A blocked tear duct in dogs means tears can no longer drain from the inner corner of the eye down into the nose, so they spill over the lower lid instead. The usual signs are constant wetness below one eye, rust-coloured staining, and — if the trapped fluid gets infected — a sticky discharge that keeps coming back no matter how often it's wiped away. It is rarely an emergency, but it is one of the most common reasons an "eye infection" fails to clear, and it needs a veterinarian to find the cause. To put those observations in context, see Glaucoma in Dogs in the UK and Dog Corneal Ulcer for related questions about eye care and changes to watch for. For background that helps put eye care and changes to watch for in context, read Dog Pink Eye.
You can use Dog Ear and Eye Cleaners, Pekingese Dog Care and Dog Eye Wipes to look up the details that apply to your dog. For more detail on eye care and changes to look out for, start with Over-the-Counter Eye Drops for Dogs and Saline Solution for Dogs' Eyes.
This guide explains how the drainage system works, what blocks it, how vets confirm it, and what you can safely do at home while you wait for the appointment.
How your dog's tear drainage actually works
Tears are produced constantly by glands above the eye and inside the third eyelid. After washing across the eye's surface, they drain through two tiny openings on the inner edges of the upper and lower lids, called the puncta. From there, two short channels (the canaliculi) meet at a small reservoir, the lacrimal sac, which empties into the nasolacrimal duct — a narrow tube running through bone down to an opening inside the nostril (Merck Veterinary Manual, Hamor, 2023). See how blinking and tears protect a dog’s eyes for the details behind this part of the care plan. For a closer look at signs and observations relevant to eye care and changes to watch for, see Dog Eye Stye and Dog Third Eyelid Showing. If you want to explore the related questions about eye care and changes to watch for, start with Cloudy Dog Eyes.
That's why a dog with healthy drainage often has a slightly damp nose on the same side after you rinse the eye. When any point along that route is narrowed or plugged, tears back up and overflow the lid. The overflow itself is called epiphora. For interpreting what you see around the eye, see normal eye discharge and warning colors.
Signs of a blocked tear duct in dogs
- Wet fur under one eye, often worse after eating, exercise or wind.
- Reddish-brown tear staining along the inner corner — obvious on white and cream coats.
- Moist, irritated skin below the eye, sometimes with a yeasty smell.
- Recurring mucus or pus at the inner corner that returns within days of stopping antibiotic drops.
- A soft swelling just below the inner corner of the lower lid — a red flag for infection of the lacrimal sac.
One-sided signs point more strongly toward a drainage problem than toward allergies, which usually affect both eyes. If both eyes simply water, start with our guide to dog watery eyes, because the list of causes is broader. For a separate nutritional-support decision, compare eye supplements and what canine research supports rather than assuming an oral supplement replaces examination or eye treatment. Compare the current Pure Majesty Pets Advanced Vision label before adding a product in this category. For interpreting irritation rather than choosing a cleaner by appearance, see eye allergy versus infection signs. For a closer look at signs and observations relevant to eye care and changes to watch for, see Dog Squinting One Eye.
Read Angel Eyes for Dogs UK for more detail on eye care and changes to look out for. If you’re comparing approaches to eye care and changes to look out for, see Bacterial Eye Infection in a Dog and Red Eyes in Dogs.
What causes a blocked tear duct?
Born with it: imperforate or narrow puncta
Some puppies are born with a lower punctum that never opened. The Merck Veterinary Manual describes imperforate puncta as an infrequent but recognised cause of tearing in young dogs, corrected by surgically opening the membrane and keeping it open with a temporary catheter for several weeks while it heals. Cocker Spaniels, Poodles, Golden Retrievers, Bedlington Terriers and Samoyeds are the breeds most often mentioned.
Foreign bodies — especially grass awns
This is the cause owners rarely suspect. In a Leipzig University case series, 14 dogs with one-sided infection of the lacrimal sac had been treated unsuccessfully for one to eight months; when the sac was opened surgically, every dog had one or two plant fragments lodged inside, and the discharge cleared in all of them after removal (Steinmetz et al., 2022). A larger Spanish series of 28 dogs with foreign-body dacryocystitis used fine forceps passed through the upper punctum to extract the material without an incision in many cases (Jimenez-Ramos et al., 2024). If your dog runs through tall grass or fields — a routine late-summer walk in rural Ontario or on the Prairies — and one eye has had a stubborn discharge for weeks, mention it to your vet. If stiffness is limiting that activity, the joint supplement comparison can help you review a longer-term mobility plan after the cause has been assessed.
You can use How to Get Something Out of My Dog's Eye and Dog Eye Twitching to look up the details that apply to your dog. To compare the signs and questions to take into account, see Entropion in Dogs and Pannus in Dogs UK.
Infection and debris: dacryocystitis
Inflammation of the lacrimal sac, called dacryocystitis, is the classic "tear duct dog eye infection." It usually follows obstruction by inflammatory debris, a foreign body or a mass pressing on the duct. Merck notes it produces tearing, a conjunctivitis that doesn't respond to treatment, a painful swollen area under the inner corner in acute cases and, occasionally, a draining tract below the lower lid. Our guide to dog eye health describes the changes you can note for your vet.
For related questions about eye care and changes to look out for, read Cherry Eye in Dogs and Can Dogs See Color? What Blue, Yellow, Red and Green Look Like. Our guide Uveitis in Dogs UK covers a related part of eye care and changes to look out for.
Teeth, tumours and trauma
The nasolacrimal duct runs close to the roots of the upper teeth. Merck warns that dacryocystitis can be confused with infection of the upper carnassial tooth, and a published case describes duct obstruction caused by a tooth growing inside the nasal cavity (Voelter-Ratson et al., 2015). Nasal tumours, facial fractures and chronic rhinitis can also compress the duct, which is why older dogs with new one-sided tearing deserve a careful work-up. If you are comparing a food-added dental product as well, use the dental powder evidence guide to distinguish daily plaque care from treatment of established dental disease. For a specific label to review against those criteria, see Pure Majesty Pets Dog Dental Powder. See the difference between plaque and tartar for the details behind this part of the care plan. For a closer look at teeth and gum care, see our guide to dog food that cleans teeth. For questions about daily dental care, the guides Dog Toothpaste vs Dental Powder and Purpose Dental Powder Reviews cover separate parts of the topic.
Face shape
Flat-faced breeds (Shih Tzu, Pug, Pekingese, French Bulldog) often have tight lower lids that roll inward at the inner corner and cover the punctum, plus hair in that spot that wicks tears onto the face. It's a mechanical problem rather than a true blockage, but it looks identical at home. For a breed-specific example of the questions to consider, see Brachycephalic Dog Breeds and Teddy Bear Dog Breeds. For the related question of breed-specific care, see our guide to teddy bear dog breeds.
For more on the signs and questions to take into account, read Ectropion in Dogs and Cataracts in Dogs UK.
Blocked tear duct or something else? A quick comparison
| What you notice | More likely | What to do |
|---|---|---|
| One eye always wet, clear tears, dog comfortable | Blocked or narrowed duct, punctum problem | Book a routine vet visit |
| One eye, sticky yellow-green discharge that keeps returning | Dacryocystitis (often a foreign body) | Vet within a few days; ask about a duct flush — see dog green eye discharge |
| Swelling under the inner corner, tender to touch | Infected lacrimal sac or tooth-root abscess | Vet within 24 hours — see dog eye swollen |
| Squinting, eye held shut, cloudiness | Corneal ulcer, glaucoma, uveitis | Same-day vet — not a tear duct issue |
| Both eyes watering, itchy face and paws | Allergies | See warning signs of a dog eye infection to rule out infection |
How vets diagnose it
- Fluorescein passage test. A drop of orange dye goes in the eye. If it appears at the nostril within a few minutes, the duct is at least partly open. No dye does not prove a blockage — some normal dogs drain into the back of the throat — but it guides the next step.
- Nasolacrimal flush. With a fine cannula in the punctum, the vet gently pushes sterile saline through the duct. Resistance, or pus refluxing out of the other punctum, confirms the problem. Merck describes flushing as the standard first step to re-establish drainage, and it's often done under sedation.
- Imaging. If flushing fails or the problem returns, contrast X-rays or CT (dacryocystography) show where and why the duct is blocked.
Treatment options
- Flushing plus prescription drops — antibiotic or antibiotic-steroid drops chosen by your vet, sometimes guided by a culture of the flushed material.
- Opening an imperforate punctum, followed by a temporary stent.
- Foreign-body removal — by forceps through the punctum or a small incision into the sac (Steinmetz 2022; Jimenez-Ramos 2024).
- Temporary catheterisation with fine silicone tubing to hold a scarred duct open while it heals.
- Surgical bypass (conjunctivorhinostomy) when the duct is permanently damaged — a new channel drains tears into the nose or mouth.
- Treating the root cause — dental extraction, lid surgery for inward-rolling lids, or management of nasal disease.
What you can safely do at home
You can't unblock a tear duct at home, and you shouldn't try — massaging the corner or poking the punctum can push debris deeper and injure the lid. What you can do is keep the overflow from causing a second problem: wet, stained skin that breeds bacteria and yeast. If ear care is part of the grooming routine too, the ear cleaner comparison helps you compare products without choosing solely by scent or front-label claims. When comparing choices for ear care and changes to watch for, read Dog Ear Cleaners UK alongside the product details above. For two more perspectives on yeast-related skin and paw care, read Dog Ear Yeast Infection Treatment UK and Dog Ear Yeast Infection Treatment.
For related questions about ear care, read Dog Ear Infection Treatment, Home Remedies for Dog Ear Infection and Best Dog Ear Infection Treatment 2026.
- Wipe the inner corner once or twice a day with a clean cotton pad, from nose outward.
- Keep facial hair trimmed short at the inner corner (a groomer can do this safely).
- Dry the fold under the eye fully after every clean.
- Never use human redness-relief drops (Visine-type products contain decongestants that are toxic to dogs) or anything containing peroxide, bleach or alcohol.
For the daily clean itself, we formulated our gentle daily dog eye drops specifically for eyes that are already irritated. Here is what's in the bottle, with the numbers, so you can compare:
If you’re comparing approaches to eye care and changes to look out for, see How to Clean Around a Dog's Eyes and Optixcare Eye Lube for Dogs.
| Feature | Typical drugstore tear-stain cleaner | Pure Majesty Pets eye drops |
|---|---|---|
| pH | Often unstated | 7.0–7.2, matched to natural tears |
| Grade | Cosmetic | Ophthalmic-grade, 10-micron sterile-filtered |
| Moisturising active | Usually none | Sodium hyaluronate 0.05% |
| Soothing botanicals | Rarely listed with amounts | Aloe vera 8%, chamomile 2%, pro-vitamin B5 |
| Stain control | Peroxide or bleach in some | Sodium phytate 0.15%, a gentle mineral chelator |
| Alcohol / fragrance | Common | None |
To be clear about limits: these are non-medicated hygiene drops. They won't open a blocked duct, treat dacryocystitis or replace the antibiotics your vet prescribes. They're the comfortable daily clean-up alongside that treatment — and, for dogs whose tearing is permanent, the part of the routine that keeps staining and skin irritation under control. Made in Canada, with free worldwide shipping. For more options, browse our dog eye care essentials, or read our tear stain remover guide if staining is your main concern. For routine debris around an otherwise comfortable eye, compare eye cleaners for routine debris and tear stains; this is a different task from treating a painful or inflamed eye.
Common mistakes owners make
- Restarting the same antibiotic drops for months. If discharge returns every time drops stop, the source is often inside the duct — ask for a flush.
- Assuming tear stains are only cosmetic. New staining on one side in an adult dog is a symptom worth a look.
- Waiting on a swelling under the eye. A tender lump below the inner corner can be an abscess and needs prompt care.
Frequently asked questions
Can a blocked tear duct in dogs clear up on its own?
Mild blockages from debris sometimes clear after an infection settles, but congenital problems, foreign bodies and scarring do not. If tearing persists beyond two weeks, have your vet check the duct.
Is a blocked tear duct painful for dogs?
Simple overflow usually isn't. Infection of the lacrimal sac can be painful, especially when there is swelling under the inner corner of the eye. For the tear-production side of eye comfort, read dry eye and tear production.
Can I flush my dog's tear duct at home?
No. Flushing the duct requires a sterile cannula placed in the punctum, usually with sedation. At home, limit care to rinsing the eye surface and cleaning the skin around it.
Our guide Dog Eye Cleaner covers a related part of eye care and changes to look out for.
Does a tear duct problem cause tear stains?
Yes. When tears can't drain, they sit on the fur, where pigments called porphyrins and minerals discolour it reddish-brown. Treating the drainage issue is the real fix; daily cleaning keeps the skin healthy meanwhile.
If you want to look at the options in more detail, start with Subconjunctival Haemorrhage in Dogs.
For an evidence-based overview of eye-support products, label checks and limits, see our UK guide to eye supplements for dogs.
For related UK yeast-care guidance, read dog yeast infection medicine and dog paw yeast infection.
For related UK yeast-care guidance, compare dog yeast infection home remedies and dog yeast infection treatment in the UK.
For diet and gut-support options that can influence product choice, see dog food for allergies and yeast infections and probiotics for dogs with yeast and allergies.
Scientific References
- Steinmetz A, Jara Dohmann GW, Blobner CC. Dacryocystitis in dogs caused by foreign bodies — Diagnosis and therapy in 14 cases. Veterinary Ophthalmology. 2022;25(2):180-185. PMID 34984785
- Jimenez-Ramos L, Ripolles-Garcia A, Caro-Suarez M, et al. Nasolacrimal sac foreign body extraction using vitreoretinal forceps in 28 dogs. Veterinary Ophthalmology. 2024;27(6):510-521. PMID 38414137
- Voelter-Ratson K, et al. Dacryocystitis following a nasolacrimal duct obstruction caused by an ectopic intranasal tooth in a dog. Veterinary Ophthalmology. 2015. PMID 25312093
- Hamor RE. Nasolacrimal and Lacrimal Apparatus in Animals. Merck Veterinary Manual. 2023. merckvetmanual.com
Veterinary disclaimer: This article is educational and is not a substitute for veterinary diagnosis or treatment. A suspected blocked tear duct should be examined by a licensed veterinarian in Canada or the US. Pure Majesty Pets eye drops are non-medicated hygiene products; they do not diagnose, treat, cure or prevent disease and have not been evaluated by Health Canada or the FDA as drugs. Free worldwide shipping.