Horner's Syndrome in Dogs
Horner's Syndrome in Dogs - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Horner's Syndrome?
There are other conditions that produce similar symptoms to Horner’s syndrome. Your veterinarian will need to use observations and testing to differentiate between Horner’s syndrome and other conditions such as uveitis. A neurology specialist may be needed to properly diagnose it.
While Horner’s syndrome can affect any dog, there are certain breeds such as the Golden Retriever and Cocker Spaniel that have a higher incidence of occurrence.
Horner’s syndrome is when the nerves that control certain parts of the eye have been disrupted. The automatic functions between the eye and the brain have become disjointed and therefore, the eye is not functioning properly.
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Horner's Syndrome Average Cost
From 201 quotes ranging from $300 - $2,000
Average Cost
$850
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Symptoms of Horner's Syndrome in Dogs
The symptoms of Horner’s syndrome in dogs are similar to those of other conditions. If you notice any of these symptoms, contact your veterinarian for an exam. Your veterinarian may refer you to a neurologist for further diagnosing. 
  • Drooping of the eyelid on the affected eye
  • Constricted pupil of the affected eye
  • Sunken appearance of the affected eye
  • The third eyelid may appear elevated on the affected eye
  • Vision may be impaired
Causes of Horner's Syndrome in Dogs
Horner’s syndrome in dogs occurs when a nerve going from the eye to the brain has been damaged. There are three things that can happen to cause the damage to the nerve.
Central Lesion
The nerve has been damaged somewhere before the nerve exits the spinal cord. Blood clots, spinal cord tumors, brain tumors or trauma can cause the damage in this location. Other neurological signs may present such as stumbling or head tilting.
Preganglionic Lesion
There has been nerve damage between the spinal cord and the synapse. Trauma to the neck or tumors in the neck or chest can cause the damage in this location.
Postganglionic Lesion
The nerve has been damaged between the synapse and the actual eye. This can occur when the ear is cleaned vigorously or the dog has middle ear disease. Most postganglionic lesions have an unknown cause.
Diagnosis of Horner's Syndrome in Dogs
Most veterinarians will diagnose Horner’s syndrome based on clinical symptoms. Once it has been diagnosed, however, it is important to find out where the interruption between the brain and the eye is occurring. This can be done by your veterinarian or you may be referred to a specialist. 
A phenylephrine solution eye drop will be put in both eyes of your dog. If the affected eye responds to the solution by resolving all clinical symptoms and appears normal, the damage is postganglionic. If the eye does not respond to the eye drops, additional diagnostic testing will be required. Chest x-rays, blood work, radiographs, pharmacological testing on the eye and an MRI are some of the testing that may be required to determine the location of the damage and set a treatment plan.
Treatment of Horner's Syndrome in Dogs
Horner’s syndrome, in most cases, will resolve itself. However, treatment of the underlying disease is essential. In cases of unidentifiable causes of Horner’s syndrome, natural recovery will usually recur within 16 weeks to 6 months.
In the case where there is a serious underlying condition, your veterinarian and your veterinarian specialist will set a treatment plan in place to alleviate symptoms and treat the underlying condition.
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Recovery of Horner's Syndrome in Dogs
Depending on the location of the damage and the underlying condition, if any, recovery time will vary. If the damage has no known cause, it is best to allow the disease resolve itself. This can take anywhere from 16 weeks to 6 months depending upon the severity of the symptoms.
Your veterinarian will give you a better understanding of recovery time once an underlying condition has been found and a treatment plan has been put in place.
Horner's Syndrome Average Cost
From 201 quotes ranging from $300 - $2,000
Average Cost
$850
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Horner's Syndrome Questions and Advice from Veterinary Professionals
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Golden Retriever
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Marley
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9 Years
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13 found this helpful

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13 found this helpful

My pet has the following symptoms:
Droopy Eye
My almost 9-year-old Golden Retriever, Marley, got attacked 10 days ago by another dog, the tip of the left ear flap was injured, he was treated immediately and luckily healed rather quickly with some antibiotics. Around the same time of the injury his left lower eye lid started to drop just a little. At first it was visible only when he woke up or opened his eyes after having them shut, but 3 days ago, the condition started to rapidly get worse, with his eyelid almost always drooping when the eye is open, the third eyelid bigger and pupil decreasing in size. There is even a slight discharge (which he normally never has). The eye also looks a little sunken and watery. He doesn't try to scratch it and there are no other changes in behaviour. The vet did not find any other signs or symptoms when he saw Marley and suggested we could run tests like MRI or CT scan which he did not think were really necessary given that there were no other signs or symptoms. Could it be that it is the injury that caused all this? Do you think we should run CT scans and all other tests? Read more at: https://wagwalking.com/condition/horners-syndrome
Sept. 14, 2018
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Golden Retriever
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Sadie
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7 Years
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13 found this helpful

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13 found this helpful

My pet has the following symptoms:
3Rd Eyelid Showing Red Droopy Eye -
my golden retriever has signs of horners in one eye for a few months now. it has started to improve, no more prolapse of 3rd eyelid drooling stopped and facial droop gone but she still has some facial paralysis on that side, now the other eye is showing the 3rd eyelid - can it switch sides or develop in both eyes my vet initially wanted to wait and see if it improved which it had till today - he said it sometimes takes up to 6 months to resolve on its own and maybe not fully, but Im curious why it is now showing up on the other side - is this possible
Aug. 23, 2018
13 Recommendations
Horner’s syndrome may occur in one eye or both eyes and unfortunately in around 50% of cases (depending on the textbook quoted) the cause is idiopathic which means we don’t know why; the condition can spontaneously resolve in most cases and if an underlying cause isn’t detected we cannot know for sure if it would improve or not. Regards Dr Callum Turner DVM
Aug. 23, 2018
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Yellow Lab
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Ginger
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8 Years
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8 found this helpful

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8 found this helpful

My pet has the following symptoms:
Coughing, Not Eating, Etc
have a yellow lab. She has recently had the signs of Horners syndrome (drooping eye). On top of that she has been suffering from limping(not particularly from pain), coughing, respiratory problems, throat problems, not eating and trouble keeping food down. If anyone has any ideas of what may be causing this, please let me know.
May 30, 2018
8 Recommendations
Many times, Horner’s Syndrome turns out to be idiopathic; however if the limping is in the foreleg of the affected side of the Horner’s Syndrome they may be related and cause by either trauma, thoracic nerve root compression among other causes. I would recommend visiting your Veterinarian to confirm and to determine whether treatment is required or not. Regards Dr Callum Turner DVM
May 30, 2018
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Border Collie
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buddie
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9 Years
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7 found this helpful

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7 found this helpful

My pet has the following symptoms:
Ear Itching
I have a border collie and golden retriever cross. She has all the visuals of Horner syndrome-sunken eye,3rd eye lid, dropping eye lid, and constricted pupil. I took her to the vet who checked for glaucoma,and tears or ulcer on the eye. How long for the eye to get back to normal.treated for inner ear and sinus infection.
March 24, 2018

Answered by Dr. Michele K. DVM
7 Recommendations
Typically, idiopathic Horner's syndrome tends to resolve over a few days to a few weeks. If other causes of nerve inflamation have been ruled out, most dogs have an uneventful recovery. If Buddie does not show signs of recovery within a few days, it would be best to have a recheck with your veterinarian to make sure that nothing else is going on. I hope that all goes well for him!
March 24, 2018
I have a yellow lab. She has recently had the signs of Horners syndrome (drooping eye). On top of that she has been suffering from limping(not particularly from pain), coughing, respiratory problems, throat problems, not eating and trouble keeping food down. If anyone has any ideas of what may be causing this, please let me know. Thanks!
May 29, 2018
Jacob L.
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Pomeranian
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Cody
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Thirteen Years
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
Otitis
Otitis Externa
My 13yr pom X (who also has kidney disease)had a Teca procedure on the 20/12/2017. He also had a tumor removed from the same area. Post op 4 wks and he seems to still cough, after eating and drinking sometimes to the point of vomiting. Sometimes the cough is a long drawn out noise, is this referred to as, aspiration? The side if the head where the teca was preformed, the eyelid still can't close over the eye, how long is long enough before we assume that this function will not return? How long do I wait for the cough to subside before I call it aspiration pneumonia. My dog was given a script for Marbofloxacin which I had compounded to a liquid and administer .7ml daily for 30days to treat bacteria(?) after a sample swab was sent off for a culture report.Is this common after a procedure that I thought would put an end to his non stop cycle of ear infection, antibiotics and ear drops.
Jan. 12, 2018
Answered by Dr. Michele K. DVM
0 Recommendations
Thank you for your email. Without having done the procedure or examining Cody, I can't comment on how long it may take to recover, but nerve damage to the surgical area is possible with the surgery, generally. If he had a TECA procedure, his ear canal has been removed, and any ear infections should be a moot point in that ear. The antibiotics may have been to clear up any infection from the surgery. It is unlikely that he has aspiration pneumonia, but may have a cough for another reason. 4 weeks post op is a long time to still not have eyelid function, and he should probably see your veterinarian for a recheck to assess nerve function to that eye, and to have that cough diagnosed. I hope that he is more comfortable after the surgery, they are often dramatically more happy because their ear doesn't hurt anymore.
Jan. 12, 2018
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pitbull
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Blue
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4 Years
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0 found this helpful

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My pet has the following symptoms:
Frequent Urination
Depressed
Lack Of Appetite
Confusion
Unannounced and unexpected, I saw my dog experiencing anisocoria. He was having accidents in the house and also seemed very off put. Confused, exhausted. He just wasnt himself. I took him to the vet and was recommended he see a specialist. After many tests later, they prescribed him two antibiotics and and anti inflammatory medication for him to take for next 20 days. They warned that the medication would cause him to urinate more frequently. It's almost as if my dog has forgotten he was potty trained. Could there be off set delays of horner's syndrome after trauma? about a year ago, my dog got into a brutal brawl out with another pitbull (my dog is a pitbull). Neighbor's dog trespassed into my backyard and attacked my dog. They both fought almost to death. but there were wounds and punctures in his neck/jugular, face, chest...He recovered. Notes from the specialist given the anisocoria and behavioral issues my dog was experiencing: "On physical exam, Blue seemed depressed. Mildly hypothermic. Left pupil dialated and did not respond appropriately to light. Blood work was unremarkable. Chest X-rays revealed soft tissue opacity that could be enlarged lymph nodes. His opthamology consultation suggested problem was neurological and not opthalmic decease. The neurologist that performed the neurology consultation was concerned about inflammorty CNS decease or potentially cancer." As of current Blue appears to be fine (not getting any worse). He is a little more active at times. more than he was initially. He is still having accidents at the house. I have a feeling that he is going to get better. However, there was no explanation of Horner's syndrome and from what I have gathered. it's what I'm thinking it is... Does anyone know if Horner's syndrome can be delayed after accident (dog fight/attack). Does anyone also know if lethargy/confusion can be tied to it?
Horner's Syndrome Average Cost
From 201 quotes ranging from $300 - $2,000
Average Cost
$850
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