What are Corneal Ulcers in Dogs?
The cornea is the transparent, front portion of the eye. In dogs, corneal ulcers are painful lesions that develop on its surface.
Main causes of corneal ulcers are:
Trauma such as scratches, pawing, foreign objects (like thorns), or blunt trauma
Underlying eye conditions such as dry eye, eyelid abnormalities (entropion or ectopic cilia), and spontaneous chronic corneal epithelial defects (SCCEDs)
Bacterial or viral infections
Written by Dr. Mariella Roberts, Veterinary Surgeon, Animal Trust Vets CIC | Published September 2025 | Review date September 2027 | This advice is for UK pets only and is not a replacement for seeing a vet
Symptoms Corneal Ulcers in Dogs
Pain: squinting, excessive blinking, pawing at the eye.
Redness and inflammation: bloodshot appearance.
Discharge: watery or thick, yellow/green discharge.
Cloudy or hazy appearance: may look like a "hole" or depression in the cornea.
Light sensitivity: avoiding bright light
When to contact your vet
Any signs of an eye ulcer, especially if the dog is squinting, pawing at the eye, or has discharge
If the ulcer appears deep or doesn't improve with initial treatment
If the dog is in severe pain
Diagnosis of Corneal Ulcers in Dogs
History and clinical examination of the eye.
A drop of fluorescein dye is applied to the cornea. If there's an ulcer, the dye will adhere to the damaged area and appear green under a special light. This helps pinpoint the ulcer's location and extent.
Other tests may be needed if the ulcer is deep or not healing.
Treatment of Corneal Ulcers in Dogs
Most corneal ulcer will heal within 5-7 days with:
Antimicrobial eye drops may be used if sufficient evidence an infection exists.
Pain killers
Lubricants to keep the eye moist may be used in some situations.
E-collar (cone): to prevent your dog from rubbing or scratching the eye
Debridement: in some cases, dead or poorly healing tissue may need to be removed (debrided) to promote healing. This can be done conscious in some cases.
Surgery in severe cases (deep ulcers, SCCEDs or those that don't respond to other treatments), may be needed to stabilise the cornea or remove foreign bodies.
Prevention
While not all corneal ulcers in dogs are preventable, proactive measures can significantly reduce the risk:
observing your dog's eyes for any signs of irritation.
managing underlying conditions such as dry eye, entropion, etc.
taking precautions during activities to minimise the chance of injury such as avoid areas with long grass and thorny bushes, supervise interaction with other animals from scratches or bites, avoid your dog hung his/her head out of the car’s window during travelling.
Outlook
The outlook for corneal ulcers in dogs is generally good with prompt and appropriate treatment, with most healing within a week. However, complications like infection or non-healing ulcers can arise, potentially leading to more serious outcomes like blindness or even loss of the eye if left untreated.