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Canine Keratoconjunctivitis Sicca (KCS)

Dry Eye

Tears are essential to keeping the eyes moist and healthy by transporting oxygen to the eyes and removing waste. Tears have three portions: water, oil, and mucus.

Keratoconjunctivitis Sicca (KCS) is a common eye condition where the tear glands do not produce enough of the water portion of tears. Therefore, there will be a yellow discharge on the eyes.

This also causes eye irritation, inflammation of the cornea, and possible blindness.


Most commonly, KCS is immune-mediated: the immune system attacks the tear-producing cells.

Other causes include:


Both eyes are usually affected with signs such as:

If you notice any of these signs, bring your dog to the veterinarian right away. Prolonged dryness of the eyes may cause scars on the cornea, which can lead to blindness.


The main diagnostic test your veterinarian will do is the Schirmer Tear Test:

Your veterinarian may perform other tests to rule out other conditions:


Treatment of KCS is a life-long medication routine. In most cases, this stops the immune system from attacking the tear glands, and stimulates tear production, protecting the cornea.

If your dog does not respond to medication, your veterinarian may recommend surgery. A saliva-producing gland will be attached to the eye to lubricate it. This may cause excessive tearing.


There is no known prevention for KCS.


With life-long medication, there is a great prognosis.

However, if there is considerable scarring on the cornea, your dog may never regain full vision.

Medically Reviewed by Sara Ochoa, DVM

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