As a doting cat owner, you've likely cleaned some "gunk" out from your beloved feline's eyes at one point or another. Like people, cats can experience eye discharge that may affect them in varying ways.
Typically, a small amount of eye discharge from time to time isn't something to be terribly concerned about. However, if the discharge is long-lasting or chronic, it can be a sign of disease or infection that you'll need to address in a timely manner.
In this article, we'll cover the reasons for your cat's eye discharge, what it could potentially mean, and what to do next. Let's begin!
What is Cat Eye Discharge
Generally, eye discharge is not a disease itself, but rather a sign of an underlying condition. Many diseases for which eye discharge may be a sign can progress to blindness and/or systemic infection.
Therefore, if the discharge is chronic, experts recommend that you let your veterinarian take a more thorough look into exactly what may be causing it.
Simply speaking, cat eye discharge originates from the tears that the body constantly produces throughout the day.
Usually, the tears drain at the corner of the eye without spilling over. However, when something irritates the eyes, the body produces more tears than normal. This results in a discharge from the eye that is much more pronounced than usual.
Furthermore, while eye discharge may not have a highly negative effect on many people, it can cause your cat a great deal of discomfort.
From constant scratching to milder itchy sensations to overall eye pain, if your cat is experiencing chronic eye discharge, you'll want to get to the bottom of it.
Signs of Eye Discharge in Cats
The physical signs of eye discharge in cats are comparable to the symptoms that you may experience yourself.
Cat eye discharge can vary in how often it occurs, its consistency, and how badly it irritates your four-legged friend.
First, you'll likely find a watery discharge around your cat's eyes. If you feel the surrounding fur, you'll be able to feel the wetness.
The moisture can range from being thin to thick in consistency.
Eye Boogers | Eye Mucus
Also, you may find sticky clumps around your cat's eyes. Many pet owners refer to these as “eye boogers.”
The substance typically has a thick mucus-like consistency, but the amount of discharge will often vary based on the severity of the infection or illness that’s affecting your cat.
You'll also commonly find crust formation around your cat's eyes. This indicates dried eye discharge. A small amount of crust from time to time is usually normal.
However, if you notice large amounts of crusty matter, then you can assume there was a large amount of discharge or mucus, which typically indicates the presence of eye problems.
Red, Swollen, Squinting Eyes
Watery eyes are often accompanied by physical signs such as redness and swelling. This is a clear indicator of some form of infection or ailment, and is definitely abnormal.
You'll also find that cats with red, swollen eyes constantly rub their faces on anything from the couch to your pants, all in an attempt to relieve the itch and irritation.
Causes of Cat Eye Discharge
While an occasional eye discharge is usually not something to worry about, chronic discharge certainly is. Again, cat eye discharge in itself is not a disease, but rather a sign of a condition that may need professional treatment.
Several of the ailments that we are about to discuss can result in blindness. Furthermore, it is entirely possible for an eye infection to spread and affect other parts of the body.
It is imperative that as a cat owner, you remain aware of the normal amount of eye discharge, so in cases of abnormalities, you are able to act accordingly.
Feline Upper Respiratory Infections
One potential cause of excessive eye discharge is an upper respiratory infection. This includes infections caused by:
- Feline calicivirus
- Rhinotracheitis (herpesvirus)
- Other contagious respiratory conditions
You may not think that your cat has an upper respiratory infection because signs can start off very mildly and remain that way for an extended period of time before they quickly worsen and become quite severe.
Eye discharge associated with an upper respiratory infection is often sticky and resembles pus. Upper respiratory infections will also show signs such as nasal discharge and sneezing.
Conjunctivitis (Pink Eye)
When you trace the vast majority of ailments back to their root, you'll find that they often have one major thing in common: inflammation. Conjunctivitis, also known as “pink eye,” refers to inflammation of the light pink lining around the eye.
Conjunctivitis will cause your cat's eyes (either one or both) to appear swollen and red. In such cases, your cat will commonly be sensitive to light, and the discharge can be clear and watery, or a thick mucus around the affected eye(s).
Most cases of conjunctivitis can be resolved in a timely manner without permanent damage to the eyes. However, in some cases, conjunctivitis is accompanied by diarrhea, fever, and trouble breathing, and this may be indicative of a more serious condition, feline infectious peritonitis, which can be fatal. If you notice any of these signs, please ensure your cat sees the vet ASAP.
Excessive eye discharge in cats could also be due to a corneal disorder. The cornea is the rounded surface that covers and helps to protect the front of the eye.
Unfortunately, the cornea can become injured, inflamed, or ulcerated more easily than you may think.
As a result, the body automatically produces more tears, which can cause excessive blinking, cloudiness, inflammation and irritation, and eye discharge.
Cat Eye Infections
Eye problems that are linked to an infectious agent, such as bacteria or a virus, are fairly common in cats.
Eye infections can also be extremely contagious and quickly pass from one cat to another. Therefore, if you believe your cat might have an eye infection, proper treatment in a timely manner is imperative.
In younger cats and kittens, Chlamydia and Mycoplasma are two bacteria that are most often responsible for eye infections. The viral infections are typically caused by feline herpesvirus type 1 and feline calicivirus.
Young cats typically have weaker immune systems and their bodies are not yet equipped to fight off the bacteria or virus, thus making them more prone to an infection.
Furthermore, young cats that are exposed to environments with a high population of other cats, such as at shelters, are also at a much higher risk of contracting an eye infection.
In older cats living in controlled environments (i.e., not strays or older cats in shelters), eye infection may be considered a secondary ailment to a pre-existing condition.
Autoimmune disease, eye trauma, cancer, and systemic viral infections like feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) could also lead to the development of an eye infection.
Regardless of age, all cats with a bacterial or viral infection of the eye must be treated appropriately. These infections can be highly contagious and are difficult to control in crowded environments.
Bacterial infections will often need antibiotics. Therefore, the sooner you are able to receive a proper diagnosis, the sooner you can begin treatment and prevent the spread of the infection to any other pets.
Epiphora (Watery, Tearing Eyes)
The term epiphora is defined as excessive tear production. You may hear your vet refer to your cat's eye discharge as such, however, it is important to determine exactly what is causing the excessive tearing.
Tearing, watery eyes can also be the result of conditions like:
Blocked Tear Ducts
Often, an upper respiratory infection can lead to blocked tear ducts, which can often lead to an excessive amount of discharge, as the body naturally attempts to clear the blockage.
An Overproduction of Tears
This is often the result of an injury or infection. Again, the body is naturally trying to rid the eye of any foreign object or infectious agent.
Like people, cats are also prone to allergies, which often result in signs like teary eyes, a runny nose, and irritation of the respiratory system.
Allergic reactions can occur from a multitude of sources, including pet food, medications, environmental allergens, household plants, and chemicals like herbicides and pesticides.
If your cat is having an allergic reaction, they may also exhibit signs like vomiting and diarrhea.
Each of these conditions can lead to epiphora, and will necessitate different, specific treatment, all which we will discuss momentarily.
Keratoconjunctivitis Sicca (Dry Eye)
While epiphora is the overproduction of tears, keratoconjunctivitis sicca is the underproduction of tears.
If the eye(s) experience chronic or long-lasting dryness, the result is almost always inflammation of the cornea, redness, and considerable irritation and pain.
If left untreated, keratoconjunctivitis sicca can result in blindness. Cats experiencing chronic dry eyes will often have a yellow, sticky discharge.
Eye drops, other medications, and sometimes surgery are necessary to help stimulate tear production and to restore the tear film.
Keratoconjunctivitis sicca is an eye condition that should not be ignored, as it can have horrific, irreversible side effects.
Uveitis refers to inflammation of the uvea, or internal structures of the eye. A number of conditions can lead to this condition, including physical trauma, various eye cancers, problems with the immune system, and various infections.
Feline uveitis is a common and painful ocular disease that will require appropriate veterinary treatment. If left untreated, this condition can result in blindness.
Foreign Object in the Eye
Cat eye discharge could also be caused by a foreign object in the eye. This will often result in the natural overproduction of tears in an attempt to get rid of whatever is causing the irritation.
In many cases, the excessive production of tears could successfully get rid of the foreign body. However, if the foreign object is lodged in the eye, a veterinarian will have to step in.
If your cat enjoys playing outdoors, or is particularly curious and suddenly seems to have eye problems, a foreign object might be trapped in the eye. Please visit the vet if you suspect that might be the case.
Additionally, outdoor cats and those that love to explore are at a higher risk of eye injuries. The eye can be very fragile and is not designed to withstand the trauma of harmful branches or the claws of another animal.
If you have an outdoor cat, it is important to take note of their eye health. Certain eye injuries can become worse over time and lead to infection if left untreated or if the injury is severe.
Certain breeds are at a higher risk of developing eye problems and thus, excessive eye discharge due to the shape of their faces.
Breeds such as Persians, Himalayans and other brachycephalic cat breeds (those with relatively large eyes and short noses) are more prone to excessive tear production.
With these breeds, it is important to know your cat's "normal." This will ensure that you are able to recognize when something isn't normal and act accordingly.
When to Go to the Vet
We want to reiterate that while a relatively small amount of discharge from you cat’s eyes can be considered normal from time to time, no amount of excessive discharge should be considered normal, regardless of the color or consistency. However, there are certain cases for which a trip to the vet is imperative.
If you notice a yellow or green discharge, make an appointment straight away, as it is a telling sign of infection. Additionally, if there is enough discharge that needs to be wiped away one or two times daily, we highly recommend that you see your vet.
Finally, if the eyes are red and swollen, or if your cat is excessively rubbing the eyes, make an appointment with the vet. The vet would advise you regarding the best treatment for your pet. In some cases, you may need to administer a few eye drops on a regular schedule.
However, in other cases, the eye discharge may lead your vet to find another underlying condition that needs to be addressed.
Your cat's eyes are incredibly fragile and important. Trust your gut. If you think there may be something wrong, we highly recommend seeking a professional, veterinary medical opinion.
Diagnosing Discharge in Cat Eyes
At the vet, you should expect a series of tests. During the initial exam, it is important to provide as much information as possible, so that your vet can make an accurate diagnosis.
Your vet will likely perform a complete physical exam, check your cat's temperature, and may request a blood test to rule out certain diseases.
These tests will also help to determine if your cat is suffering from seasonal allergies, or if there is potentially an infection elsewhere in the body.
Additionally, your veterinarian will use a tool called an ophthalmoscope. If you've had an eye exam you'll recognize the tool, as it’s also used in humans.
The ophthalmoscope allows the vet to see a magnified image of the eye. If a diagnosis is still unclear or inconclusive, the vet will likely administer specific eye drops and perform a test called the fluorescein eye stain test.
The vet will once again examine the eye with an ophthalmoscope and check for any injury or ulcers.
Treating Cat Eye Discharge
The appropriate treatment of cat eye discharge will vary based on the underlying cause.
Before we get into specifics, we want to remind you to never reuse eye medication from a previous ailment, even if you believe your cat is having a recurrence.
You can inadvertently cause considerable injury or worsen the condition by using the wrong medication for your cat's current eye problem.
Treatment for Conjunctivitis in Cats
Treating conjunctivitis in cats will vary, based on the cause. It is always best to get the advice of your vet on the most effective treatment for your cat’s specific condition. Conjunctivitis caused by pollen, weeds, dust, and other environmental irritants may be alleviated by a steroid ointment. However, steroid ointments should be avoided if viral infections are detected or suspected, as they can make the condition worse.
Antibiotic ointments are generally prescribed for feline conjunctivitis caused by a bacterial infection.
Treating Feline Upper Respiratory Infection
Treatment of an upper respiratory infection will vary based on the severity of the infection, the cause, and the other signs that are present.
The vet would commonly prescribe specific eye medications, antibiotics, fluids, and decongestants to relieve the signs and treat the infection.
Treating Corneal Disorders
Treatment of a corneal disorder will often depend on the severity of the condition. Treatment will also vary based on the specific cause of the inflammation.
One of the most important ways to care for a corneal disorder is to ensure the eye is kept clean. Additional treatment options often include an antibiotic eye ointment or antibiotic eye drops, as well as eye drops that promote healing.
In some cases, removing loose corneal tissue, cauterization, or surgery is necessary to relieve the inflammation and prevent further damage.
Treatment for Watery, Tearing Eyes
If your cat has blocked tear ducts, a procedure performed under general anesthesia may be necessary.
The procedure will allow your vet to flush out the blockage. If an infection is present, the vet will likely prescribe antibiotic eye drops.
An appropriate treatment plan for uveitis can be difficult as it should be based on the underlying cause of the inflammation.
However, the culprit can be difficult to determine, and at times impossible to pinpoint. In order to relieve the pain and irritation, vets often recommend an eye ointment or drops.
Treating Cat Eye Infections
Bacterial infections and viral infections have the potential to cause a lot more damage that may not be limited to the eye.
For instance, secondary bacterial infections can lead to pneumonia or other severe ailments. It is imperative that any cat with an eye infection is examined, properly diagnosed, and treated by a veterinary professional.
Treatment may include antibiotics, medications to control the clinical or physical signs, and supportive care.
Dry Eye Treatment
While the focus of this article is primarily the overproduction of tears, it is also important to be aware that some conditions may cause dry eyes, which can be equally severe and may also produce a thick abnormal discharge.
Treating chronic dry eye often involves eye drops or ointments, antibiotics, artificial tears, and/or immune-suppressing drugs.
Again, a chronic lack of tear production can lead to blindness and should be taken very seriously. Therefore, seek veterinary medical attention for your pet.
Preventing Cat Eye Discharge
Thankfully, there are a few ways that you can prevent the development of eye disorders and therefore prevent an abnormal eye discharge. Again, the discharge is merely a sign, you'll want to focus on preventing the underlying cause.
First, do your best to avoid environments that are overcrowded with cats. Eye infections are transmitted extremely easily. The more cats around, the higher the risk.
Next, it is important to keep the area around the eyes clean. Don't allow the discharge to buildup. Cat owners can use a wet cotton ball to gently wipe away the excess fluid and keep their feline's eyes bright and clear.
Be sure to use a different, clean cotton swab for each eye, particularly, if for any reason you feel that there may be an infection.
Additionally, be sure to stay away from any over-the-counter washes or drops, unless your vet has specifically prescribed them.
Remember, never reuse drops or medications from a previous ailment. Administering the wrong medication to your cat's fragile eyes can have irreversible consequences.
Finally, stay alert. As we previously mentioned, it is so important to know your cat's "normal" behavior and physical state. Only then will you be able to pick up on when something is "off" early on.
When it comes to the eyes, the sooner you can figure out what's wrong, the better the chances that your cat will recover without any permanent damage.
Cat Eye Discharge: The Bottom Line
At the end of the day, we know that you want the very best for your beloved feline friend. Don’t be tempted to brush off unusual discharges from your cat’s eyes as ‘no big deal’.
We hope this article has convinced you that excessive discharge can be a telltale sign that something could be very wrong.
Again, trust your instincts. If something seems wrong with your fur baby, make an appointment with your veterinarian. Your cat's eyes are an extremely important part of their well being and something you, as a responsible pet parent, should not overlook.
Petal Smart is a veterinarian who, after a brief stint in clinical practice, has been a medical, veterinary, and science editor for the past four years. She has edited hundreds of research studies that have been published in various academic journals, and more recently, she has been editing blog articles on pet health. She holds a DVM (Hons) from the University of the West Indies - St. Augustine. Her pets in the past have included dogs, fish, birds, and a turtle. At times, she also likes to think of herself as a horse whisperer. You can connect with her on LinkedIn.
*This article has been edited and updated for publication by Petal Smart, DVM.