Tear Staining In Dogs – Causes And Treatments Explored
Do you struggle to keep your poodle-mix’s face clean of rusty streaks?
Despite your best efforts those rust-brown stains tracking down his face just won’t budge. Although it doesn’t bother the dog it upsets you that he doesn’t look his best. Whilst there’s no miracle answer to eliminating tear staining, this article helps you understand why it happens and what you can do about tear staining in dogs.
What Causes Tear Staining In Dogs?
Tears are vital to eye health; they keep the cornea moist and wash away dust. In a miniature marvel of biological engineering, the eye has a beautifully balanced mechanism whereby the tears produced drain away via the tear ducts, without spilling over the face.
- Think of this mechanism as a faucet and a sink. The faucet is left running, but the plughole is clear so the water drains seamlessly away.
For tear staining to happen there must be an imbalance in this system. Using the analogy above, the sink will overflow if either the faucets are fully turned on or the plug hole is blocked. For our dog, this means he either produces excessive amounts of tears or has blocked tear ducts.
Here are some of the physical factors that make tear overflow (and therefore staining) more likely.
Narrow Tear Ducts: Each eye has two tiny puncta (plugholes!) in the inner corner, one on the top lid and one on the bottom. These join together in a ‘Y’ junction to form one wider duct. Anything which narrows the puncta or ducts makes it more difficult for tear fluid to drain. The most common reasons include:
Blocked Tear Ducts: Due to debris or inflammation.
Impunctate Ducts: This is a recognized problem for poodles and is where the puncta are sealed over (like leaving the plug in the sink).
Micropuncta: This is a Cocker spaniel specialty (Cockapoo anyone?) where the tear ducts don’t develop fully and are unusually narrow.
Large Eyes: : Huge puppy dog eyes tend to roll the eyelids outward slightly, which also tips the tear duct away from the cornea making drainage less effective.
Increased Tear Production: Alternatively, the tear ducts may work fine but are overwhelmed by an excessive volume of tear fluid which spills over the face (epiphora). This can happen because:
Allergic Reaction: Air-borne irritants such as air fresheners, hairspray, perfume, or deodorant are frequent offenders.
Wind Chill: Ever had your eyes water in cold weather?
Physical Irritation: Grit in the eye or long hair rubbing on the cornea will cause epiphora.
In Turned Eyelids: When the eyelid scrolls inwards then with every blink the eyelashes rub on the cornea, which triggers watering.
Why Does Tear Staining In Dogs Happen?
Wait a minute! You say. Tears are colorless, so why does the rust-staining happen?
Great question and the answer is to do with natural chemicals in the tear fluid, called porphyrins.
When exposed to air, porphyrins oxidize. An example of oxidation in action is when you cut an apple in half, after a few hours the cut surfaces go brown: The same thing happens with tear fluid. That brown tear fluid is a dye that discolors the tissue it touches, turning hair that characteristic rust-brown.
How To Prevent Tear Staining
First, let’s bust a few myths.
Hypoallergenic Diets: MYTH: Some people recommend feeding a hypoallergenic diet or a gluten-free diet to a dog with excessive tear staining
BUSTED: There’s no logic to this argument. Food allergies in dogs manifest as extreme itchiness or an upset tummy and NOT excessive tear production. Fair enough, an allergen in the air (such as a pollen or aerosol spray) will cause physical irritation of the cornea; there is no proven link between epiphora and food.
Whitening Wipes: MYTH: The best way to remove tear stains is with a commercial tear whitener.
BUSTED: This is a little more complicated because although whitening solutions can work, they mainly rely on bleach-like chemicals which could irritate the eye. Thus, you may solve a cosmetic problem but cause more serious damage to the eye as a consequence.
In addition, any cleansing solution (especially the home-made variety) can harbor bacteria. Again, there’s a risk of wiping the eye with a bacteria-rich soup and causing an eye infection.
Antibiotics: MYTH: Certain antibiotics, such as tylosin, can help reduce tear staining.
BUSTED: The staining is down to porphyrins rather than infection, so it is an unwise use of antibiotics which could result in antibiotic resistance. If conjunctivitis is present, then a topical antibiotic eye ointment is the best option.
Indeed, some commercial stain removers contain tylosin in topical form (on the basis that there’s a yeast infection present.) However, because of the risk of antibiotic resistance, the FDA has withdrawn these products.
So that’s what NOT to do, let’s be more positive and see how you CAN make a difference.
Regularly Wipe the Eyes: Use a cotton wool ball (a fresh one for each eye) soaked in boiled water, and wipe those eye boogers away the moment you see them. Tear staining takes a few hours to happen (think of the cut apple) and so removing the tears promptly helps prevent staining.
Trim Hair from around the Eyes: Hair wicks moisture away from the eye, thus spreading the tear staining. Keep this area well-trimmed and the problem is easier to manage.
Avoid Irritants: Don’t smoke around the dog, and don’t let the dog in a room where aerosols have recently been sprayed…and yes this does include perfume, deodorant, and hairspray.
Use a Barrier such as Vaseline: In cold weather when eyes water more heavily, smear a fine layer of Vaseline over the skin beneath the eye. This prevents chapping and sore skin.
Use Malacetic Wipes: : If you suspect the dog has a yeast infection because of the constant wetness on their face, then speak to your vet about supplying malacetic wipes. These are a wet wipe impregnated with an anti-yeast ingredient which is related to vinegar.
Address Underlying Issues
Have a vet examine the dog’s eyes for anatomical problems such as in-turned eyelids or stray hairs rubbing on the cornea. In extreme cases, surgical correction of the eyelid’s position could drastically improve the problem.
The vet can use a special dye, fluorescein, to check how well the tear ducts work. [%] If a blockage is diagnosed, then flushing the tear ducts to dislodge the debris can help. However, micropuncta are trickier, since forcibly widening the ducts often leads to scar tissue formation which then narrows them again.
Also, a normal discharge from the eye is usually clear or rust-colored. If your poodle has a thick yellow-green or an unusually tacky discharge, these can be signs of infection or dry eye. Both of these need veterinary attention.
It’s All In The Genes!
And finally, poodle-mixes often suffer from tear-staining, thanks to their poodle ancestry. If the cause is down to anatomy and narrow tear ducts, then your best option is to get into the habit of wiping the dog’s eyes, as often as you can. Simple as that!
Nasolacrimal and Lacrimal Apparatus. Merck Veterinary Manual
Eye discharge or epiphora in dogs. VCA Hospitals
The Hidden Message Behind your Pet’s Tear Staining. Mercola Healthy Pets
Dr Pippa Elliott BVMS MRCVS
Dr. Pippa graduated as a veterinarian from Glasgow University in 1987. Since then she has worked in companion animal practice and has a special interest in internal medicine. Pippa is housekeeping staff to a naughty puggle, three cats, and a bearded dragon.