Common Causes of Cat Eye Redness

You may have noticed some redness, swelling, or irritation in your cat’s eyes, or perhaps you got scared by a friend’s horror story.

No worries! In this article, you’ll get the lowdown on everything related to keeping your cat’s vision clear and healthy.

This article will cover:

  • Why you should take notice of your cat’s eyes.
  • Symptoms associated with red & irritated eyes (Plus, how to perform an expert-recommended at-home eye exam).
  • Common causes of cat eye redness.
  • How a vet will diagnose & treat your cat.
  • How to prevent redness & irritation in your cat’s eyes.

Not to scare you, but the fact is, redness in your cat’s eyes can be a very serious problem. Not only can it result in surgery and other serious complications, but chronic redness in one or more eyes can be a sign of an underlying health issue.

Plus, because infections are a common cause of redness in the eyes, young cats and kittens can become extremely ill.

However, in most cases where your cat’s eyes appear red, the cause will be likely harmless and the outcome will be minimal.

That being said, it’s extremely important to bring your cat to the vet for regular checkups. It’s just as important to understand what to look for when concerned about redness in your cat’s eyes.

How to Spot Redness in Your Cat’s Eyes

Redness isn’t the only sign your cat has a chronic or acute issue with his eye. Plus, sometimes a bit of redness is hard to spot and knowing some of these other signs will cue you in to take a closer look.

Some of the signs to look for include:

  • Swelling: Along with redness in the whites of the eye, you’ll also likely see swelling. This can be swelling of the eyeball or swelling in the surrounding membranes.
  • Excessive blinking or squinting: No, your cat isn’t winking at you. But he may be letting you know there’s something wrong with his eye. If you notice your cat is blinking or squinting a lot, be sure to perform an at-home eye exam. Not sure how to do it? Read on to the bottom of this section to find out.
  • Holding eyes closed: Along with blinking, your cat may hold his eyes shut. This is usually because of pain or discomfort to the eye.
  • Rubbing or pawing eye: This is often a sign of irritation, sometimes caused by trauma or something stuck in the eye.
  • Excessive tearing: Teary or watery eyes can be a sign of a chronic health condition. Or simply, it may be a way for your cat to try to flush something out of his eye. Either way, keep a close eye (pun intended).
  • Mucus, pus, or discharge: While eye-boogers are normal for cats, excessive or discolored discharge around the eyes is not. If you see this, you should call your vet to make an appointment.

Noticed one or more of these symptoms and want to take a closer look? Read on to the next section to read an expert’s opinion on how to perform at-home eye exams on your cat.

At-Home Eye Exams: An Expert How-To

Examining Your Cat’s Eyes:

  1. The first step is to make sure you’re in a bright, well-lit area. The space should also be clean and familiar to the cat. The last thing you want is your cat getting scared and clawing you while you’re staring into his eyes.
  2. Look at your cat’s eyeballs. They should be clear and bright. The area around the eyeball should be white and the pupils should be equal in size.
  3. With clean, washed hands, roll down your cat’s eyelid using your thumb (remember to be gentle, even when healthy the eye is extremely sensitive). Look closer at the lining of the eyelid. It should be pink, not red or white.

One last thing to watch out for is water or tear-stained patches of fur around your cat’s eye. This could be a sign of blocked tear ducts or tear overproduction.

Common Causes of Cat Eye Redness

So, you found some redness in your cat’s eye and want to find out just what it is. Or perhaps you just want to be prepared in case redness rears its head in the future.

Here’s a carefully selected list of common causes of cat eye redness:

Irritants to Cat Eyes

Just like humans, a cat’s eyes are one of the more sensitive parts of his body. Because of this, a cat’s eyes can become red and irritated due to common irritants in the air.

These can include cigarette smoke, perfumes & air fresheners, pollution, and other chemicals. If your cat has red eyes, think about possible sources of irritants and pollution in your home or apartment.


Similar to chemical irritants, natural allergens can also cause redness in cat’s eyes. In fact, if you suffer from allergies, you may be all too familiar with this symptom.

If it is allergies, that’s generally a good thing, because it means the redness isn’t a sign of a deeper issue. In addition, allergy medication can be easily prescribed.

Foreign Bodies

A foreign object in the eye can cause extreme pain or discomfort for your cat. It can also cause redness, swelling, excessive tears, and abnormal behavior.

Foreign bodies can range from dust particles to much larger objects. Usually, foreign bodies in the eye can be easily treated with minimal recovery down time. However, more serious problems typically occur when left untreated.

Trauma or Injury to the Eye

Many times, redness in your cat’s eyes will be from some sort of trauma or injury. This can simply mean a branch scratched your cat’s eye while climbing a tree, or it can mean he got in a fight with the neighborhood dog.

In most cases, a scratched cornea heals easily, but if left untreated, it could lead to more serious complications.

In some cases, your cat’s eye redness may be caused by “self-trauma”. This is usually from compulsive itching of the eyes. In this situation, you should have your cat wear an Elizabethan collar until symptoms subside.


Infections can be caused or worsened by any of the causes already covered in this article. In other cases, an eye infection is caused by weakened immune systems, an upper-respiratory infection, or another underlying health issue.

Many different types of cat eye infections can affect your cat’s eyes. Usually, along with redness, you’ll see swelling, mucus or discharge, and inflammation.

A common eye infection in cats is pink eye. In cats, just like in humans, pink eye is an inflammation of the light pink lining around the eye. Pink eye is also called conjunctivitis.

Structural Abnormalities in Cat Eyes

There are a few structural abnormalities of the eye and surrounding area that can cause issues in cats.

Two of these are entropion and ectropion. Entropion is when the eyelids begin protruding inwards.

This can cause irritation because the eyelashes are constantly rubbing against the eyeball. This is also true of ectropion, though ectropion is where the eyelashes curve the other way.

Structural abnormalities can lead to huge issues including blindness. Make sure to get these checked out by y