What is Conjunctivitis in Dogs: Types, Causes & Treatment

Conjunctivitis, or pink eye, is a phenomenon that causes itchy and uncomfortable eye conditions. Just like humans, conjunctivitis in dogs is quite common. So, knowing the signs and symptoms can help you identify the disease before causing lasting effects if you are a dog owner.

To learn more, keep reading!

Dogs have a third eyelid, or nictitating eyelid, in the inner corner of each eye. This is made of the conjunctiva, a soft tissue that protects the eyeballs and eyelids. If there is any inflammation or swelling in this tissue, it causes conjunctivitis.

Healthy conjunctiva is usually pink, but an infected one turns darker pink or red. Generally, it occurs in one eye, but if it is infectious, it may also spread to the other eye.

There are three types of conjunctivitis common among dogs:

1. Allergic Conjunctivitis: Dogs of any breed are susceptible to this kind of infection, but it more commonly harms those vulnerable to atopic dermatitis or hypersensitivity to common substances in the environment. Allergic conjunctivitis is common among young adults, but it can affect canines at any age.
2. Viral Conjunctivitis: Dogs encountering viruses that cause swelling of the membranes suffer from viral conjunctivitis. This is quite common and contagious. It can take three to four weeks to recover. Canine distemper virus and canine herpes virus are two such viruses that trigger the signs of viral conjunctivitis.
3. Bacterial Conjunctivitis: If a comparison is drawn between primary and bacterial conjunctivitis, the former is rather uncommon than the latter. On the other hand, secondary bacterial conjunctivitis in dogs is common because of its underlying medical issues. For instance, dry eyes, corneal ulceration, any abnormalities in the eyelids, etc.

Conjunctivitis in canines can result due to multiple causes. The list below highlights medical conditions that can make a dog more prone to pink eyes.

• Exposure to environmental allergens
• Viral infections
• Bacterial infections
• Compromised immunity
• Tumours in the eyelids
• Dry eye
• Entropion (rolling in of the lower eyelid)
• ectropion (rolling out of the lower eyelid)
• Abnormal growth of lashes
• Blockage in the tear ducts
• Any trauma from foreign objects or pollution
• High pressure in the eye
• Lower pressure in the eye
• Conditions associated with specific breeds, like nodular episcleritis in Collies
• Parasites are rather uncommon but a probable cause of conjunctivitis.

The primary sign that indicates pink eyes in dogs is their red eyes. If you suspect this condition, you can look for the other symptoms of conjunctivitis in dogs.

• Continuous blinking
• Watery eyes
• Clear, white, yellow, or green discharge from their eyes
• Swollen eyelids
• Eyelids sticking together
• Increased tendency to rub eyes with their paws or against any surface

Even though all dog breeds can develop this condition, there are certain breeds that are more prone to conjunctivitis. For instance:

• Retrievers
• Pekingese
• Hounds
• Poodle
• Pug
• Cocker Spaniel

Veterinarians conduct a thorough physical examination and check their eyes to find any underlying medical conditions.

The ophthalmic examination of dogs will consist of the following:

• First, a complete eye examination, including the eyelids, eye structure, the fur around the eyes, eyelashes, tear ducts and third eye.
• Tear production testing, also known as Schirmer tear testing, checks the amount of tear each eye produces.
• Corneal stain testing or Fluorescein stain testing is another non-invasive test that checks the cornea. In the process, a yellow stain is put on their eyes and under a special light, they are checked for any cuts, scrapes or other damages.
• Intraocular pressure testing to check the pressure in both eyes.

Apart from these tests, vets may order other additional tests. For instance:

• Bacterial culture
• Conjunctivae scraping or biopsy
• Allergy testing
• Viral testing
• Ultrasound of the eyeball
• Tear duct flushing

There are multiple causes of conjunctivitis in canines; hence there are various treatment approaches. Furthermore, the conjunctivitis treatment for dogs depends on its severity.

• Allergic Conjunctivitis: Most commonly treated with eye drops or ointments and sometimes oral steroids and antihistamines.
• Bacterial Conjunctivitis: In the case of these infections, topical antibiotics are recommended along with anti-inflammatory drugs.
• Viral Conjunctivitis: To boost immunity in cases of viral conjunctivitis, vets suggest oral antioxidants and, depending on their severity, other oral or topical anti-viral medications.
• Other Abnormalities: Dogs with eyelid or eyelash abnormalities may need surgeries to treat their chronic eye conditions.
• Immune-Mediated Medical Issues: Dogs with such conditions will need immunomodulatory medications that can be either topical or oral.

Medications

Some common medicines that treat conjunctivitis and its related symptoms in dogs are as follows:

• Topical gentamicin
• Tobramycin
• Oxytetracycline
• Ciprofloxacin
• Triple-antibiotic ophthalmic ointments/drops
• Prednisolone
• Dexamethasone
• Cyclosporine
• Tacrolimus

Home Remedies

If you notice early signs of conjunctivitis in your dog, like clear discharge or watery eyes. You may try these home remedies, but they do not treat the actual medical issue.

• Using sterile saline eye wash solutions to wash their eyes to clean the discharge carefully.
• Trying out holistic products to apply around the eyes or give them orally to clear out the tear ducts.
• Cold compresses are a common way many use to relieve their pain and itchiness.

Conjunctivitis treatment for dogs comes with some post-treatment recovery. For example, you should keep your dog away from other infected dogs and keep them free from eye trauma.

The dogs often try to rub their eyes as the condition leads to severe itchiness in and around their eyes. Even while they are under treatment for conjunctivitis, they can keep trying to scratch or rub their eyes. Hence, putting them in a pet cone is the best way to prevent them from scratching.

In addition, you must follow up with your veterinarian to check how your dog is reacting to the treatment methods. This also allows you to be up-to-date with their prognosis and if they need any change in their treatment.