The reddish-brown streaks beneath your dog's eyes are called tear stains — and they're caused by a pigment, not dirt. Here's what's actually going on and how to manage them safely.
What Actually Causes Tear Stains
Tears contain a compound called porphyrin — an iron-containing molecule that turns reddish-brown when exposed to air and light (oxidation). Porphyrins are excreted through tears, saliva, and urine. When tears overflow onto facial fur and sit there, the porphyrin oxidizes and leaves the characteristic rusty stain.
The root question is: why are tears overflowing in the first place? Common causes:
- Shallow eye sockets (brachycephalic breeds) — the anatomy simply doesn't allow full drainage
- Blocked or abnormally small tear ducts — the drainage channel is kinked or narrow
- Epiphora (excessive tearing) — abnormal tear production from allergies, eye irritation, or entropion (eyelid rolling in)
- Trichiasis — eyelashes that grow inward and irritate the eye surface, causing more tearing
- Yeast overgrowth — the Malassezia yeast thrives in the warm, moist stained area and darkens the stain further
- Diet and water — hard water high in minerals, certain food dyes, or food allergens can increase porphyrin levels in tears
Breeds Most Affected
Short-faced (brachycephalic) breeds are the most commonly affected: Maltese, Bichon Frise, Shih Tzu, Poodle, Lhasa Apso, Cavalier King Charles Spaniel, Pug, Bulldog, Chihuahua. Light-colored dogs show staining most visibly — a white Maltese with staining is striking; a black Poodle has the same staining but it's invisible against the coat.
How to Clean Tear Stains Safely
Regular cleaning prevents stain buildup and reduces yeast growth. Do this daily for heavily-stained dogs, 2–3 times per week for mild cases.
- Wipe the stained area with a soft cloth, cotton ball, or pet face wipe dampened with warm water or saline solution
- Work from the inner corner of the eye outward, following the hair direction
- For stubborn stains: apply a small amount of tear-stain-specific cleanser (see products below) to a cotton ball; gently work into the stained fur
- Dry the area thoroughly after cleaning — moisture encourages yeast growth
- Trim the stained fur short if the dog's breed allows — shorter fur = less surface area for staining and bacteria
Safe, vet-used products: Opti-Clear Eye Rinse (saline flush), Burt's Bees Eye Wash, Vetericyn Eye Wash. For established staining: Angels' Eyes powder (tylosin-based — check with vet first), TropiClean Spa Tear Stain Remover.
Prevention Strategies That Actually Help
- Daily face wiping — prevents stain buildup before it starts; the most effective intervention
- Filtered water — switching from tap water (high in minerals) to filtered or bottled water reduces porphyrin output in some dogs
- Limited ingredient or hypoallergenic food trial — if allergies are suspected, an 8-week food elimination trial sometimes dramatically reduces tearing
- Short face trim — keep fur around the eyes trimmed short to minimize fur wicking tears across the face
- Stainless steel or ceramic water bowls — plastic bowls can harbor bacteria that contribute to facial infections; replace with non-porous materials
- Probiotic supplement — some owners report reduced staining after adding a dog probiotic; the mechanism is unclear but it's low-risk to try
When Tear Staining Means a Vet Visit
See your vet if:
- Staining is sudden or dramatically worse than usual — may indicate a new eye condition
- The eye itself looks red, cloudy, squinting, or has discharge that isn't clear
- The dog is pawing at their eye or face
- Staining is accompanied by odor from the face (yeast infection of skin folds requires treatment)
- Staining occurs on a dog with upright eyes and no obvious structural cause — may indicate blocked tear ducts that can be flushed or surgically corrected