Recognizing and Treating Corneal Ulcers in Dogs and Cats

If your dog or cat gets a scratch from a claw or a foxtail, it can cause a corneal ulcer, leading to squinting, tearing, and cloudiness. Use an Elizabethan collar to prevent rubbing, and treat simple ulcers with tobramycin drops 3–4 times daily. For infected or deep ulcers, your vet may prescribe fluoroquinolones every 2–4 hours and topical serum. Atropine helps with pain, while conjunctival grafts or grid keratectomy may be needed for severe cases. Fluorescein staining confirms the ulcer; proper care prevents vision loss in just days-watch the signs closely and act fast if things worsen.

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Notable Insights

• Trauma, feline herpesvirus, dry eye, abnormal eyelashes, and brachycephalic anatomy are leading causes of corneal ulcers in pets.
• Squinting, tearing, light sensitivity, corneal cloudiness, and visible defects are common signs of corneal ulcers.
• Fluorescein staining, tear testing, tonometry, and full eye exams are essential for accurate diagnosis.
• Simple ulcers heal with topical antibiotics; infected or melting ulcers require aggressive therapy like frequent fluoroquinolones and serum.
• Surgery such as grid keratectomy or conjunctival grafts may be needed for chronic or deep ulcers to prevent perforation.

What Causes Corneal Ulcers in Dogs and Cats?

While your pet might seem perfectly fine one minute, a corneal ulcer can develop quickly after even minor eye trauma, so it’s important to know the common causes. Trauma-like scratches from fights, claws, or foreign bodies such as foxtails and sand-is the leading cause of corneal ulcers in dogs and cats. In cats, feline herpesvirus (FHV) directly causes corneal epithelial defects, with flare-ups during stress. Dry eye (keratoconjunctivitis sicca) reduces tear production, leaving the cornea vulnerable. Abnormal eyelashes, including ectopic cilia or distichiae, mechanically irritate the surface, often leading to chronic ulcers. Brachycephalic breeds, like Pugs and Boston Terriers, are at higher risk due to prominent eyes and incomplete blinking. These conditions create entry points for bacterial infections, worsening damage. Identifying the underlying cause-whether trauma, infection, or anatomy-is key to effective treatment and long-term eye health for your pet.

How Can I Tell If My Pet Has a Corneal Ulcer?

How can you tell if your dog or cat has a corneal ulcer? Look for key clinical signs like squinting or complete blepharospasm, which often signal severe eye pain. Your pet may avoid bright light and produce excessive tearing or watery discharge that turns yellow or green if infection sets in. Redness around the eye and a cloudy cornea-sometimes bluish due to fluid in the stroma-are common. While you can’t perform a fluorescein stain test at home, knowing that it reveals damaged areas as bright green helps you understand your vet’s diagnosis. If you notice a visible divot or bulge, seek emergency care-deep ulcers risk rupture. Never delay: early recognition of these signs means faster treatment and better outcomes for your pet’s vision and comfort.

How Is a Corneal Ulcer Diagnosed?

What signs should you watch for if you suspect your pet has a corneal ulcer? Look for squinting, redness, or cloudiness-these often point to corneal ulceration. Your vet will start with a thorough ophthalmic examination to assess the eye’s surface and rule out deeper issues like Descemets membrane exposure. They’ll use a fluorescein stain, which binds to damaged areas, turning them bright green under blue light-this confirms a corneal ulcer, especially superficial ulcers. A Schirmer tear test checks tear film quality and volume, helping identify dry eye as a cause. Tonometry measures intraocular pressure to exclude glaucoma or uveitis. These tools together give a clear picture of your pet’s eye health, ensuring accurate diagnosis and timely care for effective healing. Early detection makes all the difference.

Treating Simple vs. Infected Corneal Ulcers

A simple corneal ulcer usually clears up fast with the right care, and your vet will likely prescribe a topical antibiotic like tobramycin or triple antibiotic ointment to apply 3–4 times a day-these drops or ointments protect against infection while the surface heals, typically within 3 to 7 days. For pain management, your vet may add atropine drops once daily in dogs or via ointment in cats to reduce discomfort and prevent salivation. If you notice stromal opacity, white-to-tan infiltrate, or signs of uveitis, suspect infected ulcers or ulcerative keratitis. These require aggressive medical management, including fluoroquinolones every 2–4 hours and topical serum to preserve corneal stroma integrity. Any superficial corneal defect with infiltrate or severe pain should be treated as infected. Use topical serum every 2–4 hours in melting ulcers, and monitor closely with daily rechecks to guarantee healing.

When Medical Treatment Isn’t Enough: Surgical Options

If your dog or cat isn’t healing despite diligent use of antibiotic drops, pain meds, and serum treatments, it might be time to contemplate surgical options, especially when dealing with stubborn indolent ulcers or structural issues like entropion or ectopic cilia. Surgery becomes necessary when medical treatment fails, such as with spontaneous chronic corneal epithelial defects (SCCED), also known as indolent ulcers. A grid keratectomy can help these ulcers heal by removing damaged tissue. Deep corneal ulcers with stromal loss often require conjunctival grafts to prevent perforation, while embedded corneal foreign bodies must be removed surgically. Entropion or ectopic cilia also demand correction to stop ongoing damage.

How to Help Your Pet Heal and Prevent Future Ulcers

While your pet’s corneal ulcer is healing, sticking to the treatment plan makes all the difference, so be sure to apply topical antibiotics like chloramphenicol or ciprofloxacin exactly as prescribed-usually 3 to 4 times daily, every 6 to 8 hours, without skipping doses. Always use an Elizabethan collar to prevent scratching, which can reinjure the corneal surface. Apply artificial tear ointment between medication doses to keep the eye moist, especially if your pet has keratoconjunctivitis sicca. If feline herpesvirus is suspected, your vet may prescribe famciclovir to slow viral replication. Rechecks are essential-your vet will use fluorescein staining to confirm when epithelial cells have fully covered the defect. Don’t stop treatment early. Address eyelid abnormalities like entropion surgically, since they delay the healing process and lead to recurrence.

On a final note

You’ve got this, and so does your pet. Catching corneal ulcers early with a fluorescein stain test, using prescribed antibiotic ointments like Terramycin, and following up in 48 hours guarantees healing. For deep ulcers, surgery like a conjunctival graft may be needed. Keep your pet’s face clean, trim facial hair, and use an Elizabethan collar to prevent scratching-most ulcers heal fully with prompt, precise care.