Cat Eye Problems: Third Eyelid – What You Need to Know
Cat eye problems involving the third eyelid are not uncommon, but they can be quite concerning for pet owners. As a responsible cat parent, it’s essential to understand the potential issues that can arise with your feline friend’s eyes. In this article, we will discuss the third eyelid in cats, what it is, when you should be worried, and how to treat it.
What is the Third Eyelid in Cats?
Cats, like many other animals, have a third eyelid. This additional eyelid, also known as the nictitating membrane or “haw,” is a thin, semi-transparent membrane located in the corner of the eye, nearest to the nose. It acts as an extra layer of protection for the eye, helping to keep it moist, remove debris, and shield it from injury.
When Should I Be Worried About My Cat’s Third Eyelid?
While the third eyelid is usually not visible in healthy cats, there are instances when it may become more prominent. Sometimes, a partially visible third eyelid is a normal response to various situations, such as when a cat is relaxed or sleepy.
However, if your cat’s third eyelid is consistently visible or suddenly appears, it could be a sign of an underlying issue. According to Hospital Veterinari Glories, there are several causes for the third eyelid to be more noticeable:
- Eye infections or inflammation (conjunctivitis)
- Foreign objects in the eye
- Corneal ulcers or injuries
- Neurological issues
- Upper respiratory infections
- General illness or weakness
- Haws syndrome
It’s essential to closely monitor your cat and consult your veterinarian if you notice any changes in their third eyelid.
Is Cat Third Eyelid Showing an Emergency?
While a visible third eyelid is not always an emergency, it could be indicative of a more serious issue. If your cat is displaying additional symptoms, such as eye discharge, redness, squinting, rubbing their eyes, or exhibiting signs of pain or discomfort, it’s essential to seek veterinary attention as soon as possible.
VCA Hospitals emphasizes that conjunctivitis, or inflammation of the conjunctiva (the tissue that lines the eyelids and covers the front part of the eye), is a common cause of the third eyelid’s prominence. Conjunctivitis can be triggered by allergies, infections, or foreign objects and requires prompt treatment to avoid complications.

How Do I Treat My Cat’s Third Eyelid?
Treatment for a visible third eyelid depends on the underlying cause. Once your veterinarian has determined the reason for the issue, they will prescribe the appropriate course of action. This may include:
- Antibiotics or antiviral medications for infections
- Anti-inflammatory medications to reduce inflammation
- Eye drops or ointments for irritation or dryness
- Pain relief medications if your cat is in pain
- Removal of foreign objects, if present
- Treatment for underlying systemic illnesses
It’s crucial to follow your veterinarian’s instructions and administer any prescribed medications as directed.
What is Haws Syndrome and How is it Treated?
Haws syndrome is a condition that causes the third eyelid to become more visible in both eyes, usually without any accompanying inflammation or discharge. The exact cause of Haws syndrome remains unknown, but it is often associated with gastrointestinal problems, such as inflammatory bowel disease or parasitic infections.
According to AnimalWised, treating Haws syndrome typically involves addressing the underlying gastrointestinal issue. Once the primary problem is resolved, the third eyelid should return to its normal, hidden position. Your veterinarian may prescribe medications to treat the gastrointestinal condition, as well as deworming medications if parasites are suspected. Additionally, they may recommend dietary changes or supplements to improve your cat’s overall gastrointestinal health.
What Can I Do to Prevent Cat Eye Problems Related to the Third Eyelid?
While it’s not always possible to prevent issues with the third eyelid, there are steps you can take to promote your cat’s overall eye health and reduce the risk of problems:
- Schedule regular veterinary check-ups to catch potential issues early
- Keep your cat’s living environment clean and free of dust or debris that could irritate the eyes
- Monitor your cat for signs of illness, such as sneezing, coughing, or changes in appetite
- Regularly groom your cat to remove loose hair and prevent it from getting into their eyes
- Avoid using harsh chemicals or fragrances around your cat, as these can cause irritation
- If your cat goes outdoors, ensure they are up-to-date on vaccinations and parasite preventatives

What Other Eye Problems Can Affect Cats?
In addition to issues with the third eyelid, cats can experience a variety of other eye problems.
Some of these issues include:
- Cataracts: A clouding of the lens within the eye that can lead to impaired vision or blindness if left untreated.
- Glaucoma: Increased pressure within the eye, which can be painful and cause irreversible damage to the optic nerve if not treated promptly.
- Uveitis: Inflammation of the uvea, the middle layer of the eye, which can cause redness, swelling, and pain. It may be a sign of an underlying systemic disease or infection.
- Retinal detachment: The separation of the retina from the back of the eye, which can result in sudden blindness. This condition is a medical emergency and requires immediate veterinary attention.
- Entropion: A condition in which the eyelid rolls inward, causing the eyelashes to rub against the eye and lead to irritation, corneal ulcers, and possible scarring.
- Dry eye (keratoconjunctivitis sicca): A lack of tear production, which can cause the eye to become dry, irritated, and more susceptible to infections.
If you notice any changes in your cat’s eyes or vision, it’s essential to consult with your veterinarian as soon as possible. Early detection and intervention can make a significant difference in the outcome and long-term health of your cat’s eyes.
The Importance of Monitoring Your Cat’s Eye Health
Maintaining your cat’s eye health is a crucial aspect of their overall well-being. Regularly monitoring your cat’s eyes for any changes, such as redness, discharge, or changes in the third eyelid’s visibility, can help you identify potential problems early on. By working closely with your veterinarian, you can ensure that your cat receives the appropriate care and treatment for any eye issues they may encounter.
In conclusion, cat eye problems involving the third eyelid can range from mild to severe, but understanding the signs and knowing when to seek veterinary help is key to ensuring your cat’s eye health. Whether it’s an infection, inflammation, or an issue like Haws syndrome, addressing the underlying cause is essential for proper treatment and recovery. By staying vigilant and providing your feline friend with regular care and attention, you can help to prevent eye problems and maintain their overall well-being.
Remember, your cat’s eyes are a vital part of their overall health and quality of life. By monitoring their eye health and seeking veterinary advice when needed, you can help ensure that your furry friend enjoys a happy, healthy life with clear vision. So, keep an eye on those beautiful feline eyes, and don’t hesitate to reach out to your veterinarian if you have any concerns. Your cat will thank you for it!
You also might be interested in:
Discussion about this post