Horner's syndrome in dogs is a common disorder causing issues with the eye and vision in general. Pet owners should be aware of this condition and know what to do if they spot clinical signs of it, especially if they own a golden retriever or cocker spaniel, as these breeds have slightly higher incidence rates.
Clinical signs of Horner's syndrome typically revolve around the eye area, although the dog may also begin to salivate excessively, according to VCA Animal Hospitals. Owners should look for a drooping eyelid, constriction of the pupil, sunken eye or a protruded third eyelid. The eye tissues may also appear red. Horner's syndrome often appears quite suddenly and most often only affects one eye.
The good news for owners is that Horner's syndrome will likely improve over several weeks, assuming there is no underlying cause for the issue. Still, pet owners who suspect their dog has Horner's syndrome should take their animal to a veterinary clinic to be checked out. Several diagnostic tests should be performed in order to determine if there is an underlying problem such as dehydration, inner ear disease, nerve damage, disc problems, facial paralysis and more. It's also possible that a bite or blunt trauma can trigger Horner's syndrome, so owners should let their veterinarian know if this is a possibility.