Conjunctivitis in Dogs: A Comprehensive Guide for Pet Owners

Conjunctivitis, often referred to as “pink eye,” is an eye condition that affects dogs. It occurs when the conjunctiva, the thin membrane that lines the inner surface of the eyelids and covers the white part of the eye, becomes inflamed. Our MedVet ophthalmology experts want you to know what signs to look for with conjunctivitis, when to see a veterinarian, how it’s treated, and ways to help prevent your dog from getting the condition.

What is Conjunctivitis in Dogs?

The conjunctiva is a mucous membrane that covers the white of the eye and lines the inner eyelids. In dogs, this includes their third eyelid, known as the nictitating membrane, which offers additional protection. A dog’s third eyelid is in the corner of their eye, closest to their nose. You may see your dog’s third eyelid when they’re sleeping or waking, but it’s generally not visible in healthy eyes.

Conjunctivitis is the inflammation of the conjunctiva and can be caused by various factors. It may affect one or both eyes and can range from mild to severe. While not usually serious, conjunctivitis can cause discomfort in your dog and may necessitate veterinary care.

Causes of Conjunctivitis in Dogs

Several factors can lead to conjunctivitis in dogs, including:

1. Infections: Conjunctivitis can be caused by bacterial, viral, or fungal infections. In dogs, bacterial infections are a more common trigger, while in cats, conjunctivitis is often the result of viral infections, such as feline herpesvirus (FHV-1) and feline calicivirus (FCV).
2. Allergies: Environmental allergens, such as pollen, dust, mold, smoke, or exposure to certain indoor plants, can trigger an allergic reaction in the eyes.
3. Foreign Bodies: Small particles, like dust or debris, can get lodged in the eye and cause irritation.
4. Trauma: Injuries to the eye, such as scratches or punctures, can lead to inflammation.
5. Dry Eye: A condition known as keratoconjunctivitis sicca (KCS) can cause the eyes to become dry and inflamed.
6. Immune Disorders: In some cases, the immune system may attack the conjunctiva, leading to inflammation.
7. Tumors: Benign (non-cancerous) or malignant (cancerous) tumors can develop in the tissues surrounding the eye, including the conjunctiva.

Signs of Conjunctivitis in Dogs

Recognizing the signs of conjunctivitis is important for early intervention. Some common signs include:

• Redness or swelling of the conjunctiva
• Excessive tearing or discharge from the eyes (which can be clear, yellow, or green)
• Squinting or blinking excessively
• Pawing at the eyes
• Sensitivity to light
• Crusty or matted fur around the eyes

Conjunctivitis in cats is often highly contagious, particularly when caused by viruses. In dogs, however, it is less commonly contagious, except in cases involving specific bacterial infections or puppy conjunctivitis.

When to Seek Veterinary Care for Conjunctivitis

If you observe any of the signs mentioned in your dog, it’s important to consult your family veterinarian, especially if your dog has a history of eye problems or is prone to infections. While some cases of conjunctivitis might clear up on their own, others need medical treatment. If your dog has persistent conjunctivitis or potential corneal damage, your family veterinarian may refer you to a veterinary ophthalmologist. These specialists have advanced training in diagnosing and treating eye conditions.

Diagnosing and Treating Conjunctivitis in Dogs

Your veterinarian will perform a thorough examination of your dog’s eyes to diagnose conjunctivitis. This may include:

• Physical exam: Checking for redness, swelling, and discharge.
• Fluorescein stain: Applying a special dye to the eye to check for scratches or ulcers.
• Schirmer Tear Test: Measuring tear production to rule out dry eye.
• Culture and sensitivity testing: Taking a sample of the discharge to identify any bacterial or fungal infections.
• Cytology: Taking a sample of the discharge or the conjunctiva to identify abnormal cells.

Treatment for Conjunctivitis in Dogs

The treatment for conjunctivitis in dogs depends on the underlying cause. Common treatments include:

1. Eye drops or ointments: Eye drops or ointments may be prescribed to reduce inflammation, fight a viral or bacterial infection, flush out irritants, or lubricate the eye. You can administer eye drops or apply eye ointment to your pet at home.
2. Oral medications: Antibiotics or anti-inflammatory drugs may be given orally if the condition is severe or if there is a systemic infection.
3. Allergy management: If allergies are the cause, your veterinarian may recommend antihistamines or other allergy medications. They may also refer you to a veterinary dermatologist who’s spent years training specifically in the diagnosis and treatment of all diseases of the skin and coat.
4. Foreign body removal: If a foreign body is present, your veterinarian will remove it to alleviate the irritation.
5. Supportive care: Keeping the eye clean and free of discharge can help speed recovery. Your veterinarian may recommend using a warm compress to gently clean the eye.

The prognosis for conjunctivitis in dogs is generally good, especially with prompt and appropriate treatment. Most cases resolve within a few days to a couple of weeks. However, recurrent or chronic conjunctivitis may require ongoing management and regular veterinary check-ups.

Preventing Conjunctivitis in Dogs

While not all cases of conjunctivitis can be prevented, there are steps you can take to reduce the risk for your pet:

• Keep your dog’s environment clean: Regularly clean your dog’s bedding, toys, and feeding areas to minimize exposure to allergens and bacteria.
• Avoid exposure to irritants: Keep your dog away from smoke, chemicals, and other irritants that can cause eye irritation.
• Keep face fur trimmed: Especially in breeds with longer hair, keeping the fur around the eyes trimmed can prevent irritation.
• Clean eyes gently: Use a soft, damp cloth and baby shampoo to wipe away any dirt or discharge around the eyes.
• Regular veterinary check-ups: Regular health checks, including eye exams, can help detect and treat underlying conditions that may contribute to conjunctivitis.

Conjunctivitis in dogs is a common but treatable condition. By recognizing the signs, seeking veterinary care, and following the prescribed treatment plan, you can help your dog recover quickly and comfortably. If you have any concerns about your dog’s eye health, don’t hesitate to consult your veterinarian. They can provide personalized care tailored to your dog’s specific needs.

Learn more about veterinary ophthalmology.