How to Prevent and Clean Dog Tear Stains

1 Preventing and Cleaning Dog Tear Stains

How do dog tear stains appear?

Before the causes, look at the eye structure: two parts matter, the tear gland and the nasolacrimal duct. The tear gland makes tears that moisten the eyeball, so a healthy eye looks dewy.

Tears then drain through the nasolacrimal duct into the nose, a balanced flow. When the balance breaks, say the gland inflames and overproduces, exceeding the duct’s capacity, tears spill from the eye corner and build into stains over time.

Some breeds form stains more easily by nature. Short-faced dogs have a duct that is born too curved and narrow, so tears often exceed capacity and most have stains; if a dog is ill and the duct blocks, tears flow from the corner and stain.

Tears are clear, so why are stains often deep red?

Because tears contain a substance called porphyrin.

Porphyrin is a natural waste from red-blood-cell breakdown, carrying iron.

In dogs, a good deal of porphyrin leaves through urine, tears, and saliva.

Anyone with basic chemistry knows iron oxidizes to brick red or deep red, the color of rust.

So brick-red stains are no mystery.

This also explains why some dogs have brick-red mouths, saliva carries porphyrin too.

What might cause tear stains?

Beyond the common causes above, these also commonly cause dark stains; owners can learn them to prevent stains in their dog.

Illness

1. Dacryoadenitis, inflamed tear glands

2. Nasolacrimal duct blockage

3. Ear infection

An ear infection can also irritate the sensitive tear gland, making it overproduce; the duct cannot cope and stains form.

4. Entropion

Inward-growing lashes keep irritating the eye corner, so the dog keeps tearing; excess tears cannot drain in time and stain.

5. Other eye diseases

Congenital factors

1. Special breeds

Short-faced dogs like Shih Tzu, Yorkie, French Bulldog;

Also dogs with thick fur around the eyes, like Pomeranian and Teddy.

Dense fur easily pokes the eye and triggers tearing.

2. Congenital defects

From genetics or birth, the gland is simply sensitive, or the duct is born narrow.

Like people, siblings from the same parents differ in many ways.

Environmental factors

1. Smoking at home.

Secondhand smoke and heavy fumes irritate the nose and make the dog uncomfortable, causing excess tears.

2. Pollen, dust, and other allergens

Your dog may be allergic to a pollen; when the season comes or you bring such flowers home, sudden stains may mean an allergy flared.

Food factors

This is why some owners ask: why did stains appear after switching food?

1. Food allergy

Allergy to an ingredient in kibble or homemade meals.

Common dog allergens are corn, wheat, and beef.

2. Too many low-quality ingredients in kibble

Poor, hard-to-digest food burdens the liver. This also explains why many dogs’ stains clear up after a food change or switching to homemade meals.

What can owners do?

Knowing the causes and triggers, owners just identify them and act accordingly.

Check the fur around the eyes often so it does not grow long into the eye;

Wipe the eye corner with a cotton ball dipped in citric acid or liquid vitamin C; it reacts with the iron in porphyrin so no brick-red mark forms.

Use pet tear-stain wipes, or a little petroleum jelly, to remove stains.