Cats’ eyes can tell us about a lot of things, from their moods to their overall health. The size of your cat’s pupils can give further insights into what is going on with your cat.
According to Richard Parker, some of the causes include ocular cancer and tumors dysautonomia, poisoning or toxicity, and feline leukemia.
This video demonstrates how healthy cat pupils constrict after dilation. If your cat’s eyes are not constricting, a visit to your vet might be in order.
Can a Cat’s Eyes Stay Dilated Because of Cancer or Tumors?
According to PetMD, one of the most common causes of eye cancer in cats is uveal melanoma. These tumors form in the colored part of the eye known as the iris.
In many cases, these tumors initially start out benign. However, as time progresses, they might become malignant and spread to other parts of the body. The instances of these tumors spreading to other parts of the body may reach 63%
A cat may develop secondary glaucoma in an eye that has one of these tumors. Glaucoma is a condition that causes high eye pressure. Besides interfering with a cat’s vision, this condition may be painful for the cat.
A dilated pupil in the affected eye is one of the most common symptoms, along with changes to the iris’ color, dark spots, an irregular iris, enlarged eyeball, and blindness.
Vets can diagnose this cancer after an ophthalmic exam, with additional testing including a blood panel, X-rays, or an ultrasound. The eye may be removed, depending on the severity of the tumor.
Does Dysautonomia Make Cats’ Eyes Stay Dilated?
According to Vetbook, dysautonomia is a neurological disease that cats develop due to automatic nervous system failure.
Dilated pupils or pupils of different sizes are symptoms affecting the eyes with this condition. Additional symptoms affecting the eyes include ess tear secretion and prolapsed third eyelids. Digestive and heart-related symptoms are also typical.
Cats with this condition have a poor prognosis, with only about a third surviving. Measures such as oxygen therapy, manual bladder emptying, and tube feeding often become necessary for the cat to have the best chances of survival.
When cats survive after this diagnosis, there is a likelihood that their pupils will remain dilated. The less severe the case of dysautonomia, the better the cat’s overall chances of survival. Recurrence of symptoms may happen at a later date.
Is Poisoning Responsible for Cats’ Pupils Being Dilated?
Memphis Veterinary Specialists highlights multiple types of chemicals, plants, foods, and medications poisonous to cats.
However, dilated pupils are not a symptom in most types of poisoning. However, one notable exception is permethrin, an ingredient found in many flea and tick products. These products are designed for dogs but sometimes end up used on cats.
According to the American Association of Feline Practitioners, permethrin is a common cause of poisoning in cats.
How this poisoning happens is when people use products designed for dogs in cats. Although permethrin is a safe ingredient for dogs, it is not safe for cats. Cats often end up ingesting the ingredient during grooming.
Some of the signs of permethrin poisoning in cats include dilated pupils, excessive drooling, anxiety, muscle tremors, and seizures. Cats exhibiting these symptoms require immediate veterinary treatment to prevent life-threatening consequences.
Do Nutritional Deficiencies Cause Dilated Cat Eyes?
According to Patricia P. Scott, cat foods with casein have been linked to Vitamin A deficiency. Pupil dilation in ordinary lighting is common in such cases.
Allivet also cites taurine deficiency as a reason for cats to have dilated pupils. Because the retina is affected, your cat may have difficulty seeing.
Taurine deficiency affects more than the eyes. Digestion issues are also typical, and the deficiency can also affect the cat’s heart. Pregnant females deficient in taurine may give birth to kittens with developmental or growth problems.
Your vet will be in the best position to determine whether your cat is deficient in taurine or other nutrients. Quality cat foods are usually nutritionally complete. However, your vet may direct you to use supplements for your cat.
Can Feline Leukemia Cause Dilated Pupils?
Feline Leukemia is listed as a common cause according to Cornell.
Eye conditions that have dilated pupils as a symptom are common symptoms. Other symptoms include poor appetite and weight loss, gum disorders, persistent diarrhea, and neurological problems. Feline leukemia is diagnosed with a blood test.
Feline leukemia is incurable, but veterinarians can prescribe medications to reduce the severity of symptoms. Most cats die within three years. Cats that have feline leukemia should be kept away from cats that do not have this condition.
Will High Blood Pressure Make a Cat’s Eyes Dilate?
High blood pressure in cats can be a primary or secondary disease. A cat with kidney disease or hyperthyroid can have high blood pressure as a secondary condition. Dilated pupils are a common symptom of high blood pressure.
Vets will check cats’ blood pressure using a cuff suitable for their leg size. Underlying causes of hypertension, like kidney disease or hyperthyroid, can be diagnosed with bloodwork. The treatment depends on whether the condition is primary.
In most cases of high blood pressure as a primary condition, the veterinarian will treat it with hypertension medications like ACE inhibitors. When hypertension is secondary, the vet will also treat the underlying condition.
What Other Issues Cause Cats’ Eyes to Dilate?
There are other things that cause dilated pupils in cats, ranging from behavioral to medical causes. Beverly Bird highlights the importance of making a necessary distinction.
Do your cat’s pupils dilate frequently, or do they remain in a dilated state? The answer to this question may give an indication as to whether your cat’s dilated pupils have a behavioral or physical basis.
If your cat’s pupils constrict in settings with a lot of light, the dilation is something with a temporary cause. Cats’ pupils often dilate because of anger or excitement. Transient dilation is also possible if your cat is in pain.
Hyperactive cats tend to have pupils dilated more often than not. Barring a medical cause for the excessive dilation, your cat may require some calming time. Cats with hyperactive tendencies get overstimulated very easily.
Could a Cat with Dilated Pupils Be in Pain?
Cats have strong survival instincts that motivate them to hide pain as much as possible. When a cat hides the fact that it is in pain, it is not as vulnerable to predators. In many cases, a cat in pain won’t vocalize much because of it.
However, the downside of the cats hiding pain is that they can suffer severe injuries from being in a fight or getting hit by a car without showing any outward signs. Dilated pupils may be the strongest indicator that your cat is injured.
Sometimes, a lasting result of an injury to the head is a condition known as anisocoria. When a cat has anisocoria, one pupil may be larger than the other. This symptom may occur years after an initial injury.
Cats Have Many Reasons for Dilated Pupils
The reasons a cat has dilated pupils can vary from temporary stimulation to medical reasons. Pain can also cause a cat’s pupils to dilate. You will need to determine whether your cat’s pupils constrict or whether they stay dilated.
Following up with your vet when you notice anything unusual with your cat’s health is a good idea. The sooner you get to the bottom of your cat’s dilated pupils, the sooner you can do something about the situation.