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What if dogs eyes turn blue?

Have you ever noticed your dog’s eyes change color as it grows up? It’s not uncommon for puppies to be born with blue eyes that darken over the first few months of life. But what if your adult dog’s eyes suddenly turned blue? What could cause this unusual eye color change?

Possible Causes of Blue Eyes in Adult Dogs

There are a few possible explanations for adult dog eyes turning blue:

  • Nuclear sclerosis – A normal age-related change where the lenses become opaque, resulting in a blue tint.
  • Cataracts – Clouding of the lenses that obstructs light from reaching the retina.
  • Glaucoma – Increased pressure within the eye that damages the optic nerve.
  • Eye injury or trauma – Hyphema, swelling, scarring, or bleeding can cause blue discoloration.
  • Genetics – Some breeds like Huskies and Dalmatians are predisposed to blue eyes.

While nuclear sclerosis is harmless in older dogs, the other conditions require veterinary attention to prevent vision loss. Let’s explore each cause and its treatments in more detail.

Nuclear Sclerosis

Nuclear sclerosis is a natural aging change that affects the lenses in dogs’ eyes. As dogs get older, the nuclei of their lenses gradually harden and become opaque. This normal thickening of the lenses causes a cloudy, bluish-gray appearance.

Nuclear sclerosis usually starts at around 6 years old and progresses slowly over time. It eventually results in blurred vision due to the reduced ability of light to pass through the cloudy lenses. However, it rarely leads to complete blindness.

Here are some key facts about nuclear sclerosis:

  • Most common in medium to large breed dogs over 6 years old
  • Causes a bilateral bluish-gray haziness in both eyes
  • Blurry vision, especially in low light conditions
  • No pain or discomfort associated with the condition
  • Does not always affect visual acuity if only mildly opaque
  • Gradual onset that worsens over time
  • No treatment needed unless vision impairment occurs

Since nuclear sclerosis is a normal aging change, there are no medications or surgical options to reverse or cure it. However, animals with advanced nuclear sclerosis resulting in significant vision problems may benefit from cataract surgery to restore their sight.


A cataract is an opacity or clouding that develops in the lens of the eye. The lens is normally transparent, but when a cataract forms, it blocks light from reaching the retina. This interference with light transmission results in blurred vision.

Cataracts appear as a blue-gray, milky white, or brownish coloration in the pupil. Small incipient cataracts may not affect vision, but larger cataracts can cause blindness if left untreated.

In dogs, cataracts have numerous causes including:

  • Diabetes mellitus
  • Eye trauma or injury
  • Inflammation
  • Radiation therapy
  • Toxicity from certain drugs
  • Old age
  • Hereditary conditions in some breeds

Symptoms of cataracts include cloudy pupils, vision problems, and a bluish discoloration to the eyes. Dogs may bump into objects, have difficulty navigating stairs, or seem reluctant to jump up or down from furniture.

Cataracts cannot be cured with medications, but surgery can often successfully restore vision. During cataract surgery, the cloudy natural lens is removed and replaced with an artificial lens implant. Your veterinarian may recommend surgery if the cataracts interfere significantly with your dog’s vision and quality of life.


Glaucoma refers to abnormally high pressure within the eye, which can damage the optic nerve and retina. It can lead to blue discoloration of the eye due to corneal edema and vision loss if untreated.

In dogs, the most common type is primary glaucoma. It results from inadequate drainage of aqueous humor due to structural abnormalities in the eye. Secondary glaucoma can occur due to eye injuries, inflammation, tumors, or lens dislocation.

Increased intraocular pressure causes fluid buildup in the cornea, resulting in a blue haze or clouding. Other symptoms include:

  • Dilated pupils
  • Redness in the white of the eye
  • Cloudiness
  • Enlarged or swollen eye
  • Retinal damage
  • Vision loss

Glaucoma requires immediate veterinary treatment to prevent irreversible vision loss. Medications can reduce fluid production and pressure inside the eye. Surgery may be done to improve drainage in the eye. Prompt treatment is essential to relieve pain and preserve sight.

Eye Injuries

Direct trauma to the eye can sometimes cause the cornea or surrounding tissue to become blue. Injuries like scratches, punctures, burns, or blunt force can result in swelling, bleeding, or damage.

Some common eye injuries that may lead to blue discoloration include:

  • Hyphema – Bleeding in the front of the eye due to blunt trauma or clotting issues.
  • Corneal ulcer – An open sore on the cornea, which can become infected.
  • Chemical burns – Damage from contact with irritants like cleaners, acids, etc.
  • Foreign objects – Corneal scratches or ulcers due to dirt, sticks, seeds etc.

Other symptoms of eye injuries include pain, discharge, squinting, redness, and impaired vision. Any eye trauma warrants prompt veterinary assessment to determine appropriate treatment and prevent complications.


Some breeds are predisposed to pale blue eyes due to genetics. Huskies, Dalmatians, Border Collies, Catahoula Leopard Dogs, and Australian Shepherds often have blue-eyed variants.

For these breeds, blue is considered a normal eye color passed down through selective breeding. However, blue eyes can indicate health issues in dogs not genetically prone to them.

In dogs with naturally blue eyes, the blue color results from a lack of pigment in the iris stroma. This allows light to pass through and showcase the blue color from the underlying retinal tissue.

While beautiful, pale blue eyes do make dogs more prone to certain eye disorders. Absence of iris pigment allows more damaging UV light into the eye, increasing the risk of conditions like corneal ulcers, uveitis, cataracts, and progressive retinal atrophy.

So in breeds where blue eyes are the norm, vigilant monitoring of eye health is important.

Diagnosing the Cause

If your adult dog’s eyes appear bluish-gray for the first time, schedule an appointment with your veterinarian. They will perform a full ophthalmic exam to determine the underlying cause and recommend appropriate treatment.

Diagnostic tests may include:

  • Ophthalmoscopy to examine internal eye structures
  • Tonometry to measure intraocular pressure
  • Fluorescein stain to check for corneal ulcers
  • Slit lamp exam to evaluate the front of the eye
  • Bloodwork to test for systemic diseases
  • Genetic testing for eye disease in some breeds

Based on your dog’s breed, medical history, exam findings and test results, your vet can diagnose whether the blue color is benign or a symptom of disease needing treatment.

When to See the Vet

Schedule an urgent vet visit if your adult dog’s eyes appear blue for the first time along with any of these warning signs:

  • Squinting, pawing at eyes, or showing signs of eye pain/discomfort
  • Redness in the whites of the eyes
  • Cloudy, milky bluish haze over the pupils
  • Sudden vision changes like bumping into objects
  • Discharge or crusting around the eyes
  • Swelling or enlargement of the eyes
  • Reluctance to go outside in sunny conditions
  • Recent eye trauma or injury

While bluish discoloration alone may not require immediate care, when paired with these symptoms it can signal an urgent eye problem needing veterinary attention.

In an older dog with no other symptoms, schedule a regular vet visit for evaluation. Nuclear sclerosis generally develops slowly and is not an emergency.


You can help prevent many disorders that cause blue eyes in dogs with these proactive measures:

  • Schedule annual eye exams to catch problems early
  • Control diseases like diabetes that increase cataract risk
  • Avoid trauma and injuries by keeping dogs leashed and wearing goggles
  • Don’t let dogs travel unrestrained in cars where debris can fly into eyes
  • Feed a diet rich in antioxidants for eye health
  • Avoid sun exposure during peak UV times for dogs prone to light sensitivity
  • DNA test dogs of high-risk breeds to make informed breeding decisions

While we can’t prevent all causes, staying vigilant about eye health is key to preserving vision and quality of life.

Treatment Options

Treatment for blue eyes in dogs depends on the underlying cause. Some options may include:

Condition Treatment Options
Nuclear Sclerosis No treatment usually needed unless vision significantly impaired, then cataract surgery may help
Cataracts Cataract surgery to remove opaque lenses and implant artificial lens
Glaucoma Medications to reduce intraocular pressure, surgery to improve drainage
Eye Injuries Antibiotics, steroids, surgery to repair injuries, treatment specific to type of trauma
Genetic No treatment for eye color itself, manage increased light sensitivity and health risks

The prognosis depends on the specific condition. In many cases, vision can be restored with appropriate veterinary treatment. But the key is addressing the underlying problem quickly before permanent damage occurs.

Outlook for Dogs with Blue Eyes

The outlook for adult dogs with newly blue eyes varies. Some key points about prognosis include:

  • Nuclear sclerosis itself is not harmful, just a normal age-related change.
  • Cataracts, glaucoma, and injuries can often be treated successfully if addressed early.
  • Left untreated, cataracts and glaucoma can lead to permanent blindness.
  • Prognosis is better if only one eye is affected.
  • Smaller opacities that only mildly impair vision may not require treatment.
  • In breeds prone to pale blue eyes, lifelong monitoring for sun damage is needed.

With veterinary treatment tailored to the specific condition, most dogs can retain good vision and live comfortably despite blue eyes. However, regular eye exams are a must to detect issues before they threaten sight.


While startling, blue eyes in an adult dog may just be a normal aging change like nuclear sclerosis. However, acquired blue discoloration can also result from more serious issues like cataracts, glaucoma, trauma or genetics in certain breeds. If your adult dog’s eyes turn blue suddenly, schedule a prompt vet visit for diagnosis and treatment. With early intervention, vision can often be saved. So stay vigilant about eye health monitoring and care.