Top 5 Most Common Eye Conditions in Pets

Animals are known for their superior senses, and when one is compromised by disease, their wellbeing and overall function is threatened. Your pet’s eyes do much more than scan the backyard for squirrels and watch for the mailman—they allow your furry friend to move confidently through the world. Prompt, expert treatment of eye conditions is paramount to preserving your pet’s vision, and quality of life. Fortunately, VRC’s ophthalmology department, led by our board-certified veterinary ophthalmologist, has experience in treating a spectrum of ocular conditions—from simple corneal ulcers, to challenging diseases. Here we highlight the five most common eye conditions in pets, so you can watch for warning signs, and alert your family veterinarian if you suspect your pet has an ocular problem.

#1: Corneal ulcers in pets

A corneal ulcer is an abrasion, scratch, or deeper wound on the surface of your pet’s eye. In dogs, corneal ulcers are often caused by ocular trauma, such as a scratch from another animal, or when a dog rubs its own eye. In cats, corneal ulcers commonly develop secondary to a herpesvirus infection, which also causes upper respiratory signs. Eye conditions that cause chronic corneal inflammation, such as keratoconjunctivitis sicca (i.e., “dry eye”) or abnormal eyelash growth, can also cause a corneal ulcer. Corneal ulcers are painful, and signs often include:

  • Redness
  • Squinting
  • Tearing
  • Ocular discharge
  • Cloudy-looking cornea


Corneal ulcers are diagnosed by applying a temporary stain that adheres only to damaged corneal areas. Most corneal ulcers are superficial, and resolve quickly with eye medications; however, deeper ulcers threaten to cause eye rupture, and may require longer, more intensive treatment, and possibly surgery, to preserve vision. 

#2: Keratoconjunctivitis sicca (KCS) in pets

KCS, commonly referred to as “dry eye,” is a condition that involves inadequate tear production, or poor quality tears that do not properly lubricate the eye surface. The dry cornea becomes easily traumatized and inflamed, leading to signs that may include:

  • Redness
  • Thick, mucousy ocular discharge
  • Squinting
  • Cloudy-looking cornea 


KCS is most often caused by immune-mediated tear gland destruction, but other causes are possible, including:

  • Drug reactions
  • Prolapsed third eyelid gland (i.e., “cherry eye”)
  • Third eyelid gland excision
  • Infectious, congenital, and endocrine diseases

KCS is common in dogs, with some breeds at higher risk, including Cavalier King Eye Conditions in DogsCharles Spaniels, English Bulldogs, Lhasa Apsos, Pugs, Shih Tzus, and West Highland White Terriers.

Prompt diagnosis and treatment is important, as uncontrolled KCS can lead to corneal vascularization, pigmentation, and scarring, which can limit your pet’s vision. Treatment is life-long, and involves eye medication to stimulate tear production, and reduce inflammation. 

#3: Cataracts in pets

A cataract is an opacity of your pet’s normally clear lens that interferes with the lens’ ability to properly focus light on the retina. Sometimes only part of your pet’s lens can be affected, but if the entire structure, or a large portion, becomes opaque, the formed light beam cannot reach the retina, causing poor vision. You may notice your pet’s eye changea cataract appears as a white spot or haze in the eye’s center. 

Most cataracts are hereditary, and affect high-risk breeds, such as:

  • Bichon Frises
  • Boston Terriers
  • Cocker Spaniels
  • Fox Terriers
  • Havanese
  • Miniature Schnauzers
  • Poodles
  • Silky Terriers 


Cataracts can also develop secondary to injury, inflammation, or systemic diseases, such as diabete mellitus. 

A cataract is diagnosed through a thorough eye exam by a veterinary ophthalmologist. Unfortunately, no medical treatment is available to slow or reverse cataract formation, and only surgical lens replacement will restore an affected pet’s vision.

#4: Glaucoma in pets

Your pet’s eyes are filled with fluid (i.e,. aqueous humor) that is constantly produced and drained. Glaucoma results when a buildup of fluid, typically from impaired drainage, increases intraocular pressure. Excess pressure on the delicate retina, which houses vision receptors, can rapidly lead to irreversible blindness, making glaucoma a medical emergency. Glaucoma is painful, and pets may exhibit these characteristic signs:

  • Ocular redness
  • Tearing
  • Eye enlargement
  • Cloudy-looking cornea
  • Pawing at the eyes


Glaucoma is typically inherited, and is most often seen in high-risk breeds, including:

  • Basset Hounds
  • Beagles
  • Chinese Shar-Peis
  • Chow Chows
  • Cocker Spaniels
  • Great Danes
  • Jack Russell Terriers
  • Norwegian Elkhounds
  • Samoyeds
  • Siberian Huskies

Glaucoma can also develop secondary to ocular problems that interfere with fluid drainage, including trauma, anterior lens luxation, ocular inflammation, advanced cataracts, and intraocular masses. Glaucoma can affect one or both eyes, depending on the cause.

Glaucoma is diagnosed by measuring the affected eye’s intraocular pressure. If glaucoma is secondary to an underlying problem, treatment of the primary condition may normalize the pressure; however, most cases involve life-long management, including eye medication, and monitoring by a veterinary ophthalmologist. Despite treatment, some dogs become blind in the affected eye(s), and may require surgical eye removal (i.e., enucleation) to relieve chronic pain.

#5: Eyelid conformational abnormalities in pets

As some pets grow, their eyelids develop incorrectly, becoming disproportionately too short or long, which can lead to secondary eye problems. Entropion is a condition where a pet’s eyelid rolls inward toward the cornea, causing chronic irritation and secondary ulcers. This condition is hereditary in some dog breeds, particularly those with prominent skin folds, such as Chinese Shar-Peis and Chow Chows. Entropion requires surgical correction of eyelid position and length, and chronic irritation relief. 

Ectropion causes the eyelid margin to droop away from the eye surface. Without constant contact between the eyelid and the cornea, tears roll off, and the cornea becomes abnormally dry, dull-looking, mucousy, and more susceptible to irritation and ulcers. Ectropion is also breed-related, and pets with loose facial skin, such as Bloodhounds, have a higher incidence. Ectropion treatment involves surgery to shorten the eyelid margin. 

If an ocular condition threatens your pet’s precious vision, act quickly, and contact your family veterinarian or the VRC emergency service immediately. After initial evaluation, if your primary veterinarian determines your pet will benefit from the expertise of a board-certified veterinary ophthalmologist, contact us to schedule an appointment.