If your dog's eyelid begins to droop or its eye changes in appearance, it is important to contact your veterinarian right away. Some conditions that appear minor, like a droopy eye, can lead to discomfort, reduced vision or blindness. Your veterinarian will be able to tell you if a droopy eye in your dog is serious or not.
Your dog's eyes should be clear and bright. Dogs have a pinkish or white triangle of tissue that covers the inner corners of their eyes. This flap of tissue is known as a third eyelid and it only protrudes and becomes visible when a dog is sick or in pain. If your dog's eyelid is drooping down when it previously did not or if the third eyelid becomes visible, there is a problem with your dog's eye, according to "The Complete Healthy Dog Handbook."
A droopy eye in a dog usually occurs only in one eye. Your dog's upper eyelid will sag down, hanging lower over the eye than normal. You might notice that the eye waters more than usual or that the inner eyelid is also visible. The pupil of the affected eye might be smaller than that of the other eye. If your dog has a droopy eye, it could also have facial paralysis on the same side as the drooping eyelid.
Droopy eyes in dogs can be caused by a condition called Horner's syndrome, which occurs when an ear infection or a head injury causes damage to facial nerves located near a dog's inner ear. The damage causes one eyelid to droop and the inner eyelid to show. According to the "The Complete Home Veterinary Guide," ectropian is an inheritable condition the causes a dog's eyelid to curl outward. A dog with ectropian will have a droopy eye that tends to water.
Treatment for Horner's syndrome is to treat the condition that has led to nerve damage. If an ear infection is to blame, antibiotics will help clear the infection. A veterinarian can also flush a dog's inner ear clear of blood or pus. You can manage ectropian by keeping your dog's eye clean and clear of debris. In severe cases, a vet can perform surgery to correct the shape of the eyelid and prevent it from curling outward and drooping.
There is a chance that Horner's syndrome will not clear up if the nerve damage is too severe. If this happens, your dog's eyelid will always be droopy and it could have permanent facial paralysis. Your dog's appearance will be changed, but it will still have sight in the affected eye and it will not be in any pain, according to the "Dog Owner's Home Veterinary Handbook."