Glaucoma in Cats

Glaucoma is an eye condition caused by an abnormally high amount of pressure that builds up in the eye. The eye maintains a constant production and drainage of the fluid in the eye, called aqueous humor. When there is a problem with the drainage of this fluid, pressure builds within the eye. This high pressure can have severe side effects including damage to the optic nerve, which can result in blindness.

Although glaucoma is common in dogs and people, it is rare in cats and often secondary to underlying disease.

Glaucoma is a very painful condition; its most common sign is bulging eyes. Glaucoma usually starts in one eye but can progress into the other eye, depending on the cause. Because glaucoma is so painful, your pet might not eat, could be irritable, and might avoid being touched. She may sleep more than normal, avoid sunlight, and have vision issues. Her eyes could look bloodshot and/or cloudy, might tear, and will probably have the telltale bulging shape.

Glaucoma can be caused by a structural problem within the eye or can result as a secondary problem from another disorder, underlying disease condition, or trauma (most common in cats).


In order to diagnose your cat’s eye condition, your veterinarian will perform a complete history, physical exam, and eye exam. Additionally, they may recommend the following, depending on your cat’s specific needs:

  • A separate visit to a veterinary ophthalmologist, who specializes in eye diseases
  • Tonometry, which measures pressure inside of the eye
  • X-rays to identify any abnormalities or tumors
  • An ultrasound of the eye to identify any abnormalities or tumors
  • Gonioscopy, which is a specific examination of the front part of the eye
  • Blood tests to determine the underlying cause. These may include:
  • Chemistry tests to evaluate kidney, liver, and pancreatic disease and function, as well as sugar levels
  • A complete blood count , urinalysis, thyroid test, and tests for feline leukemia and feline immunodeficiency virus, to rule out underlying disease whether infectious, metabolic, or inflammatory
  • Specialty tests such as cultures, PCR testing, and titers

Your veterinarian will recommend a course of treatment specific to your feline friend. Treatment may include a variety of medications to help reduce the pressure within her eyes. Depending on the cause, other medications or treatments may help treat the underlying condition. Different types of surgical therapy may be recommended in an attempt to keep the pressure in the eye controlled. In long-term cases, surgical removal of the eye may be recommended as a last resort because glaucoma is such a painful condition for your pet.

While glaucoma can’t necessarily be avoided, you can catch it early enough to be managed well. Routine visits to your veterinarian are extremely important so that conditions such as glaucoma can be identified before they have progressed. If you notice anything out of the ordinary about your cat’s eyes, contact your veterinarian immediately.

If you have any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.

Related symptoms: