Canine conjunctivitis: know the types and how to treat the pet

Whoever has a pet dog knows that it is necessary to always be aware (a) of possible health problems of the pet.

Like humans, pets are also exposed to agents that cause infections, such as bacteria and fungi that can trigger disease.

Among them is conjunctivitis , an inflammation in the eye region.


What is canine conjunctivitis?

Canine conjunctivitis is an inflammation that occurs in the eyes of dogs, more specifically in the mucosa that covers the eyelids and the white part of the eye, called conjunctiva.

This part of the body has the function of protecting the eyes and, when affected, can impair the animal’s vision, in addition to causing great discomfort.

In general, the problem can have several causes, such as dry eyes, caused by air pollution or irritation of the eyes due to the presence of foreign bodies, such as dirt.

It is worth mentioning that, although humans also have problems with conjunctivitis, they are different diseases and there is no possibility of transmitting the pet to the owner and vice versa.

Regardless of the origin, if it is not treated properly, conjunctivitis can even cause blindness in the pet and, therefore, it is important to be aware of the symptoms.

Types of canine conjunctivitis

Although it is usually characterized only as canine conjunctivitis, the disease has some subcategories, named according to the cause and form of the problem.

Among the main ones, there are:


Allergic conjunctivitis is caused by the body’s reaction to contact with substances or products that may be irritating to the pet.

In general, allergy can be caused by:

  • Pollen;
  • Mites;
  • Dirt in general;
  • Bug bite;
  • Cleaning products;
  • Contact with plants.

In response to allergy, the dog’s body can stimulate the development of conjunctivitis.

Bacterial and fungal

As the name implies, bacterial or fungal conjunctivitis is caused by bacteria or fungi.

It is usually manifested due to the proliferation of these organisms in the region of the eye, caused by contact with contaminated objects, or the very contact between dogs.


Viral conjunctivitis is the one that originates from the infection generated by some viruses. In general, it is the secondary manifestation of other viral diseases, such as distemper – a disease that affects the respiratory and ocular systems of dogs.

Thus, it is usually among the symptoms of other diseases.


Also called dry eye syndrome, keratoconjunctivitis is caused by inflammation of the tear glands and other parts of the eye structure.

When this occurs, it usually causes a deficiency in tear production, which can cause the animal to dry out the eyes.

With the dry eye condition, there is the possibility of manifestation of keratoconjunctivitis, that is, conjunctivitis caused by dryness of the eye structure.


Neonatal conjunctivitis is one that occurs in the first days of the animal’s life.

It can manifest both before and after the pet opens its eyelids for the first time and is usually associated with infection by bacteria or viruses.


Follicular conjunctivitis is one that occurs when there is inflammation of the inner cells of the eyes, called lymphoids.

In these cases, there is swelling and redness of the region, which can change the texture of the inside of the eyelid.

How is the dog infected?

There are different ways for the dog to contract conjunctivitis, from simple causes such as direct contact with dirt, to those originating from microorganisms, such as bacteria.

In animals, unlike conjunctivitis that occurs in humans, it is not common for contagion to be spread from one animal to another.

In general, the main causes and forms of infection of pets are:

Strange body

The contact of the pet with a foreign body to the eye, such as objects, dust and dirt, for example, can cause irritation of the eyeball.

The very action of keeping your head out of the car on a walk, for example, can be the cause of the manifestation of the problem of conjunctivitis in the pet.

This is because wind and air pollution can cause injuries and irritation in the region.

This condition can evolve and stimulate an inflammation or allergy in the eyes, resulting in the manifestation of conjunctivitis.


Microorganisms such as bacteria and fungi are also responsible for the appearance of the problem.

Their proliferation often occurs with direct contact with other dogs or even contaminated objects, such as beds or toys. Thus, infectious agents can affect the eyes and trigger conjunctivitis.

Eye dryness

Eye dryness is a condition that affects the lacrimal glands, the conjunctiva and the cornea of ​​the animal’s eye.

These structures are responsible for the production of tears, the lining of the eye and the passage of light in the vision.

When affected, the production of tears can be altered and there is the possibility of triggering ocular dryness, leaving the sensitive region, which can lead to inflammation such as conjunctivitis.


If the pet has suffered any trauma that affected the eye region, such as bumps or falls, it is possible that there has been an injury to the internal structures of the eye.

Bruises in the region, even if superficial, can cause inflammation and progress to conjunctivitis.

Immune reaction

Some dogs have a genetic predisposition to autoimmune diseases , that is, those in which the pet’s organism attacks its own cells.

In general, when they come into contact with external agents such as dust, for example, some problems can be triggered and, among them, is conjunctivitis.

Unlike allergic conjunctivitis, which can affect any pet, the autoimmune type is related to a pre-existing disease.

Secondary diseases

The presence of secondary diseases is one of the ways for the dog to contract the problem.

Pathologies such as Canine Distemper – a viral disease that causes respiratory and optical problems – and Hepatitis – a viral disease that attacks the liver of dogs – can be the source of the manifestation of conjunctivitis.

This is because some diseases that affect pets have among the possible symptoms and effects the onset of conjunctivitis.

Symptoms: how to know that the pet has conjunctivitis?

Like other diseases, conjunctivitis has some signs that indicate the onset of the problem.

In general, the main symptoms are:

  • Red eyes;
  • Swelling;
  • Eye discharge;
  • Excessive paddles;
  • Itch;
  • Difficulty keeping eyelids open;
  • Blink constantly;
  • Sensitivity to light.

Treatments: how to care for the pet?

The treatment of canine conjunctivitis is usually simple, consisting of the application of eye drops or antibiotics and the proper cleaning of the pet’s eyes, with saline, for example.

In general, the therapeutic resource varies according to the pet’s clinical condition and can only be indicated by a veterinarian.

Therefore, it is worth taking the animal to a consultation and always follow the guidelines of the professional.

What is the best eye drops for canine conjunctivitis?

Eye drops are used in the mildest cases of canine conjunctivitis, usually when the inflammation is not advanced.

In general, the product serves to lubricate, moisturize, reduce irritation and remove secretions from the eyes of the pet.

It should be applied directly to the eyes, usually 2 to 3 times a day. The frequency of use may vary according to the size of the dog and also the clinical picture.

There are different types of eye drops and only a trained professional can determine which one is best for your pet.

Some options for eye drops that can be indicated are:

  • Tobrasyn eye drops ;
  • Optivet Tears Veterinary Eye Drops ;
  • UCB eye drops for dogs and cats;
  • Ciprovet Labyes eye drops for dogs, cats and horses.

It is worth mentioning that the use should be made only under veterinary guidance, so that there is no worsening of the condition and undesirable effects.

What is the best antibiotic for canine conjunctivitis?

Antibiotics are generally used in the most severe cases of the problem, when the inflammation is already advanced.

They aim to decrease inflammation of the conjunctiva and are usually in the form of ointment.

Its administration should be done only under the guidance of a trained professional.

Among the options that can be recommended for treatment are:

  • Keravit .

Canine conjunctivitis and distemper

It is common to hear about the relationship between conjunctivitis and distemper. This, because despite being different diseases, distemper can cause conjunctivitis.

Thus, conjunctivitis manifests as a secondary sign of distemper.

In general, this disease is a serious condition caused by viruses of the paramixovirirdae family . It triggers some symptoms like:

  • Difficulty breathing;
  • I put in the respiratory canal;
  • Cough;
  • Nasal discharge;
  • Pneumonia;
  • Inflammation of the ocular structure;
  • Injury or alteration of the retina;
  • Dry keratoconjunctivitis – dry eye.

By causing changes in the ocular structure, distemper can stimulate the appearance of conjunctivitis.

How to identify canine conjunctivitis?

If your pet has any of the symptoms of conjunctivitis, such as difficulty opening the eyes or excessive tearing, it is essential to take him to the veterinary consultation, so that the correct diagnosis can be made.

In general, the professional will evaluate the pet and, if necessary, request the performance of some tests to identify more precisely the causes of the problem.

Some of the tests that can be done for confirmation are:

Schirmer tests

The Schirmer test, also known as the tear test, is one of the methods used for the diagnosis of conjunctivitis.

The technique consists of assessing whether the amount of tears produced by the animal is adequate or if there are any changes.

For this, the professional puts a strip of paper on the pet’s lower eyelids for 5 minutes.

After that time, the strips are removed and the level of production of the tears is measured, according to the part of the paper that has become damp.

Biomicroscopia ocular

Ocular biomicroscopy consists of examining the animal’s eye with the help of a biomicroscope, also known as a slit lamp.

This device allows analyzing both the anterior segment – cornea, iris, ciliary body, aqueous and crystalline humor – and posterior segment – vitreous, retina and choroidal humor – of the eyes.

Is there a way to prevent it?

-Yeah . In general, the prevention of canine conjunctivitis can be done with basic cleaning practices, both for the animal and the owner.

The main ways to avoid the problem are usually:

Maintain good hygiene habits

The care and hygiene of the eye area is an essential factor in the prevention of conjunctivitis.

It is important to keep the pet’s eyes always clean so that there is no proliferation of bacteria in the region, for example.

In addition, to further intensify hygiene and decrease the risk of infection, every time you touch the animal’s face, the guardian’s hands must be properly cleaned with soap and water.

Trim excess hair near the eyes

If the dog shows many around the eyes, it is worth trimming the wires in this region.

This is because the hair can retain dirt and bacteria that, if they come in contact with the eyes, can cause infections such as conjunctivitis.

Frequent visits to the vet

Carrying out visits at least once a year at the veterinarian or veterinarian is also relevant to keep the pet’s health up to date.

In this way, the professional will be able to assess possible risks of manifestation of conjunctivitis, in addition to assessing the pet’s health in general.

The idea of ​​having a pet can be encouraging, as several people look to fellow animals to share their lives.

However, not only through games and fun, the relationship between tutor (a) and pet is formed.

Just like human beings, animals can also get sick and need care from their owners.

This is the case of dogs that are affected by canine conjunctivitis and need treatment to improve their condition.

Despite being a very uncomfortable problem, with the necessary professional care and care, the pet tends to recover well.

Want to know more about problems that can affect your pet ? The Healthy Minute has other complete content for you! Read more and stay informed about your pet!