Eye: Pink Eye


Dog pink eye is caused by two main factors, i.e. environmental factors and infectious agents. Environmental factors include foreign objects, dust, pollens, allergens, dust and other pollutants that can initially irritate the conjunctiva. This is followed by inflammation and secondary infections which is caused by opportunistic bacteria and fungus. This in turn ultimately worsens the condition.

On the other hand, bacteria, viruses and fungi can cause dog pink eye as a primary condition (starts in the eye vs. being related to another dog eye problem>. These microbes are transmitted through the air and contact the eye, causing bilateral inflammation of conjunctiva in dog eyes. These infections not only cause conjuntiva inflammation, but can also lead to the initiation of other opthalmic problems as well.


Clinically, conjunctiva of a dog eye appears “meaty” i.e. pink to reddish in color and swelled. Moreover, severe ocular (eye) discharge, irritation, redness, swelling, follicular hyperplasia (lymph node enlargement) and redness due to hyperemia (excess blood) is noted as the major signs. The examination of symptoms alone usually does not indicate the exact cause of the canine pink eye condition. One has to thoroughly examine the symptoms such as, e.g. bacterial and fungal infections which cause yellowish and viscous ocular discharge. This can cause the eyes to temporarily shut due to sticky discharge.

Similarly, allergens cause more irritation in the eye as compared to bacterial or fungal infections. Some foreign particles and pollutants may cause conjunctivitis. Such dog eye infections are observed unilaterally (in only one eye, while conjunctivitis caused by infectious agents is more commonly bilateral (in both eyes).

Another feature of canine conjunctivitis is dog eye irritation and pain. Allergens and foreign pollutants cause more eye irritation as compared to infectious agents. In either case, the patient might rub their face against hard objects, which can cause scratches and thus the dog can end up with problems that result from self injury such as the spreading of infections to the other eye or parts of the other eye.

Symptoms thus may suggest the cause of the dog eye irritation only if they are throughly observed. However, confirmation of the exact cause should only be made through laboratory diagnosis, as the condition may worsen if it is left untreated for a long period of time.


In order to confirm cases of canine conjunctivitis, the clinical appearance of the eye and conjunctiva is enough. It is also necessary to determine the cause of pink eye in dogs and the exact status of infection, i.e. any chance that the infection will spread to other parts of the dog eyes such as the cornea or parts of the eye ball.

Laboratory diagnosis can confirm the condition, i.e. culturing and isolation of microbes from eye discharge, allergy tests and additional tests for any systemic diseases, since some systemic diseases such as canine lyme disease can cause conjunctivitis as well.


Treatment is based upon a confirmatory diagnosis. Canine pink eye, being caused by several factors including infectious and non infectious factors, thus should be treated specifically according to the exact cause.

In general, if the cause is an allergen, foreign particle, pollutant or any conformational abnormality, it should be corrected. Usually allergens and pollutants are removed from a dog eye through flushing, thus quality flushing solutions, preferably isotonic solutions, should be used for this purpose. Conformational disorders of dog eyelids might require a minor surgical approach, which may or may not need local anesthesia.

Infectious cases of dog pink eye, like those caused by bacteria or viruses, requires the use of antibiotics, which should only be used with a prescription. Local antibiotics for dog eyes are usually available in the form of ointments and eye drops.

In support, to improve eye health and to support vision and the overall physiology of dog eye, natural remedies such as Eye Heal can also be used. These should be administered according to the manufacturer's directions and do not require any prescription at all.