Pannus in dogs, also called chronic superficial keratitis, is an immune-mediated inflammation of the cornea: a pink, fleshy film of blood vessels creeps across the clear front of the eye, usually from the outer edge, and dark pigment follows behind it. It isn't curable, but daily prescription eye medication controls it in most dogs, and dogs diagnosed early usually keep useful vision for life. German Shepherds, Belgian Tervurens, Greyhounds and dogs living at high altitude carry the highest risk.
What pannus looks like, and where it starts
Pannus almost always affects both eyes, though one is often worse. The first sign is a reddish-pink, slightly raised haze at the outer (ear-side) edge of the cornea, most often in the lower-outer corner. Over months it spreads toward the center. Brown or black pigment then settles into the inflamed area, which is what turns an eye "muddy" or dark.
Watch the third eyelid too. In a study of 308 German Shepherds with pannus in Poland and Slovakia, 63–69% also had a thickened, depigmented third-eyelid margin (Drahovska et al., 2014). This form is sometimes called atypical pannus or plasmoma, and it can show up before the cornea changes. If you've noticed a pink, puffy membrane in the inner corner, compare it with our guide to dog third eyelid showing.
Most dogs with pannus aren't in obvious pain, which is why it gets missed until pigment covers much of the cornea. Left untreated, it can lead to blindness (Jokinen et al., 2011).
Which dogs get pannus: the risk numbers
The key risk study drew on 16 US veterinary teaching hospitals and 595 affected dogs at Colorado State University (Chavkin et al., 1994):
- Breed: Belgian Tervurens, German Shepherds, Border Collies, Greyhounds, Siberian Huskies and Australian Shepherds were disproportionately affected.
- Age: dogs aged 4–7 were 2.36 times more likely to develop lesions than dogs under 4.
- Altitude: dogs living above 7,000 feet were 7.75 times more likely to develop pannus than dogs living between 3,000 and 5,000 feet. Think German Shepherds in Santa Fe, Park City or Breckenridge.
- Genes: pannus in German Shepherds has an inherited side. One immune-system (MHC class II) haplotype was linked to pannus, and dogs carrying two copies of it had roughly 8.5 times the odds of disease (Jokinen et al., 2011).
Why altitude, and not just sunshine?
Ultraviolet light is widely believed to aggravate pannus, which is why dog goggles are sold for it. The data are more nuanced. In the US study, disease rates tracked altitude but not average solar radiation. And when researchers fitted UV-blocking contact lenses to one eye of 26 dogs for six months, alongside cyclosporine, they could not show any benefit over the untreated eye (Denk et al., 2011). Shade and goggles are reasonable extras at altitude or on snow, never a replacement for the prescription.
Pannus stages: what you'll see at home
Vets don't all use the same grading chart, so treat this as an owner's guide rather than an official scale.
| Stage | What you see | What it usually means |
|---|---|---|
| Early | Pink haze or fine vessels at the outer edge; third-eyelid margin losing its dark rim | Best moment to start treatment; clarity is usually fully preserved |
| Moderate | Fleshy pink tissue covering part of the cornea; brown pigment at its leading edge | Inflammation responds well; some pigment may stay |
| Advanced | Dark pigment across much of the cornea; bumping into things in dim light | Vision already reduced; specialist options may be discussed |
| Controlled | Pale, quiet eye; old pigment stable, no new pink tissue | The goal. Maintenance drops continue for life |
Pannus or something else?
- Cloudy eye from inside: a bluish-gray center is usually lens aging or a cataract, deep inside the eye, not on its surface. See dog cloudy eye.
- Dry eye (KCS): sticky discharge and a dull cornea that can also pigment. The two can coexist, so vets check tear production. See dry eye in dogs.
- Pigmentary keratitis: in Pugs and Shih Tzus, pigment comes from friction and exposure, a different cause.
- Corneal ulcer: painful, with squinting and tearing. This matters, because steroid drops used for pannus can worsen an ulcer.
If you're unsure whether you're looking at inflammation or an infection, our guide to the warning signs of a dog eye infection walks through the differences.
How vets diagnose and treat pannus
Diagnosis is mostly clinical: breed, age and the typical outer-edge pattern in both eyes. Your vet will usually stain the eye to rule out an ulcer before prescribing steroids, and measure tear production.
Treatment combines a topical corticosteroid with an immunomodulator such as cyclosporine or tacrolimus, given several times a day at first and then tapered to the lowest dose that keeps the eye quiet. In a Polish clinical study of 41 dogs, five weeks of dexamethasone plus cyclosporine drops cut the average number of corneal quarters invaded by vessels from about 2.6 to between 0.2 and 0.6, and roughly halved the inflamed corneal area (Balicki et al., 2021). Stubborn cases may be offered steroid injections, surgery or radiation therapy at a referral center.
What treatment can and can't change
In the same study, pigment kept increasing in 27 of 77 corneas even while inflammation receded. The practical lesson: redness and vessels clear within weeks, but pigment and scarring that are already there may stay. The earlier you start, the more clear cornea you keep. Stopping the drops once the eye looks better is a classic reason pannus comes back.
A daily routine that makes lifelong drops easier
- Clean first. Gently rinse away crust and discharge so the prescription reaches the cornea instead of sitting on debris.
- Wait about five minutes, then apply the prescribed drop or ointment. If there are two medications, space them out the same way.
- Take a monthly photo of each eye in the same light and at the same angle. Pigment creep is slow and easy to miss day to day.
- Keep every recheck, especially in the first three months, when your vet adjusts the dose.
- Offer shade at midday at altitude or on snow, as a comfort measure.
For step one, we made our gentle daily dog eye drops for eyes that are already sensitive. A dog with pannus is medicated two or three times a day for years, so the cleaning step has to be sting-free. Here is what's in the bottle:
| Feature | Typical 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 |
| Moisturizing active | Usually none | Sodium hyaluronate (hyaluronic acid) 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% |
| Alcohol / fragrance | Common | None |
To be clear about limits: these are non-medicated hygiene drops. They don't treat pannus or replace cyclosporine, tacrolimus or steroids. They're the comfortable clean-up that makes the prescribed routine easier to stick to, and they help keep tear staining off the face. Made in Canada, 120 mL, with free worldwide shipping. You can browse the rest of our dog eye care products here.
When to call your vet
- Any new pink film at the outer edge of the eye in a German Shepherd, Greyhound, Husky or Tervuren over age 3.
- Squinting, pawing or a tightly closed eye, which suggests an ulcer rather than pannus.
- A sudden cloudy, blue or enlarged eye, which needs a same-day visit.
- Pink tissue returning after the dose was lowered.
Frequently asked questions
How long can a dog live with pannus?
A normal lifespan. Pannus affects the eyes, not overall health. What's at stake is vision, and consistent treatment preserves it in most dogs.
Is pannus painful for dogs?
Usually not. Most dogs with pannus don't squint or rub their eyes. If your dog does, ask your vet to check for a corneal ulcer or another problem.
Can pannus in dogs be cured?
No, but it can be controlled. Prescription drops calm the inflammation within weeks, and a low maintenance dose keeps it quiet long-term.
Should a dog with pannus be bred?
Pannus has a genetic component, and a risk haplotype has been identified in German Shepherds. Discuss it with your breeder and vet before breeding an affected dog.
Scientific References
- Chavkin MJ, Roberts SM, Salman MD, Severin GA, Scholten NJ. Risk factors for development of chronic superficial keratitis in dogs. Journal of the American Veterinary Medical Association. 1994;204(10):1630-1634. PMID 8050943
- Jokinen P, Rusanen EM, Kennedy LJ, Lohi H. MHC class II risk haplotype associated with canine chronic superficial keratitis in German Shepherd dogs. Veterinary Immunology and Immunopathology. 2011;140(1-2):37-41. PMID 21144596
- Drahovska Z, Balicki I, Trbolova A, Mihalova M, Holickova M. A retrospective study of the occurrence of chronic superficial keratitis in 308 German Shepherd dogs: 1999-2010. Polish Journal of Veterinary Sciences. 2014;17(3):543-546. PMID 25286670
- Balicki I, Szadkowski M, Balicka A, Zwolska J. Clinical study on the application of dexamethasone and cyclosporine/dimethyl sulfoxide combination eye drops in the initial therapy of chronic superficial keratitis in dogs. Polish Journal of Veterinary Sciences. 2021;24(3):415-423. PMID 34730300
- Denk N, Fritsche J, Reese S. The effect of UV-blocking contact lenses as a therapy for canine chronic superficial keratitis. Veterinary Ophthalmology. 2011;14(3):186-194. PMID 21521443
Veterinary disclaimer: This article is educational and is not a substitute for veterinary diagnosis or treatment. Pannus needs to be diagnosed and managed by a licensed veterinarian in the US or Canada. 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 the FDA or Health Canada as drugs.