Causes of Cloudy Eyes in Dogs: What’s Happening To My Dog’s Eyes?

Potential causes of cloudy eyes in dogs are mostly of the scary kind.

Noticing cloudy appearance in your dog’s eyes is scary. Is my dog losing their sight? Is it cataracts? I’d rather rush to a vet thinking my dog is having cataracts and find out it is nuclear sclerosis than figure it’s nuclear sclerosis and leave my dog hanging. Well, I’d rather my dog not have cloudy eyes in the first place. But that’s not always the option on the table.

Causes of Cloudy Eyes in Dogs: What's Happening To My Dog's Eyes?

Jasmine once suddenly started squinting, and her eye looked as if it had a dark blue screen over it. We rushed her to a vet. All that because of a renegade eyelash which decided to grow inward, hurting the eye. Jasmine did need to have that eyelash removed but once treated, her eye was perfectly fine after that.

What can cause cloudy eyes?

The first thing most people’s minds go when thinking cloudy eyes are cataracts. Cataracts are not, however, the only potential cause.

Causes of Cloudy Eyes in Dogs:: cataract vs nuclear sclerosis


A cataract is the loss of transparency of the lens. The impairment can range from minor to complete loss of sight. While typically thought to be associated with diabetes, the development of cataracts in dogs is often genetic in origin with some breeds more susceptible to the problem. As well as unlike in people, cataracts in dogs are most likely to develop between 1 and 5 years of age.

Cataracts that do develop due to diabetes can hit hard and fast. You should notice other signs of diabetes as well, though, such as increased drinking and urination …

Other symptoms of cataracts include:

  • eye irritation
  • redness
  • eye discharge
  • excessive blinking
  • rubbing at the eyes
  • clumsiness
  • reluctance to climb stairs or jump on furniture

Nuclear/Lenticular Sclerosis

Nuclear sclerosis is cataracts’ harmless cousin. What ends up with similar cloudy appearance is a result of hardening of the lens with age. Unlike a cataract, though, nuclear sclerosis only has a moderate impact on vision, particularly in low light conditions.

Other symptoms of nuclear sclerosis might include:

  • reduced vision in low light conditions
  • a decrease in distance or depth perception

This condition doesn’t cause any pain or unpleasant sensations, it only moderately interferes with vision, particularly in the dark.

Cookie, our Rottie, apparently has a little bit of nuclear sclerosis. I haven’t noticed anything but her veterinarian did during a wellness exam which includes an ophthalmologic exam. She expects her having some vision issues in darker conditions–I am not sure I can detect any. I can say with confidence that her eyesight is impressive during the day.

There is no indicated treatment for nuclear sclerosis, and it doesn’t really need any.

I tell my clients that if their dogs had to read the fine print on a bank statement, they might be in trouble, but to live a dog’s life, they’re fine.

Dr. Jennifer Coates

You can read Dr. Coates’ explanation of the difference between cataracts and nuclear sclerosis in her article, Is it a Cataract or Lenticular Sclerosis? I always enjoy how she explains things.


Uveitis is inflammation of the dark tissue at the front of the eye. Therefore it also hurts. It too can threaten your dog’s vision.

Causes include the typical laundry list of potential culprits with any inflammation: infections, trauma, autoimmune diseases, or tumors. Just one that is different – lens protein seeping into the eye fluid. The last one sounds weird; it’s usually a result of cataracts (just so we make a full circle, I guess).

And, don’t forget, it hurts too.

Other signs can include:

  • redness
  • excessive tearing
  • eye discharge
  • swelling
  • small or oddly-shaped pupils
  • and squinting because it hurts


The first thing you need to know about glaucoma is that it hurts. A lot. A lot a lot. Did I mention that it hurts?

Glaucoma is increased pressure within the eye. This can happen because of an anatomical abnormality in the drainage angle, or as a result of an injury or disease of the eye. And it hurts. It is likely to eventually lead to blindness. Oh, and before I forget to say it, it hurts.

Beside cloudy appearance in the eye, your dog will likely act miserable, blinking or squinting. Pupils might not respond to light, and the whites of the eyes might look red due to dilated blood vessels.

Other things that can cause cloudy eyes include a variety of corneal diseases and disorders. These will cause a change in color on the surface of the eye rather than within the eye.

Other symptoms of glaucoma can include:

  • squinting
  • reluctance to open the eye
  • rubbing at the eye
  • watery discharge
  • swelling of the eyeball
  • loss of appetite
  • lethargy
  • blindness

Other potential causes

Other eye conditions that can result in cloudy appearance include things such as corneal edema/corneal endothelial degeneration, corneal deposits, dry eye, corneal ulcers, or pannus.

Endothelial degeneration/corneal edema

There are cells in the cornea which have the job of keeping it relatively dehydrated. As they fail in their function, it allows fluid accumulation which can progress to corneal edema. As the name indicates, the cornea fills with fluid and swells. The resulting cloudy appearance is similar to a steamed-up window even though it does have a blue tint.

It can be caused by advanced age, inflammation or a complication of eye surgery

Source: Willows; Specialist Referral Service

Corneal lipidosis

Corneal lipidosis is the deposition of cholesterol in the eye. It can be a result of inherited corneal dystrophy, corneal degeneration, or due to high blood cholesterol levels.

Source: Northwest Animal Eye Specialists

Related articles:
Eye Discharge in Dogs: What Is That Goop In My Dog’s Eyes?

Further reading:
5 Diseases That Cause Blue Eyes in Dogs

Categories: Cloudy eyesConditionsEye diseasesSymptoms

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Jana Rade edited by Dr. Joanna Paul BSc BVSc

I am a graphic designer, dog health advocate, writer, and author. Jasmine, the Rottweiler of my life, was the largest female from her litter. We thought we were getting a healthy dog. Getting a puppy from a backyard breeder was our first mistake. Countless veterinary visits without a diagnosis or useful treatment later, I realized that I had to take Jasmine's health care in my own hands. I learned the hard way that merely seeing a vet is not always enough. There is more to finding a good vet than finding the closest clinic down the street. And, sadly, there is more to advocating for your dog's health than visiting a veterinarian. It should be enough, but it often is not. With Jasmine, it took five years to get a diagnosis. Unfortunately, other problems had snowballed for that in the meantime. Jasmine's health challenges became a crash course in understanding dog health issues and how to go about getting a proper diagnosis and treatment. I had to learn, and I had to learn fast. Helping others through my challenges and experience has become my mission and Jasmine's legacy. I now try to help people how to recognize and understand signs of illness in their dogs, how to work with their veterinarian, and when to seek a second opinion. My goal is to save others the steep curve of having to learn things the hard way as I did. That is the mission behind my blog and behind my writing. That is why I wrote Symptoms to Watch for in Your Dog, which has turned out being an award-winning guide to dog owners. What I'm trying to share encompasses 20 years of experience. Dr. Joanna Paul BSc BVSc is our wonderful sponsor and has been kind to edit and fact-check my important articles.

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