How to Treat Conjunctivitis in Dogs

French bulldog getting an eye exam on vet exam table
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Conjunctivitis is a condition of the eye that can affect dogs, cats, humans, and other animals. It may occur on its own or in conjunction with another eye condition. Like all eye problems, conjunctivitis should be treated by a veterinarian.

What is Conjunctivitis in Dogs?

The term conjunctivitis is used to describe inflammation of the conjunctiva, a thin layer of tissue that lines the eyelid and covers the sclera (white part) of the eye. The conjunctiva protects and helps lubricate the eye. When something causes the conjunctiva to become inflamed, the eye may appear red and swollen. Conjunctivitis is often called "pink eye." It can affect one or both eyes. In some cases, it may start in one eye and spread to the other.

Signs of Conjunctivitis in Dogs

  • Eye redness
  • Eye discharge
  • Swelling or puffiness of eyes
  • Squinting
  • Excessive blinking
  • Rubbing or pawing at the eyes

Causes of Conjunctivitis in Dogs

Conjunctivitis occurs when something causes the conjunctiva to become inflamed. Although it can occur on its own, it is sometimes a symptom of another eye disease. Potential causes of conjunctivitis in dogs include the following:

  • Allergies
  • Trauma to the eye
  • Infectious diseases, especially those that impact the upper respiratory system
  • Eye or eyelid masses
  • Tear production issues (such as KCS/dry eye)
  • Tear duct problems, such as obstruction
  • Cherry eye
  • Entropion or ectropion (eyelid abnormalities)
  • Distichiasis and other abnormal eyelash growth
  • Glaucoma
  • Anterior uveitis
  • Ulcerative keratitis

Conjunctivitis can cause dogs to paw at their eyes or rub their faces on things to relieve itching or pain. In doing this, the dog may make the eyes worse, even causing complications like corneal ulcers. Contact your vet right away if you notice this.

Conjunctivitis sometimes resolves on its own within a day or two, especially when it has been caused by allergies or a minor injury. It's important to contact your veterinarian right away if you notice signs of conjunctivitis that seem moderate to severe, or if you are worried about your dog. If mild signs persist for more than one to two days, a vet visit is necessary. Minor eye problems can quickly turn serious, so it's best to contact your vet sooner than later.

Treatment of Conjunctivitis in Dogs

The treatment for conjunctivitis generally depends on the cause. Your veterinarian will perform a thorough eye exam and physical exam to look for underlying diseases and other problems in the body. Your vet may need to perform special eye tests to make a diagnosis. This may include a test to measure tear production, a stain to look for corneal ulcers or lesions, and the measurement of intraocular pressure.

If the dog's conjunctivitis appears to be related to an eye disease or other issue in the body, the vet will recommend treating that condition along with conjunctivitis. Treatment may involve the use of eye drops or ointments along with oral medications. Some eye conditions will need to be treated surgically. In addition, your vet may refer you to an ophthalmologist when specialized treatments or diagnostics are necessary.

Primary conjunctivitis (no underlying cause) is often treated with eye drops or ointment that contains steroids to reduce inflammation. Antibiotic eye medications may also be used to treat or prevent a possible bacterial infection in the eye. Eye medications usually need to be applied two to four times a day.

It's important to follow your vet's recommendations when it comes to treatment. Try not to skip treatments when they are due. Contact your vet immediately if the eye is not improving or if it is getting worse.

How to Prevent Conjunctivitis in Dogs

You may not be able to prevent your dog from getting conjunctivitis, but you may be able to catch it early and visit the vet before it becomes severe. Remember to contact your vet if your dog develops an eye abnormality.

If your dog is prone to environmental allergies, ask your vet about using an antihistamine like diphenhydramine to minimize the allergic response.

If you know your dog has an existing eye condition, it's important to keep it under control. Give all medications as directed and contact your vet if there is a change to the eyes.