BetterWithCats.net may earn a small commission when you use one of the links on this page to purchase.
I can definitely admit that I’ve spent much of my time looking into my cat’s beautiful eyes, noticing how the shades of yellow and green create a unique pattern.
If you’ve had a cat since they were a kitten then you might have noticed a significant change in hue and color as they grew older, or perhaps you’ve noticed that the color of their eye suddenly changed during adulthood and you’re wondering if this is normal.
Why do my cat’s eyes change color?
Kittens are usually born with blue eyes, but between 4 to 10 weeks the production of melanin could turn their eyes into another color. If your cat’s eye color changes when they’re older then this is likely caused by eye trauma, disease, or a normal part of the aging process in some cases.
Let’s take a closer look at the reasons your cat’s eyes might be changing and the possible dangers lurking behind this sudden color transition!
Why Do Kitten Eyes Change Color?
Before we talk about older cats going through eye color changes it’s important we go back into their kittenhood.
During the first weeks of a cat’s life, they’re very fragile not only due to their small size but the fact that they are born with their eyes closed and without the ability to hear. Thankfully cats develop quite quickly and between 8 to 12 days their eyes will begin to slowly open.
No matter what shade of color your cat’s eyes are now, all kittens are born with baby blue eyes, and as veterinarians explain at 7 weeks of age their eyes will change to an adult eye color. At 8 weeks of age, your cat’s eyes will have evolved into the color that they’ll have for the rest of their lives. Some cats will maintain their blue eyes, or they might transition into shades of green, yellow, orange, copper, and hazel.
I know it’s hard to imagine that this copper-eyed kitty used to have blue eyes as a kitten!
This change happens during the developmental period, and just like in human eyes, the color of the eyes depends on how much pigment melanin there is in the iris. This protein releases cells called melanocytes and it is the same cell that also affects their skin and fur.
The more pigment there is the darker your cat’s eyes will be, which means that blue-eyed cats have very little to no melanin. Just like with fur, the color of a cat’s eyes depends on the genetics that are passed on to the cat from their parents.
Unlike their fur or our human eyes cats don’t develop dark colors like brown or black, the darkest color a cat can possess is a deep, rich copper. So, if you noticed that your kitten’s eyes changed color as they grew older then it’s most likely caused by this complicated process.
Of course, since kittens are in need of attention and monitoring, the safest option would still be a vet appointment, so you can make sure their eye color is the result of this natural change and not a medical condition.
Why Do My Cat’s Eyes Change Color?
Once your kitten’s eyes stop developing, especially once they’ve reached adulthood, their color becomes permanent and unchangeable. If you notice that your adult cat’s eyes changed color in any way, it’s a serious cause for concern.
Such changes are usually the result of a medical issue caused by trauma, or disease.
It’s A Health Issue
Let’s take a look at some of the common causes that can affect one or both eyes and cause the color of your cat’s eyes to change.
1. Corneal Ulcers
A condition that could affect your cat’s eyes and change the way they look is corneal ulcers. To be more specific ulcers affect the cornea, the glistening and transparent membrane that make up the surface of the feline eyeball, and can make it appear cloudy or milky and red.
Since there are three layers in the cornea penetration or erosion through the first two layers is called corneal erosion or corneal abrasion while a corneal ulcer is much deeper, reaching the final layer.
Ulcers are most commonly caused by a deeper trauma, specifically blunt trauma and laceration that usually occur during catfights. Additionally, your cat might end up rubbing their eye too much if a piece of dirt, any sharp foreign object, or an ingrown eyelash ends up beneath the eyelid.
A less common but still possible reason is a chemical burn of the cornea from toxic liquids like cleaning products and shampoos. Even a strong laser pointer could damage your cat’s eyes since they’re six times more sensitive than humans eyes are. Other ways your kitty could end up with ulcers are viral or bacterial infections, as well as conditions like diabetes mellitus, and Cushing’s disease.
According to Thomas Kern, DVM, the most frequent cause is recurrent infection with the feline herpesvirus (FHV). The virus could attack the surface of the eye and cause ulceration.
Aside from the change in your cat’s eye color or appearance, corneal ulcers is very painful that’s why:
- Your cat will most likely rub the affected eye causing more problems.
- You’ll also notice them blink rapidly, squint, or even keep the lids tightly closed.
- Discharge might collect in the corner of the eye or run down the face.
- You’ll also typically notice a change in only one eye.
It’s not easy to know how badly damaged the eye is, and whether it’s ulcers or an abrasion. But no matter the depth of the trauma, you still need to take your kitty to the vet. Thankfully Corneal ulcers are easy to detect with the use of fluorescein stain, an orange-colored stain that will turn the damaged area green.
By taking your kitty to the vet you won’t simply get a proper diagnosis, but a suitable treatment to help heal the eye and stop any permanent damage that could result in loss of vision.
2. Bacterial Infections
Trauma isn’t the only way your cat’s eyes can be affected, bacterial infections and viruses can also be responsible. Some of the most common infectious conditions that can lead to eye infections, according to Memphis Veterinary Specialists, are the feline viral rhinotracheitis and feline calicivirus.
These upper respiratory diseases are highly contagious among cats so you might find both your cats’ eyes turn red, they might squint or wink repeatedly. Even mild eye infections caused by allergies can lead to a corneal ulcer if your kitty keeps rubbing at their eyes.
That’s why any signs of intense blinking, redness in the eye or around it are reasons enough to take your kitty for a check-up!
According to veterinarians, entropion is a “genetic condition in which a portion of the eyelid is inverted or folded inward against the eyeball. This results in irritation and scratches to the cornea.”
While this condition may not clearly change the color of your cat’s eyes you might notice at its early stages a visible redness caused by irritation. One of my cats had a serious issue with his eyes. I first thought was an allergic reaction to some plants he had rubbed against.
The third eyelid was inflamed because my kitty was constantly rubbing at his eyes, in the space of a few hours they had turned really red, and the eyelid became puffy and inverted to the point that he couldn’t keep them open.
Of course, my vet realized that my cat had Entropion that usually is diagnosed around the time a cat reaches their second year of age. She tried everything she could to help my kitty’s eyes. Plenty of medicine and a blepharoplasty later my kitty’s eyes were their normal yellow color, shining bright and looking curious as always.
To this day I keep an eye on his eyes, look for signs of redness, squinting and discharge.
While this condition can be caused by some infections, even ulcers, it’s commonly caused by genetic predisposition and if your cat’s breed is known to be affected by entropion, make sure you talk to your vet and monitor their eyes to prevent serious damage.
If you notice your cat’s eyes have turned red, including the white part of the eye then it could be Uveitis. This condition is the inflammation of one or more of the structures making up the uvea, which includes the iris, the middle layer of the eye, and part of the wall of the eye.
Uveitis might only affect one of your cat’s eyes but it could affect both at the same time. What causes this condition can vary. Infections, including feline leukemia (FeLV), feline immunodeficiency virus (FIV), bacterial parasitic like toxoplasmosis, or fungal.
High blood pressure, as well as diabetes, can be responsible, or uveitis might be the result of an autoimmune disease. Trauma and eye tumors could also cause this condition, but sometimes the true cause might never be discovered.
Just like the previous conditions, Uveitis causes:
- Pain and some cats will try to rub it or avoid touching it.
- Prominent redness.
- Your cat might squint or blink spasmodically.
- Bright lights avoidance.
According to Ryan Llera, DVM, “usually there is a clear watery discharge from the eye, but in some cases, there may be mucus or pus.” They also add that “If the anterior uvea is involved in the inflammation, the eye may appear cloudy.”
Chronic uveitis can also result in iridal swelling, making the pupil appear irregular and it won’t respond to light appropriately.
The eyes are definitely one of the most sensitive organs and veterinarians warn that uveitis must be treated aggressively if you want to prevent glaucoma. So, any changes in your cat’s eye color or overall appearance should be enough of a sign to take make an appointment with your local pet clinic.
Another serious condition that affects the cat eyes is cataracts. According to Cornell University “A cataract is a condition in which the lens becomes cloudy or totally opaque. When this happens, incoming light is impeded, if not totally prevented, from passing through the eye to the retina.”
If you notice that your cat’s eyes have become cloudy or milky-gray it could be cataracts. While in some cases the affected area of the lens may be small, in other cases it may include the whole lens causing total blindness, in one or both eyes.
Once again, intense eye trauma or exposure to toxic substances can lead to cataracts. Diabetes and hypertension could also be responsible and for some cats, it’s the result of the aging process.
Cataracts is diagnosed by your cat’s eye appearance and the loss of vision. Apart from the change in your cat’s eye you may notice them become less agile, bump into furniture, and having difficulty finding their litter box or food and water bowls.
Early diagnosis and treatment of underlying issues like high blood pressure or diabetes will help slow the progression of cataracts. In some cases, surgery might be the only option. Dr. Kern, DVM, notes that “the procedure is successful in most kittens and mature cats that have qualified as good candidates for lens implantation.”
Feline Glaucoma as it’s described by the Cornell Feline Health Center, “is a condition in which the watery fluid (aqueous humor) contained in the front part of the eye, just behind the lens, is unable to drain normally. The resulting accumulation of this fluid puts pressure on the optic nerve, which leads from the eye to the brain.”
This pressure can cause nerve damage and prevent normal vision. If left untreated it can lead to partial or total blindness in one or both eyes. The most common cause of glaucoma according to Dr. Kern is uveitis, the severe inflammation that we’ve discussed above.
Tammy Hunter, DVM, points out the common signs and symptoms of glaucoma include:
- Your cat might start avoiding your touch near the side of their head because of the eye pain, and they might rub the affected area, or keep their eye closed.
- Physical swelling and bulging of the eyeball.
- The white of the eye might look red, or bloodshot and swollen.
- The cornea or clear part of the eye may become cloudy or bluish in color.
- The eye might appear darker because of the dilated pupil.
- Watery discharge coming from the affected eye or eyes.
- Behavioral changes like looking depressed, hiding, and being unresponsive.
- Blindness can happen quickly unless the pressure within the eye isn’t reduced.
The pressure from the fluid needs to be reduced as soon as possible, so if you notice any changes in your cat’s eyes color or any of the above signs it’s important to get them to the vet for a checkup.
Of the most common feline eye disorders is Conjunctivitis. “It’s the inflammation of the thin mucous membrane that lines the inner surface of a cat’s eyelids and coats the outer surface of the eyeball,” explains the Cornell Feline Health Center.
This membrane plays an important role, Dr. Kern, DVM, points out, since it’s a conduit for tears that fall into its surface and is distributed by your cat’s blinking. Most importantly it contains certain antibodies that help ward off some eye infections.
Basically, your cat’s own immune system can react to certain microorganisms, bacteria, and viruses they commonly carry and cause conjunctivitis.
The major changes in your cat’s eyes that you will notice include:
- Squinting and constant blinking.
- Discharge coming from the eye can be colorless and watery or thick and dark-colored, yellow or greenish.
- The third eyelid might become swollen and look red.
- Sensitivity to bright light
There are various things that could cause this condition, Tammy Hunter, DVM, divides them into two categories, “infectious diseases and non-infectious conditions including allergies, hereditary conditions, and tumors.”
So, from environmental irritants like dust, airborne chemical substances, and certain plants, to entropion that’s common in Persians and Himalayan cats. Usually, though, conjunctivitis is caused by, herpesvirus, the calicivirus, or one of two bacteria—Chlamydophila or mycoplasma. Cats with a compromised immune system from FIV or FeLV are also susceptible to it.
Icterus or best known as Jaundice is caused by liver disease, destruction of red blood cells, or obstruction of the bile duct. There are ways to detect this condition as it causes the accumulation of a yellow pigment in the blood and tissues.
That’s why you might notice the white part of your cat’s eye turn yellow, as well as the gums and ear flaps.
Other symptoms of Jaundice may include:
- Vomiting and diarrhea
- Lethargic state and mental confusion
- Abdominal pain and loss of appetite
- The color of their urine and feces will turn orange
- Increase thirst and urination
Malcolm Weir, DVM, states that “Icterus is not a disease; it is a clinical sign indicating that an underlying disease is present. When the underlying disease is diagnosed and treated successfully, icterus will resolve.”
That’s why if you feel that your cat’s eyes look yellow, and they overall seem unhealthy make sure to make an appointment to find out if Jaundice or another disease is causing it.
9. Portosystemic Liver Shunt
The liver is one of the most important organs in a cat’s body, in fact, Dr. Goldstein, DVM, calls it “the guardian of a cat’s body.” Some cats he explains are born with a defect called portosystemic shunt.
What happens is that toxins that enter the cat’s body aren’t going to the liver to go through proper detoxification, instead, the portosystemic shunt, an abnormal vessel, diverts the blood directly to the heart.
It has been reported that the irises of both eyes in cats with this condition turned copper, but this symptom alone isn’t enough to rely on in order to diagnose your cat with portosystemic shunt.
Most common symptoms show:
abnormalities in the digestive system among them vomiting, diarrhea, and diminished appetite.
- Temporary blindness.
- excessive salivation.
Since this condition can be congenital or acquired later in life, checking your cat’s eye color and health overall is a must.
10. Eosinophilic Keratitis
Another condition called Eosinophilic Keratitis can make your cat’s eyes appear pink, white, or grey. This is a chronic, inflammatory disease that happens when a type of white blood cell invades the cornea, the undersides of the eyelids, and the white of the eye.
Catherine Barnette, DVM, states that this disease usually “involves an allergic reaction as well as the body’s immune reaction to parasites.”
While veterinarians don’t exactly understand the cause, they’ve observed that 75% of cats that have feline herpesvirus have eosinophilic keratitis.
“Owners may notice that there are new blood vessels forming at the edge of the cornea, soon followed by a white/grey film that develops on the surface of the cornea,” Barnette explains. “Chronic lesions may sometimes develop a gritty texture, due to calcium deposits within the lesions.” She adds.
This disease needs to be treated as soon as possible because it can easily lead to other infections, which can cause permanent damage and even blindness.
11. Corneal Sequestrum
Corneal sequestrum is a piece of the cornea that has died off and is rejected by the remaining healthy cornea. It produces brown to black plaques of dead tissue on the cornea and takes on a brownish discoloration.
This is a painful condition, and you will notice your cat’s affected eye become sore as the corneal sequestrum is being rejected by the healthy cornea. Not only does this mean that your cat’s affected eye is more prone to infection, but there may be visual impairment as well.
The change in your cat’s eye appearance and color will also be followed by tearing and squinting.
This condition is most common in short-nosed cats, like the Persian, the Burmese, and the British Short-Hair. But it could also be the result of chronic corneal trauma the kind that is common in cats with entropion, as we’ve mentioned above.
The Eye veterinary clinic also points out that corneal sequestrum might develop after an especially serious episode of cat flu due to the Feline Herpesvirus.
If your kitty is suffering from corneal sequestrum they’ll need medical treatment and surgical intervention. To be sure what has caused your cat’s eyes to change color, you should check with your veterinarian and see what your best options for treatment are.
12. Lenticular Sclerosis
Finally, another reason you might find your cat’s eye color changing is a condition called lenticular sclerosis or nuclear sclerosis.
You’ll notice a bluish haze develop in the lens of the eye and it’s mostly associated with aging. While the mechanism isn’t completely understood, what happens is that the lens becomes harder with age.
Thankfully the vision isn’t usually affected significantly, and this condition shouldn’t be confused with cataracts. As we’ve discussed above cataracts creates a white opaque layer and the light can’t penetrate the retina, thus diminishing the vision.
Lenticular sclerosis usually begins when a cat is eight years old and is more observable in cats over nine years old, Tammy Hunter, DVM, explains:
“Lenticular sclerosis appears as an evenly gray, rounded opacity (cloudiness) in the center of the lens. It is most easily observed when the pupil is dilated. The opacity is often more dramatic when viewed from the side rather than from the front.”
Cataracts and lenticular sclerosis aren’t related but some cats with lenticular sclerosis might develop cataracts later in life. Unfortunately, there’s no specific treatment for lenticular sclerosis, that’s why it’s important that your vet regularly monitors your cat’s eyes in case they develop cataracts, which can be treated if diagnosed early.
What Are They Types Of Colors A Cat Can Have?
While all kittens are born with beautiful baby blue eyes, many of them will change and there’s a range of different colors they might turn into. Your kitty’s eyes might change into a beautiful shade of green, yellow, orange, and blue. All of these colors might turn out to be a darker or a lighter shade.
Some cats might end up having a rare combination of two different eye colors or each dichroic eye, where each eye has a combination of two different colors within the eye.
Melanin is what determines the color of your cat’s eyes, as well as their fur coat. The more melanin the darker the eye and a rich copper is the darkest eye color they can get.
Certain breeds are more likely to have particular colors, and purebred cats are bred to meet specific breed standards. For example, the Bombay cats are known for their black coats and googly copper-colored eyes.
Havana brown on the other hand are loved for their rare chocolate coat and contrasting green eyes. If you’ve ever had a Siamese kitty then you know that one of their most notable features are their deep blue eyes that glow intensely red in the dark.
For more information about this topic, read our cat eye color chart.
Can Cat Eyes Change Color With Age?
As we’ve discussed at the very beginning, only a kitten’s eyes go through a drastic change where they can turn from blue to amber. Once the kitten is older their eyes remain the same. Of course, as a cat grows older, there might be a slight shift in the shade and detail of the color, just like in humans.
Nonetheless, even a slight shift in hue should be enough for you to take your kitty to the vet. If they’ve acquired a blueish haze then it could be the sign of lenticular sclerosis as we’ve discussed already. Dr. Marty Becker, DVM, states that “this condition is a result of the normal aging of the lens of the eye. New fibers form on the surface of the lens, and the lens starts to lose moisture as the years go by.”
Where your cat has lenticular sclerosis or not, senior cats need regular checkups and increased attention to their eyes. Older cats are more likely to develop cataracts, conjunctivitis as well as glaucoma. Sudden or graduate blindness is also something senior cats have more chances of developing.
While leaving a light on for a young cat might sound silly, Dr. Levine states that “nightlights help older cats with poor vision or eyesight problems navigate at night.” Many of the conditions we’ve mentioned above also cause light sensitivity so try not to turn the bright lights on until your kitty’s eyes are healthy again and back to their normal color if that’s possible.
A lot of things might change as your cat ages but if that change has affected their eyes then you definitely shouldn’t let it go unchecked.
Why Does My Cat Have Two Different Colored Eyes?
As your kitten grows older you will notice their eyes change, and there’s a possibility that they’ll end up with two different eyes, also known as heterochromia.
Odd-eyed cats will usually have one blue eye and one eye either yellow, green, or brown and this condition usually affects white cats. Cats that aren’t white can also have two different colored eyes as long as they have the white spotting gene.
This specific white spotting gene or the epistatic (dominant) gene, prevents melanin from reaching one of the two eyes during development. So basically, your kitty retains one baby blue eye, while the odd eye transitions to another color.
This isn’t something that should necessarily worry you, but if your kitty is white and they have odd eyes they might also be deaf in one or both ears. This genetic defect is called congenital deafness.
Just look at this odd-eyed, snow-white beauty that doesn’t realize how loud she is because of her deadness!
So, if you think your beautiful odd-eyed kitty sleeps very soundly, doesn’t react to you calling them or any loud noises then they might be deaf. In this case, you might want to work on how you communicate with your deaf kitty in a way that can help them feel safe around you and their surroundings.
Why Is My Cat’s Eye Darker Than The Other?
Pupils respond to changes in the light conditions, as it gets darker you might notice your cat’s pupil grow larger and if it’s really dark, they can almost make the iris disappear. By expanding the pupil your cat can see better at night, so it’s nothing to be worried about.
However, if you notice that your cat’s eyes have turned black regardless of the light conditions then most likely there’s a medical issue at play.
Cats are cautious creatures, but that doesn’t mean they can’t get hurt. If your kitty is living outdoors, then it’s more likely that they may injure their eyes.
This can happen if they’ve been running through heavy vegetation like thorned bushes. Fights with other animals especially other cats can also easily leave your kitty with an eye injury since their fighting style includes clawing and scratching at each other’s faces.
But not only outdoor cats can end up with a serious corneal injury. Young cats that haven’t learned how to be cautious can end up hurting themselves by accident, even in the safety of our home.
According to veterinarians, common symptoms of corneal lacerations are:
- Blood in the eye will make it appear darker.
- There could be a foreign object in the eye that’s easy to see.
- Your cat’s pupil might look distorted.
- The cornea might look clouded.
- The eye is protruding.
Depending on the trauma your cat’s eye has sustained your vet will suggest a certain treatment or even surgery. That’s why the moment you see your kitty’s eyes look darker you need to take them to the veterinarian. The more you wait the more your kitty will rub their eye and cause more trauma.
Another reason why one or rarely both of your cat’s eyes might appear darker is Horner’s Syndrome. The ScienceDirect, explains that “Horner’s syndrome results from loss of sympathetic innervation to the eye and is characterized by miosis, ptosis, enophthalmos, and protrusion of the third eyelid”.
There are different causes that can lead to this condition, like trauma in the areas of the neck, ear, and the eye itself. Inflammation of the nerves in these areas, middle ear problems, as well as tumors of the spine, chest, or brain.
If your kitty is suffering from this Ryan Llera, DVM states that the clinical signs of Horner’s syndrome include:
- You might notice the upper eyelids on the affecter eye drooping.
- The third eyelid might look red, raised, or protruding.
- The pupil will look constricted or smaller than usual, which can make the other pupil appear larger.
- The affected eye’s pupil will look sunken.
Usually, cats affected with this condition will heal on their own over time, but Llera still suggests that you need to take your kitty to the vet for further examinations. Even if Horner’s syndrome will resolve itself your kitty might still need medications or certain treatment to avoid injuring the affected area.
If you discover that your cat’s eye looks black or darker than usual, then it could be a melanoma in the iris.
Iris melanosis is a type of cancer that develops from an over-proliferation of melanin in your cat’s eyes. It usually starts small, but it can progress over time. Usually, iris melanosis itself is a benign condition, but it needs to be monitored closely since it can still develop into a malignant condition.
Debbie Stoewen, DVM, states that iris melanoma may appear as one or more freckles on the iris. They might look round, irregular, or streaky in shape. While they might start off as brown spots, they usually turn very dark brown and as they grow, they end up overlapping, making the iris look darker.
By monitoring your cat’s condition, you can prevent other eye diseases to take over. The progression of this condition varies as well, so you might have to look into certain treatments and even surgery.
Why Do Cats’ Eyes Color Change At Night?
Whether it’s the spooky season or not seeing your cat’s eyes glow red or green in the dark can send shivers down anyone’s spine. The reason they look so different during the night has nothing to do with color change, in fact, your cat’s eyes stay the same whether there’s light or not.
You see cat eyes are built differently than ours. They are crepuscular animals, meaning that they are most active at dawn and dusk. That’s why they need a good night vision to hunt in this half-darkness.
Cats have six to eight times more rod cells than us that are sensitive to low light. Their eye shape and larger corneas and the fact that they can dilate their pupils completely also mean that they can let more light enter their eyes.
But all of that doesn’t make their eyes glow in the dark, the structure behind the retina, called the tapetum is responsible for that. The tapetum acts like a mirror reflecting the light that passes between the rods to the photoreceptors.
While this glowing effect may seem eerie, since it may appear that your cat has no iris or pupil, especially if you find your kitty staring at you while you were asleep, but once you turn on the light the red glow will disappear and everything about your cat’s eye will be back to normal!
What Should I Do If My Cat’s Eyes Change Color?
Noticing that your kitten’s eyes are no longer blue, can come as a surprise, but most likely it’s a natural change their eyes go through as they grow older. If you feel that the change seems unnatural, the eyes look red, or puffy then it’s best you take the kitten to the vet.
Even if your kitten’s eye color change turns out to be this normal process I still think the visit to the veterinarian was worth it. Kittens are resilient but they can also be fragile so an extra vet examination will never hurt!
If on the other hand, you’ve found that your adult cat’s eyes have changed color, or shade then once again a vet visit is the best choice. A variation in your cat’s iris color could be a sign of illness, that goes way beyond their eyes, or it could be a serious eye infection.
The sooner you take your cat for an examination you can help your vet treat a possible life-threatening medical condition or simply ease your cat’s discomfort from a superficial eye scratch. Self-diagnosing is never a good choice because a professional knows the best and safest ways to ensure that your cat’s eyes are healthy!
It’s said that the eyes are the windows to the soul and there is definitely something magical when we gaze into the mystical eyes of our feline companions.
But the important lesson you need to take from this article isn’t only that your cat has beautiful eyes, but that they should never change. While it can happen to kittens, adult cats will keep the same eye color for the rest of their lives, and if you spot a change don’t hesitate and call your vet or pay them a visit!
So, tell us what color did your cat’s eyes turned out to be when they grew up? Did they stay blue or changed into something darker?
Read Next: Why Is My Cat Thin At The Back End