Glaucoma in Dogs: Signs, Treatment and Breeds at Risk

What Is Glaucoma?

The eye constantly makes fluid, which normally drains out through a filter at the edge of the iris. When drainage is blocked, pressure builds up.^6,5 Normal eye pressure in dogs is roughly 10 to 25 mm Hg; glaucoma is diagnosed when it's higher, and pressures above 40 to 50 are an emergency.^8,1,12,13 Vets measure it painlessly with a handheld tonometer.⁶

Signs of Glaucoma in Dogs

• Red eye, especially red blood vessels on the white of the eye^4,2
• Cloudy or bluish cornea⁴
• A dilated pupil that responds poorly to light^6,7
• Squinting, tearing, rubbing the eye, or hiding and lethargy from pain^4,2
• Vision loss, which can be sudden^2,4
• In chronic glaucoma, an enlarged, bulging eye^4,6

Early signs can be vague and nonspecific. Any red, cloudy or painful eye should have its pressure checked.^4,5 See cloudy eyes in dogs.

Types of Glaucoma and Breeds at Risk

Primary glaucoma is inherited. It usually affects one eye first, but the other eye is very likely to follow.^5,12 Breeds at risk include American Cocker Spaniels, Basset Hounds, Beagles, Chow Chows, Shar-Peis, Boston Terriers, Siberian Huskies, Samoyeds, Norwegian Elkhounds, Great Danes, Jack Russell Terriers and Shiba Inus.^5,4,8,10 It often first appears around 6 to 7 years of age.¹⁴

Secondary glaucoma is caused by another eye problem and usually affects one eye. Common causes include cataracts and the inflammation they cause, a dislocated lens, uveitis, bleeding in the eye and tumors.^5,11 Secondary glaucoma is the more common type overall.⁴ See cataracts in dogs.

Emergency Treatment

The first goal is to bring the pressure down as fast as possible to save any remaining vision and relieve pain.^2,13 Vets use eye drops such as prostaglandin analogs, which can lower pressure quickly, and sometimes medication given by injection; the vet checks the lens position first, because some drops can worsen a dislocated lens.^12,15 Your dog may then be referred to a veterinary ophthalmologist.⁵

Long-Term Treatment

There's no cure for glaucoma; treatment is lifelong.⁵ Common drop types include prostaglandin analogs (such as latanoprost), carbonic anhydrase inhibitors (such as dorzolamide) and beta-blockers (such as timolol), often combined.^6,12,4 Your vet sets the drugs and schedule, and regular pressure checks show whether they're working.⁵ Treatment and monitoring are lifelong, so don't stop drops without talking to your vet. Never use human or leftover glaucoma drops; some drugs can make certain types of glaucoma worse.^5,15

Protecting the Other Eye

In primary glaucoma, the second eye is at high risk.^5,12 Preventive drops can delay it: in one multicenter trial, untreated second eyes developed glaucoma after a median of 8 months, compared with about 31 months with preventive treatment.⁹ Ask your vet about starting preventive drops and checking pressure in the healthy eye regularly.^5,9

Surgery for Glaucoma

• To try to save vision: laser treatment that reduces fluid production, or a drainage implant. These are done by veterinary ophthalmologists.^5,12,6
• For a blind, painful eye: removing the eye (enucleation) or placing a prosthesis inside it relieves pain permanently.^5,6,1 Most dogs adapt very well after an eye is removed.¹⁶

Outlook for Dogs With Glaucoma

The outlook depends on how quickly treatment starts. Even with treatment, primary glaucoma is progressive, and many dogs eventually lose vision.^12,7 The main long-term goal is keeping your dog comfortable. Blind dogs can adapt well.¹⁷ If a blind eye stays painful, removing it relieves the pain.^4,15

Frequently Asked Questions

What are the first signs of glaucoma in dogs?

A red eye, a cloudy or bluish cornea, a large pupil, squinting or tearing. Any of these needs an eye-pressure check the same day.

Is glaucoma painful for dogs?

Yes. High eye pressure is painful, though dogs often hide it. Signs include squinting, rubbing the eye, hiding and sleeping more.

How fast can a dog go blind from glaucoma?

Very fast. Permanent damage can happen within 24 to 48 hours of a sudden pressure rise.

Can glaucoma in dogs be cured?

No, but it can be managed with lifelong drops, and surgery can save vision in some dogs or relieve pain in a blind eye.

Which dog breeds are prone to glaucoma?

American Cocker Spaniels, Basset Hounds, Chow Chows, Shar-Peis, Beagles, Boston Terriers, Siberian Huskies, Samoyeds and Shiba Inus are among the breeds at highest risk.

Can a dog live comfortably with glaucoma?

Yes, if the pressure is controlled or a painful blind eye is removed. Most dogs adapt well to vision loss.

Can cataracts cause glaucoma in dogs?

Yes. Inflammation from cataracts is a leading cause of secondary glaucoma, which is why dogs with cataracts need regular eye checks.

Can I treat my dog's glaucoma at home?

No. Glaucoma needs prescription drops and regular pressure checks. Home remedies can't lower eye pressure, and delays cost vision.