Why Are My Cats Eyes Always Dilated.

Why Are My Cats Eyes Always Dilated. The pupils of cats’ eyes may dilate when they are afraid, happy, or in pain.

Because cats’ pupils widen in low-lit areas, this means their vision at night is typically much better than their human oawners.

However, except for kittens who are much more sensitive to light and need a lot of rest and sleep, over-dilation of the pupils can signify a vast number of health concerns such as disorders related to the autonomic nervous system.

Where imbalance prevents eyes from relapsing back to normal size and Toxoplasmosis which is often caused by cleaning an infected litter box.

Why Are My Cats Eyes Always Dilated

It can be very worrying to see your cat’s eyes dilated, so much so that you may find yourself rubbing the corners of their eyes in an attempt to get them to change shape. However, it’s important not to make a move like this as it could cause them discomfort and stress when there are more serious health concerns to be taken into consideration such as feline leukemia or Leukaemia, toxicity, and even dysautonomia.


Dilated pupils in cats are often down to certain medical conditions such as hypertension. Hypertension is not uncommon in older cats or when obese, though it’s difficult for veterinarians to diagnose.

Symptoms of high blood pressure include dilated pupils whose dilation does not adjust to bright light so these dilated pupils may be the key sign to let you know that your cat has this medical condition.

Left untreated, other symptoms of hypertension can lead to major problems including a detachment of the retina, leaving your cat blind.

Types Of Pupil

In the past, cats were nocturnal animals that fed in the dark to avoid predators. Although this behavior has naturally regressed since there are not so many predators around these days like.


when our cats’ ancestors roamed the earth, cats eyes still dilate for night vision an adaptive trait that has been created by evolution over time as a survival instinct!


It is not a voluntary act similar to an eye-blink but a natural reaction that develops based on certain stimuli, such as low light or advanced age when the sense of sight becomes weaker.

Anxiety Disorder

Another reason why cats have round pupils is that they are scared when suddenly surprised, as it is a natural response for a cat’s eyes to dilate.

This may happen if there is a sudden loud noise that startles your cat or the presence of an unknown person or animal.

However, if your cat’s eyes are constantly dilated because of fear they may suffer from anxiety and be on edge. Sustained periods of high stress can trigger other problems including aggression or loss of appetite.

Uneven Pupils

Unilateral pupil dilation could be due to injury to the ophthalmic nerve or the brain itself since it is the entity that innervates both the left side and right side of each eye.

But, if we consider a closer look at anisocoria, another cause for this particular condition could be a neurotropic disease affecting the preganglionic parasympathetic cell bodies in one of the three chains innervating the pupil known as Horner’s syndrome.

Poor Vision

It is possible to confuse cataracts with retinal detachment. Both may lead to his symptoms listed above and both are different in terms of how they present.

Cataracts present more suddenly than retinal detachment and will cloud your pupil’s vision rather than make it appear as though the pupil is dilating when looking at the affected eye.

Both can be treated in a similar way with prescription medication given to you by your veterinarian.

Final Words

Although it is healthy for a cat to have its pupils dilate as they react to changes in the environment if your cat’s eyes always stay dilated there may be an underlying illness causing this. Usually, hypertension is responsible for the onset of permanently dilated pupils because it is usually a secondary condition.

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