Glaucoma in Dogs: Causes, Symptoms & Treatment

Glaucoma in dogs is a painful condition that can lead to blindness. While there is no cure for the disease, early detection ensures the best outcome for your pet. That’s why it’s important to watch for symptoms at home, and to make sure your dog is routinely seen by their veterinarian.

Read on to discover how to identify the signs of glaucoma and learn about common options to treat it.

What is Glaucoma in Dogs?

Glaucoma is a progressive condition in which pressure builds inside the eye, causing pain and vision loss. 

The disease occurs when excess fluid accumulates in the front part of the eye. In a healthy eye, this fluid is produced at the same rate that it’s drained. In glaucoma, the drainage system becomes obstructed, causing pressure to build.

This excessive pressure damages the optic nerve – which is responsible for relaying visual information from the eye to the brain – as well as the retina. As a result, glaucoma in dogs can lead to poor eyesight and pain. The condition is more common in older dogs.

What Causes Glaucoma in Dogs?

There are two different types of glaucoma in dogs: primary and secondary. 

Primary glaucoma is inherited. With primary glaucoma, it’s important to understand that if one eye is affected, it’s highly likely the other one will be, too.

Secondary glaucoma, on the other hand, is caused by inflammation inside the eye. This may be a result of injury or disease to the eye itself, such as bleeding from blunt-force trauma, retinal detachment, tumors, infections, cataracts or lens displacement. With secondary glaucoma, the condition may just occur in the one eye.

Symptoms of Glaucoma in Dogs

The symptoms of canine glaucoma need to be caught early in order to prevent further damage and save the eye. Here’s what you should look for: 

• Cloudy eye – may be foggy or hazy with a blue tinge 
• Redness – from congestion of blood vessels around the eye 
• Pupil dilation 
• Loss of vision – you might notice your dog being clumsier than usual, perhaps bumping into things 
• Lethargy – your dog may be less active than normal 
• Squinting or blinking more often 
• Watery eye discharge 
• Eye pain – your dog might flinch or turn away if you touch that side of their head

Symptoms of glaucoma in dogs can appear rapidly, so be sure to contact your veterinarian as soon as possible if you see them.

Diagnosing Glaucoma in Dogs

To diagnose glaucoma, your veterinarian will likely first test the pressure of your dog’s eye by using a device called a tonometer on the surface of the eye.

While the normal pressure in a dog’s eye is between 10 and 25 mmHg (millimeters of mercury), the pressure in an eye with glaucoma can measure between 45 and 65 mmHg. This can be extremely painful for your dog.

If your veterinarian diagnoses your pet with glaucoma, they may refer you to a veterinary ophthalmologist for further examination. They’ll thoroughly examine both eyes and may use gonioscopy, a technique in which a special contact lens is placed on the eye to assess the structures involved in fluid drainage inside the eye.

Another specialist technique is electroretinography, which measures the response of the retina to light stimulation. This can help determine the potential of your dog’s vision with treatment.

Treating Glaucoma in Dogs

Unfortunately, there’s no cure for glaucoma in dogs. However, for primary glaucoma, there are some treatment options available to reduce pressure and make the eye more comfortable. These include the use of medicated eye drops or surgery to improve the fluid drainage in the eye.

For secondary glaucoma, the treatment required depends on the underlying cause. Your veterinarian will determine the best option based on your dog’s specific condition and factors such as their medical history.

It’s important to understand that if the disease is too advanced or treatment is unsuccessful, then your dog will likely become permanently blind, and the eye may need to be removed if it’s causing pain.

Preventing Glaucoma in Dogs

You can reduce the risk of secondary glaucoma by keeping your dog safe and healthy. Avoid situations that may lead to potential accidents or injuries, tend to health issues, and obtain treatment for any infections as soon as possible, especially those related to the eye.

There’s nothing that can be done to prevent primary glaucoma, but there are certain eye tests that can determine whether dogs possess any known inherited eye conditions.

If you’re adopting a dog, ask the shelter or adoption agency about known health problems and have them checked by your veterinarian as soon as possible. Purchasing your pet? Buy from a reputable breeder, and check that there is no history of inherited conditions.

If primary glaucoma is identified in one eye, your veterinarian may recommend medicating the other eye before signs develop.

While it may be easy to overlook, your dog’s eye health is important and affects their overall well-being. By regularly checking your pet’s eyes for unusual symptoms and maintaining consistent visits with your veterinarian, you can catch glaucoma early and increase your dog’s chances of living a happy, healthy life.

Want more expert tips for your canine companion? Explore our library of dog symptoms articles.