The pesky brown streaks creeping down from their dog’s inner eye corners drive pet owners everywhere crazy – but what are they? Why does it make your dog look like they are crying? This is one of the most common questions I answer from pet parents as a veterinarian.
What is tear staining and why does it occur?
Tear staining refers to the browning of hairs near the inner corner of the eye. We see tear staining most often in white and light-colored dogs. Most of the time tear staining is normal and not of concern.
Tear staining occurs when a chemical called porphyrin, a breakdown product of blood in the tears, interacts with the light and is oxidized. This causes a brownish stain of the hair at the inner aspect of the eye.
What is the significance of tear staining?
Most often this is nothing more than a cosmetic problem. When there is a real medical problem involved, it often leads to excess tears and excessive tear staining. Medical problems that would cause excessive tearing, such as epiphora, include having:
A foreign object in the eye
A scratch or lesion on the eyeball itself (corneal ulceration)
A hair growing inward towards the eye and irritating it.
While tear staining is typically a non-medical issue, other eye problems can have very serious causes and consequences. Here are some signs that you should keep an eye out for:
Discharge and crust collecting at the eyes. A little daily accumulation is normal, but a change in the amount is a sign that something abnormal may be brewing.
Lack of or excessive tearing
Red or white eyelid linings (they should be pink)
Closed eyes or sensitivity to light
Cloudiness or change in eye color or color of the whites of the eye
Unequal pupil sizes
A visible third eyelid popping out towards the bottom of the eye (called a “cherry eye”)
Bulging of the eye
How do you keep your pet’s eyes healthy?
Take a step back daily and make sure your pet’s eyes are nice, bright, and glossy.
Keep the hair around the eyes trimmed back! Hair is a breeding ground for bacteria and is painful and irritating when lost in the eye.
Remember not to let your dog or cat ride in the car with its head out the window. Foreign substances can easily lodge in your pet’s eyes and cause injury or infection.
Is there treatment for tear staining?
If there is no medical reason behind your dogs tear stains, there is no treatment available. You may have heard of these products or even purchased them: Angel Eyes, Tear Stain Away, Pet Spark, etc. Over-the-counter medications aimed at treating tear staining are a dime a dozen. These products contain the antibiotic tylosin. The problem with this is two-fold.
Non-descript Drug Labels
The first issue is that the exact amount of antibiotic in the product is not specified on the label, which means your dog is ingesting an unknown amount of the drug every day. Obviously, if you’re going to use a drug, you should at the very least know how much is being used. An alternative to these is an accurately dosed capsule, which can be fulfilled by a compounding pharmacy with a prescription from your veterinarian - if it is medically warranted.
Cosmetic Medications vs Necessity
The second problem with these OTC tear-staining medications is the central issue itself: is it even appropriate to use an antibiotic daily for a cosmetic problem? Overuse of antibiotics is responsible for antibiotic resistance of bacteria in the environment and, in general, bacteria that becomes resistant to tylosin also becomes resistant to other bigger antibiotics.
With the overwhelming majority of tear-staining cases being simply a cosmetic issue, perhaps non-antibiotic treatment could be used instead, though it is admittedly less effective. The simplest treatment: gentle daily washing of this area of your pet’s fur. All you need is warm water and a paper towel, cotton ball, or washcloth.
All in all, the overuse of unnecessary medications is bad for everyone even if it doesn’t immediately impact your pet. If your dog seems to have excessive tear staining, talk to a vet to ensure there is no medical cause.