damp tracks on a face that is otherwise perfectly happy. These cats frequently grow into their plumbing somewhat, and many settle into the mild, managed pattern this guide describes.
Weeping that arrives new in an adult reads differently and deserves more curiosity: scarring after an infection, swelling pressing the channel shut, debris, or in older cats something growing where nothing should. New onset on one side in a mature cat is the version that earns the promptest appointment on this page.
Tear ducts run a winding course from the eye’s inner corner down through the bones of the face to the nose, and the flatter the face, the more compressed and contorted that journey becomes. It is why the shortest muzzled breeds weep most, and why a Ragdoll’s moderate, balanced face keeps the breed at the luckier end of the table.
The same anatomy lesson explains the pattern within any breed: individuals with rounder eyes, shallower stops or tighter inner corners drain less efficiently than their siblings. Plumbing is inherited, which is one more quiet argument for meeting a kitten’s parents.
From the owner’s side, a duct flush is a day procedure: food withheld as instructed, a drop off, a phone call, a slightly groggy cat home by evening with instructions and sometimes drops. From the cat’s side it is a nap: the flush itself happens under sedation or anaesthetic precisely so that a fine cannula and a syringe of saline can do delicate work on a perfectly still patient.
Recovery is usually unremarkable, with the main aftercare being the drops given as prescribed and a few days of watching the corner that used to overflow. Many owners report the strangest part is the silence: a dry cheek after years of the drip.
Long facial fur wicks tears down the cheek like a lamp wick, spreading the damp and the staining far beyond the eye corner. Keeping that fur short, a careful trim by a groomer rather than home scissors near an eye, dramatically reduces the wet area, the staining and the risk of the skin beneath ever getting sore.
Pair the trim with the routine this guide teaches, wiping then drying, because damp fur is the whole problem in miniature. A tidy face and a dry cheek turn a lifelong condition into a barely noticeable habit.
A weepy but comfortable eye usually means the drain, not the eye itself: blocked tear ducts let normal tears overflow down the face. Flat faced anatomy, old flu scarring and simple debris are the usual causes. The vet confirms it with a dye test and can flush the duct under sedation, though some cats simply live with a managed drip and daily face wiping. The rule that matters: overflow without pain is this page, while squinting, redness or pain is a same day appointment.
Usually not: the classic case is a comfortable eye that simply overflows. Discomfort, squinting or redness means something more than plumbing is going on, and moves you to the sore eye pages and a same day call.
Acquired blockages often stay fixed after one flush; congenitally narrow ducts are less obliging and may resume overflowing. Your vet will tell you which story yours is likely to be, and a comfortable eye that drips is livable either way.
No: tear staining is a pigment effect of normal tears on pale fur, cosmetic rather than dangerous. The daily wipe exists to keep the skin beneath dry and comfortable, not because the stain itself does harm.
No. Human drops range from useless to actively harmful in feline eyes, and nothing should go into a cat’s eye without a current veterinary instruction for that cat. The safe home contribution is the gentle daily face care this guide describes.
Allergy tends to itch and redden rather than simply overflow, and it usually troubles both eyes along with skin or ears. A single quietly dripping eye is nearly always plumbing; an itchy face is a different conversation for the vet.
Weepy but comfortable is this page; sore or squinting is the corneal ulcer and eye injury pages, today. The conjunctivitis guide covers the infected middle ground.
For tear duct and eye anatomy detail, Cornell Feline Health Center covers feline ophthalmology clinically, and International Cat Care keeps owner friendly eye guides.