What is Feline Conjunctivitis?
Feline conjunctivitis is inflammation of the conjunctiva, the thin transparent tissue that lines the inner eyelid and covers the front of the eyeball, in cats (VCA Hospitals). It is characterized by swelling, redness, and discharge from the eye(s).
Common causes of conjunctivitis in cats include viral infections like feline herpesvirus and calicivirus, bacterial infections from chlamydia and mycoplasma, and irritants like dust, debris or chemicals (Cornell Feline Health Center).
Symptoms of conjunctivitis in cats include redness of the white of the eye, swelling and itching of the conjunctiva, increased blinking and eye discharge that can be clear, yellow or greenish. Affected cats may keep their eyes closed or partially closed due to discomfort (PetMD).
Why It’s Important to Treat
Conjunctivitis can cause considerable discomfort and pain for cats. The inflammation and irritation makes their eyes feel scratchy and dry. Vision can also become impaired as discharge accumulates and the eyes water. Some cats will avoid bright lights due to increased sensitivity. If conjunctivitis goes untreated, it can lead to other problems like corneal ulcers or scarring. Severe cases that are left unchecked may progress to corneal sequestra or corneal perforation, both of which can cause permanent blindness. That’s why it’s critical to have your vet properly diagnose and treat your cat’s conjunctivitis before it leads to lasting damage.
Diagnosing the Cause
Determining why your cat’s conjunctivitis won’t go away starts with a thorough examination by your veterinarian. The vet will perform a complete eye exam to check for signs of infection, inflammation, or irritation. They may perform additional tests to identify the specific cause of the conjunctivitis.
If the conjunctivitis is suspected to be viral, the vet may take a swab of the eye discharge and have it tested for common feline viruses like herpesvirus and calicivirus. These viruses often cause upper respiratory infections in cats as well (https://vcahospitals.com/know-your-pet/conjunctivitis-in-cats).
For bacterial conjunctivitis, cultures can be taken to identify the type of bacteria involved. Common bacteria include Staphylococcus, Streptococcus, and Chlamydia species. Knowing the causative bacteria allows for proper antibiotic treatment.
If an irritant is suspected, the vet will perform a thorough eye exam to look for foreign material, eyelid issues, or other sources of irritation. They may flush the eye to remove debris. Removing the source of irritation is key.
In some cases, additional tests like bloodwork or imaging may be needed to diagnose underlying diseases contributing to recurring conjunctivitis.
Treating Viral Conjunctivitis
Viral conjunctivitis such as feline herpesvirus is very contagious between cats. Unfortunately, there is no cure for the underlying viral infection, only treatments to help manage the symptoms. Viral conjunctivitis will usually resolve on its own within 2-3 weeks as the cat’s immune system fights off the virus. However, symptomatic treatment can help provide relief and prevent secondary infections during this recovery period.
Symptomatic treatment involves using topical ophthalmic ointments, eye drops, and oral antiviral medications. Topical antibiotics like oxytetracycline, tobramycin, or fusidic acid can help prevent secondary bacterial infections (VCA Animal Hospitals). Cleaning the eyes regularly with saline solution can also help remove discharge and soothe inflammation. Oral antiviral medications like famciclovir may be prescribed in severe cases to suppress viral replication and reduce symptoms. Your veterinarian can recommend the most suitable medications and treatment plan based on your cat’s specific condition.
While viral conjunctivitis often resolves on its own, it’s important to follow your vet’s treatment plan to help manage symptoms and prevent complications. Be vigilant for any worsening of symptoms and follow up promptly with your vet if the condition persists beyond 2-3 weeks.
Treating Bacterial Conjunctivitis
Bacterial conjunctivitis is commonly treated with antibiotic eye drops or ointments to kill the underlying bacteria causing the infection. Some commonly prescribed antibiotics for cats include tetracyclines like doxycycline, aminoglycosides like gentamicin, and fluoroquinolones like ciprofloxacin (source).
It’s important to administer the antibiotic drops or ointment as prescribed by your veterinarian and complete the full course, even if symptoms improve. This helps ensure the infection is fully eliminated. Be sure to gently wipe away any eye discharge before applying the medication.
In some cases, oral antibiotics may be prescribed in addition to topical treatment for severe or chronic bacterial conjunctivitis. Oral doxycycline is commonly used. Underlying issues like eyelid abnormalities, eye injuries, or immune deficiencies may also need to be addressed as part of the treatment plan (source).
If symptoms do not resolve within 1-2 weeks with appropriate antibiotic treatment, it’s important to follow up with your veterinarian to re-evaluate your cat. There may be an underlying complicating factor or resistant infection requiring further care.
Treating Irritant Conjunctivitis
The first step in treating irritant conjunctivitis is identifying and removing the irritant causing the inflammation. Common irritants include dust, wind, smoke, cleaning products, shampoo, and other foreign materials that may get in the eye. Keeping the eye clean by flushing it with an eyewash or sterile saline can help remove irritants.
Medications can provide symptomatic relief from irritant conjunctivitis. Over-the-counter eye lubricants containing artificial tear solutions may help soothe eyes and wash away irritants. Antihistamine eye drops like ketotifen fumarate can relieve itching and reduce inflammation. Topical antibiotic ointments may be prescribed if a secondary bacterial infection develops (https://vcahospitals.com/know-your-pet/conjunctivitis-in-cats). Steroid eye drops are sometimes used for short-term relief of severe inflammation but should only be used under veterinary supervision.
Keep the cat indoors during treatment to prevent re-exposure. Promptly treating the irritant and providing relief allows most cases of irritant conjunctivitis to resolve within a few days.
Ensure Proper Administration
Proper administration of eye medications is critical for your cat’s recovery. When applying drops or ointments, follow these techniques:
– Have an assistant hold and comfort the cat in their lap while you administer the medication. This avoids having to scruff or restrain the cat, reducing stress.
– Tilt the cat’s head up and gently pull down the lower eyelid to form a pocket. Drop the medication into this pocket, being careful not to touch the eye.
– After applying drops, gently hold the eyelid closed and apply light pressure against the corner of the eye. This helps the medication absorb into the eye rather than drain out.
– When applying ointment, squeeze out a ribbon onto the surface of the eye. Allow your cat to blink to distribute the medication across the eye.
It’s critical to complete the full course of treatment, even if your cat’s eyes look better. Stopping medication early can allow the infection to recur. Follow your veterinarian’s instructions precisely and finish all prescribed medications. Consistent proper administration ensures the best chance of full recovery.
For more tips, see Applying Eye Drops to Cats and Applying Eye Ointments to Cats.
When It Doesn’t Resolve
In most cases, feline conjunctivitis resolves within 1-2 weeks when properly treated. However, sometimes conjunctivitis can persist beyond normal timeframes or keep recurring. There are a few potential reasons this may happen:
Feline herpesvirus is the most common cause of chronic or recurring conjunctivitis in cats. The herpesvirus never truly goes away and remains dormant in the body. Stress or other illnesses can trigger the virus to reactivate, causing another bout of conjunctivitis. Recurrences are especially common in shelters, boarding facilities, or multi-cat households where exposure risk is higher. Cats with weakened immune systems may also be prone to more frequent recurrences [1].
Inadequate treatment or premature discontinuation of medication can also lead to persistent or recurring conjunctivitis. It is important to follow the full course of prescribed eye drops/ointments as directed by your veterinarian, even if symptoms seem to resolve. Stopping treatment too soon gives bacteria or viruses a chance to take hold again before being fully eliminated.
Using the wrong type of medication is another potential factor if conjunctivitis keeps recurring. Viral, bacterial, and irritant conjunctivitis require different treatments. If the underlying cause is not accurately diagnosed and treated, symptoms will likely continue. Bacterial resistance to certain antibiotics may also play a role.
Sometimes debris or foreign material gets trapped under the third eyelid or eyelids. This can cause ongoing irritation and infection. Your vet may need to perform a thorough eye flush to remove the debris if it cannot be easily seen.
In rare cases, an underlying eye condition like dry eye, eyelid/eyelash abnormalities, or corneal ulcers may be the real culprit behind chronic conjunctivitis. Your vet can perform various eye tests to check for these issues if conjunctivitis persists despite treatment.
Complications
If left untreated, conjunctivitis can lead to some serious complications in cats including:
Corneal damage: The cornea is the clear outer layer of the eye. In chronic conjunctivitis, the inflammation and discharge can cause ulcers and scarring on the cornea 1. These lesions are painful and can permanently damage vision.
Vision loss: If corneal scarring is severe or left untreated, it can lead to partial or complete vision loss. The drainage and swelling from conjunctivitis can also obstruct vision until the infection clears 2. That’s why it’s critical to get prompt veterinary treatment.
Preventing complications involves identifying and properly treating conjunctivitis early on. Catching it quickly and using the right medications can help avoid long-term eye damage in cats.
Prevention
The best way to prevent conjunctivitis in cats is to reduce their exposure to potential infections and irritants. Keep their environment clean by regularly washing bedding and disinfecting surfaces. Avoid exposure to stray cats that may carry contagious illnesses. Limit time spent outdoors in dusty or pollen-filled environments that could irritate their eyes.
Routine veterinary checkups are also important for prevention. Your vet can examine your cat’s eyes closely, provide vaccines that reduce the risk of viral infections, and recommend preventative medications if your cat has chronic conjunctivitis issues. Keeping your cat’s general health optimized with good nutrition, exercise, and minimal stress will also help their immune system fight off conjunctivitis.