1 Important Caveat to Horner’s Syndrome in Dogs

Horner’s syndrome in dogs is scary to see and is sometimes mistaken for a stroke. I would be shocked if my dog’s face and eyes suddenly went slack!

Half of the dogs diagnosed with Horner’s Syndrome have no underlying cause (idiopathic).  Unfortunately, that leaves the other 50% with deeper issues, which I will be talking about in this article.  Horner’s syndrome on it’s own isn’t a big deal. The number 1 caveat is the diagnosis of any underlying disease.

Scroll down to read about acupuncture to treat Horner’s Syndrome in dogs.

The Experience of Horner’s Syndrome in Dogs

Horner’s syndrome in dogs is similar (but not exactly the same) to Bell ’s palsy in people. In Bell’s palsy, the 7th cranial nerve is damaged. It causes temporary facial paralysis and only affects one side of the face.

In both cases, there is a disruption or injury to the nervous system. In other words, something misfires (or interrupts) the electric pulses that control the eyes and facial muscles.

In the following YouTube video a 17-year-old dog is treated with acupuncture.

Horner’s syndrome happens quickly. It is common to some dog breeds including golden retrievers and cocker spaniels.   Clinical signs include:

  • Head shaking
  • Head tilting
  • Possible pawing at the face
  • Droopy eyelid (clinically called “ptosis”)
  • Constricted pupils (clinically called “miosis”)
  • Third-eye (the membrane/film located in the corner of your dog’s eye) becomes inflamed and red.
  • Eye appears sunken
  • Drooling
  • Trouble eating out of the side affected

No Known Cause in 50% of Dogs

An experienced veterinarian will recognize the signs of Horner’s Syndrome.  Diagnostic tests will determine whether there is an underlying condition causing the syndrome.

If you look hard, you’ll see this dog’s eye appears sunken (his left eye).

50% of cases will be idiopathic, meaning no cause was found.  Other dogs could have any of the following issues:

  • tumor

Tumors of the spine or head.

  • tetanus

Tetanus, also known as Lock Jaw, can cause the symptoms of Horner’s Syndrome.

  • intervertebral disc damage

Disc damage from car accidents, falls from a distance, and animal abuse, to name a few.

  • bite wounds

Bite wounds to the neck or head can damage nerves causing symptoms of Horner Syndrome.

  • head injury

Any type of head injury could trigger Horner’s syndrome in dogs. Car accidents, rough play, and an object falling on the head are some reasons for head injury.

  • middle ear infection

Middle ear infections affect people and dogs. They cause pain and inflammation. The inflammation can be a trigger that interrupts nerve activity.

  • central lesion

A central lesion occurs when a nerve is damaged before leaving the spinal cord.  Causes for central lesions include blood clots, tumor, and trauma.


  • postganglionic

Neurons live outside the central nervous system within the actual cells. If your dog has nerve damage, it is considered postganglionic because of the affected nerve cells.

  • preganglionic

Neurons operate within the brain stem. If you dog’s underlying condition is a tumor, for example, it would be considered preganglionic.

I Didn’t See it Coming

It’s important to remember that injuries and trauma could happen to your dog without you even realizing it.  I often see people driving with their dogs in the back of their pickup. One sudden need to brake and those dogs could be in trouble. A sudden neck jerk, fall, or cranial impact could trigger Horner’s syndrome in dogs.

No Treatment Needed for Horner’s Syndrome in Dogs

Horner’s Syndrome does not require treatment; however, any underlying causes do. The veterinarian will make a fast diagnosis based on the dog’s appearance. To rule out conditions such as hypothyroidism or tumors, the doctor will order clinical tests.

Treatment plans focus on underlying illnesses.

The Time Line from Start to End

If no underlying disease is found, it could take your dog anywhere from 16 weeks to six months or longer to fully recover.

Healthy dogs with no underlying disease fully recover within seven to eight weeks.

Pin Pointing the Benefits of Acupuncture

Acupuncture is a means of helping the body heal itself faster by correcting imbalances.  Dogs with Horner’s Syndrome benefit from acupuncture applied twice within two days.

Acupuncture in dogs works by improving blood circulation. The stimulation of the nervous system and the release of “feel good” hormones work together to correct imbalances. A qualified veterinarian professional applies small needles where nerve endings and blood vessels meet in the body.

Other Acupuncture Available for Dogs


The certified veterinarian acupuncturist uses pressure on appropriate points. This creates a response similar to acupuncture within the nervous system.


A heated herbal compound is applied to pressure points.


If you’ve ever had a TENS system applied to your back, you’ll have a good understanding of what this feels like. Essentially, a small electric current enters the body and relaxes muscles.


Laser energy is used on specific pathways the same way traditional acupuncture would, but without the needles.

When a dog receives acupuncture to relieve the symptoms of Horner’s Syndrome, the following pathways are used:

ST-4 Meridian (Di Chang).  This pathway travels around the mouth and lower cheek, through the diaphragm.

GB-1 Meridian (Tong Zi Liao).  Known as the gall bladder meridian.

The Results Are In

Anecdotally, through forums and social media, dog owners rave about the good results their dogs have had with acupuncture treatments. 

The National Center for Biotechnology Information published a systematic review that included the culmination of information from studies, reports, articles, abstracts, conferences, and expert interviews.  The topic was whether acupuncture is beneficial to animals.

The results of the study landed on neutral ground citing no real evidence for or against acupuncture in dogs.  

Getting an Accurate Diagnosis – The 1 Caveat

The most important thing is to get an accurate diagnosis. As mentioned above, Horner’s Syndrome in dogs isn’t a big deal, but it could be if there are serious underlying causes.  Your dog might be at higher risk if he/she is diabetic. It’s those causes that need to be discovered so that your dog can be effectively treated.

The infographic below, obtained from the Visual.ly content gallery, explains how acupuncture works.

How acupuncture works Infographic