Common Eye Infections and Conditions

1. Conjunctivitis (Pink Eye)

Description: Inflammation of the conjunctiva, the most common feline eye problem.

Causes:

• Viral: Feline herpesvirus (FHV-1) is the primary culprit.
• Bacterial: Often secondary to viruses or primary infections like Chlamydia felis.
• Allergies: To pollen, dust, or food.
• Irritants: Such as smoke, chemicals, or foreign bodies.

Symptoms:

Treatment:

• Bacterial: Prescription antibiotic ointments or drops.
• Viral: Antiviral medications and supportive care.
• Allergic: Antihistamines or identifying/removing the allergen.
• General: Warm compresses to clean away discharge.

2. Corneal Ulcers

Description: A scratch or erosion on the clear corneal surface.

Causes: Trauma (cat fights, scratches), foreign bodies, dry eye (KCS), or viral infections.

Symptoms:

• Intense squinting and pain.
• Excessive tearing (epiphora).
• A visible cloudy or opaque spot on the cornea.
• Obvious discomfort; cat may hide or avoid light.

Treatment:

• Aggressive antibiotic drops to prevent infection.
• Pain management (oral or topical).
• E-collar (cone) is essential to prevent self-trauma.
• Severe or deep ulcers may require surgical intervention.

⚠️ Emergency: A deep ulcer or descemetocele (where the deepest layer bulges) is a critical emergency requiring immediate care to prevent rupture.

3. Feline Herpesvirus (FHV-1)

Description: A widespread, lifelong viral infection that is a leading cause of ocular disease.

Key Facts:

• Over 80% of cats are exposed in their lifetime.
• The virus becomes latent and can reactivate during periods of stress or illness.
• It is highly contagious among cats.

Ocular Symptoms:

• Recurrent conjunctivitis.
• Corneal ulcers and keratitis (corneal inflammation).
• Chronic watery eyes.
• In severe cases, symblepharon (where the conjunctiva sticks to itself or the cornea).

Treatment & Management:

• Antiviral Drugs: Oral Famciclovir is commonly prescribed.
• Supportive Care: Keeping eyes clean, nutritional support.
• Stress Reduction: A stable environment is key to preventing flare-ups.
• L-lysine: Use is now debated; consult your vet as it may not be effective for all cats.

4. Chlamydial Conjunctivitis

Description: A bacterial infection caused by Chlamydia felis.

Characteristics:

• Highly contagious, especially in multi-cat households and shelters.
• Often starts severely in one eye before spreading to the other.
• Most common in kittens and young cats.

Symptoms:

• Severe, swollen conjunctivitis.
• Thick, yellow-green eye discharge.
• Mild respiratory signs (sneezing) may also be present.

Treatment:

• Oral Antibiotics: A 3-4 week course of Doxycycline is typical.
• Topical antibiotic ointment may also be used.
• Treat all cats in contact to prevent reinfection.

5. Uveitis

Description: A painful inflammation of the eye's middle layer (uvea).

Causes: Can be a sign of serious systemic disease:

• Infections (FIV, FeLV, FIP, toxoplasmosis).
• Trauma.
• Autoimmune disease.
• Cancer (especially lymphoma).
• Often idiopathic (no identifiable cause).

Symptoms:

• A deep, "ciliary flush" redness around the cornea.
• Cloudiness inside the eye.
• Constricted, small pupil.
• Severe squinting and pain.
• Possible blood in the anterior chamber (hyphema).

Seriousness: A true emergency. Can lead to glaucoma, cataracts, retinal detachment, and blindness.

Treatment:

• Intensive anti-inflammatory eye drops (steroids).
• Dilating drops to relieve pain and prevent adhesions.
• Crucially, diagnostic testing to find and treat the underlying cause.

6. Eyelid Abnormalities

• Entropion: Eyelid rolls inward, causing eyelashes to rub the cornea. Leads to ulcers and pain. Requires surgical correction.
• Ectropion: Eyelid rolls outward, exposing the conjunctiva to irritation and drying. May require surgery if severe.

Recognizing Eye Emergencies

Seek Immediate Veterinary Care For:

The Veterinary Diagnosis Process

Standard Ophthalmic Exam:

1. Visual Inspection: Assessment of eyelids, conjunctiva, and cornea.
2. Schirmer Tear Test: Measures tear production to rule out "dry eye."
3. Fluorescein Stain: A dye that glows under blue light, revealing corneal ulcers or scratches.
4. Tonometry: Measures intraocular pressure to diagnose glaucoma (high pressure) or uveitis (low pressure).
5. Ophthalmoscopic Exam: Views the internal structures (retina, optic nerve).

Additional Diagnostic Tests:

• Conjunctival Swab/Culture: Identifies specific bacteria.
• PCR Testing: Detects viral DNA (e.g., for herpesvirus).
• Blood Work & Urinalysis: To uncover underlying systemic diseases.
• Imaging: X-rays or ultrasound if a tumor or foreign body is suspected.

Home Care and Administering Medication

Step-by-Step Guide to Eye Drops/Ointment:

1. Wash your hands thoroughly.
2. Gently clean any crust or discharge from around the eye with a warm, damp cloth.
3. Steady your cat's head with one hand, using your thumb to gently pull down the lower eyelid.
4. For Drops: Hold the bottle 1-2 inches above the eye and apply the prescribed number of drops into the pocket created by the lower lid.
5. For Ointment: Apply a thin ribbon along the inside of the lower eyelid.
6. Release your cat and allow them to blink, distributing the medication.
7. Reward with a treat or praise to create a positive association.

Pro Tips:

• Never let the applicator tip touch the eye, as this can contaminate the medication.
• Wait 5-10 minutes between administering different eye medications.
• Use an E-collar (cone) without exception if your cat is pawing at the eye.
• Complete the entire course of medication, even if symptoms seem to improve.

Supportive Home Care:

• Apply warm compresses to soften and remove crusty discharge.
• Ensure a quiet, stress-free recovery space.
• Maintain excellent nutrition to support immune function.

Prevention Strategies

1. Vaccination:

• The FVRCP core vaccine helps protect against Feline Viral Rhinotracheitis (herpesvirus) and Calicivirus, reducing the severity of respiratory and ocular symptoms.
• Note: Vaccination does not prevent infection but is crucial for disease management.

2. Environmental Management:

• Minimize Stress: Use pheromone diffusers (Feliway), provide hiding spots, and maintain routines to prevent herpesvirus flare-ups.
• Hygiene: Regularly clean food/water bowls, bedding, and litter boxes.
• Isolate Sick Cats: In multi-cat homes, isolate any cat showing signs of contagious illness.

3. Proactive Health Care:

• Annual Vet Exams: Include an eye check. Senior cats (7+) benefit from bi-annual exams.
• Monitor Daily: Be observant during regular interactions and grooming.
• Address Underlying Conditions: Manage chronic illnesses like diabetes or hypertension that can affect eye health.

Breed Predispositions

• Brachycephalic Breeds (Persian, Himalayan, Exotic Shorthair): Prone to tear staining, corneal exposure due to shallow eye sockets, and entropion.
• Breeds with Hereditary Conditions:
  • Abyssinians & Bengals: Progressive Retinal Atrophy (PRA).
  • Siamese: Strabismus (crossed eyes) and nystagmus.

Cost of Treatment (2026 Estimates)

Basic Eye Infection (e.g., simple conjunctivitis):

Complex or Severe Case (e.g., deep ulcer, uveitis):

Note: Costs vary significantly by geographic location and clinic. Pet insurance is highly recommended for managing unexpected veterinary expenses.

Prognosis and Outcomes

• Generally Good: Simple conjunctivitis, superficial corneal ulcers, and chlamydia (with proper treatment) typically resolve fully.
• Guarded/Chronic Management: Feline herpesvirus (lifelong, recurrent flare-ups), uveitis (depends on treatability of underlying cause).
• Serious/Poor: Untreated glaucoma, severe trauma, intraocular cancer, or infections that have caused irreversible structural damage.

Frequently Asked Questions (FAQs)

Q: Can I use human eye drops (like Visine) on my cat? A: Absolutely not. Many human medications contain ingredients (like steroids or decongestants) that can be extremely toxic to cats and worsen the condition. Use only veterinarian-prescribed medications.

Q: Will my cat's eye infection heal on its own? A: It is very unlikely and risky to wait. What appears minor can deteriorate quickly. Delaying professional care can lead to permanent scarring, vision loss, or the need for more invasive and expensive treatment.

Q: Is eye discharge always a sign of infection? A: No. While often due to infection, discharge can also signal allergies, a blocked tear duct, dry eye, or anatomical problems like entropion. A vet can determine the exact cause.

Q: Can I catch an eye infection from my cat? A: The risk is very low for most feline infections. Chlamydia felis has zoonotic potential but is rare. Always practice good hygiene, like washing hands after treating your cat's eyes.

Q: Why does my cat's eye problem keep coming back? A: The most common reason is Feline Herpesvirus (FHV-1). After the initial infection, the virus remains dormant in the nerves and can reactivate during times of stress, causing recurrent symptoms. Lifelong management is key.

Disclaimer: This guide is for informational purposes only and is not a substitute for professional veterinary advice, diagnosis, or treatment. Eye conditions can deteriorate rapidly. Always seek the advice of your veterinarian with any questions regarding your pet's health.