Canine Tip of the Day: HORNER’S SYNDROME

It has taken me every single moment of the last 6 weeks to be strong enough to put this blog together for you.  I say that because it was the key component to the downward spiral that eventually lead to the loss of my darling Chi.  I will try to write professionally and sensibly, but please indulge me if it feels a little to close to home.  Everything I write and document is purely for the betterment of your knowledge and hopefully a tiny glimmer of hope from a heart-breaking chapter.

6 weeks ago, Chi, my 7.5 year old Ridgeback, first aid partner in crime, son of Axl and total light of my life was fine and dandy – or so I thought.  We’d had an entirely normal day, with a normal walk, normal play and normal evening.  At 9 pm on Monday night, he woke from a nap and turned to look at me.  When he did, he just didn’t look “right”.  Something was off in his appearance as if his third eyelid wasn’t going back into its normal position.

Third Eyelid Showing

I called him over to me so that I could have a look at him and as he got up, he limped very badly on the same side as the droopy eye – how very odd!  Prior to this, he had been totally fine and had exhibited no signs of any problems whatsoever but now, after a quick nap, he looked decidedly squinty and lame.

When two brand new symptoms happen with absolute synchronicity, and seemingly no outward cause, you have to suspect them to be connected.  By the Tuesday morning, he was still limping and still squinting.  I checked him over head to toe looking for an injury to shoulder, elbow, foreleg, toes … anything at all that would give me a clue, but he showed no outward signs of pain.  I was just about to give up on the exam when my fingers accidentally slipped inside his armpit, ever so gently as I stroked him.  He shrieked!  Wow … I did not expect that!  I had hardly touched him and yet his howl was that of an animal in excruciating pain.  So, an appointment was made for him to see our vet later that afternoon with my “home diagnosis” of Horner’s Syndrome but, try as the vet might, Chi refused to show any pain to him on examination, although he was still squinty and lame.

We decided to treat with pain killers and anti-inflammatories.  If it was something like an ear infection and pulled muscle, these should help with the pain and we should see a definite improvement.  If it got worse or didn’t start to improve by the following week, we were to proceed to x-rays to check him out more thoroughly.  However, the following day, he was clearly in more pain and more uncomfortable.  The meds were just not touching it, so the x-rays were brought forward and booked for the following day (Thursday) with a worrying consideration being given to the very real possibility of bone cancer.  The x-rays were done but these all came back clear – nothing to be seen skeletally and no signs of spread to the chest either.  I was delighted, thinking we had dodged a bullet.  It was decided that he should be referred to an orthopaedic specialist with a provisional diagnosis of a neurological issue.

On Friday morning (3.5 days after the initial symptoms), we arrived at the Specialists office – me still naively thinking it could be a trapped nerve in the spinal vertebra or perhaps an exploded disc (horrid, but operable).  Sadly, my hopes were dashed very quickly indeed as the consultant easily diagnosed a tumour of the brachial plexus (for those geeks among you, the brachial plexus is a network of nerves that extends from the spinal cord, through the cervicoaxillary canal in the neck, over the first rib, and into the armpit).

The options were either CT & MRI & amputation of the foreleg & then chemotherapy with a prognosis of a matter of months …….. or, Rainbow Bridge.  I could never subject my darling boy to that.  I couldn’t put him through the prodding, poking and being away from me, which he would have hated beyond words – only to have another couple of months, throughout all of which he would have been recovering from surgery and undergoing chemo.  I had to let him go.  We shared an emotional half an hour of hugs and cuddles and apologies and promises and then he fell asleep in my arms being told how much I loved him.  My darling boy was gone and there was not a damn thing that I could have done to change it.  I was, and am, devastated.

So here we are, 6 weeks on, me in floods of tears as I write and relive this, and still aching inside to have had to say goodbye so early to the sweetest, gentlest, golden lad – just two weeks after the birth of his first puppies who he never even got to meet.  But … if there can be anything at all to be salvaged from his passing, I will grab it with both hands and thus why I’m tell you all about Horner’s now.

Horner’s Syndrome doesn’t always mean your path will go like ours – in fact, it often resolves spontaneously without any intervention at all, but I’d like to tell you a little more about it because the more you know, the better prepared you are to act quickly and get treatment when you really need it.  Had I NOT have known what it was, I may have left him on lead/crate rest, dismissing the eye as tiredness and the limp as a pulled muscle.

If after pouring my heart out and destroying you all emotionally too, you are still reading, then this is the information you need about this Horner’s … courtesy of Chi, my ginger hero.

Chi enjoying some downtime in Scotland



Firstly, let me say that Horner’s Syndrome is very common.  Its onset, as with Chi, can be very sudden and entirely unexpected.  This Syndrome is often classified as idiopathic, which simply means we are unsure of what the specific cause is.  (It is, however, very important to get to the bottom of it so that that underlying cause can be treated).

What is it?
It is a combination of signs and symptoms caused by a disruption of a nerve pathway that goes from the brain to the face and eye on one side.  Usually, you will only see signs on one side of the face but very rarely it can affect both sides if both hemispheres of the head are damaged.  This Syndrome can affect any breed and any age of dog, though it is perhaps a little more frequent in Golden Retrievers and Collie breeds.

Signs & Symptoms
Droopy eye lid
Third eye lid may look red, raised and coming partly across the eye.
There may be sinking of the eyeball on that side
Decreased pupil size on the affected side
You may notice increased salivation
You may notice the dog has difficulty eating on one side of his mouth.

There can be many causes but generally they are connected with injury to the sympathetic pathway through the chest and neck.  Those causes could be:

*Bite wound
*Blunt trauma such as a barging injury through rough play or RTA
*Intervertebral disc disease

Other causes to consider would be infections to the eye, the middle or the inner ear – hence why this can be quite a common thing when we take into account the number of ear infections our floppy-eared dogs can have!

Although this Syndrome is one that will resolve spontaneously, we need to get to the bottom of the underlying cause and it is usual to opt for such procedures as:

*eye examination
*ear examination
*chest x-ray
*skull x-rays
*possibly also MRI and CT imaging.

Recovery from the Syndrome itself is usually spontaneous taking anywhere from several weeks to around 4 months – provided that the cause is not pathological.  If there is no underlying pathology (such as a tumour for example) then the outlook is very positive indeed.

Night night, sleep tight Chicky Chi Chi …. mammy will ALWAYS love you xxx


  1. Reply

    Good night sweet Chi, thank you for your teachings. May you spend time weaving, as only you could until you get to see your mammy once again. You will always be much missed xx

    • Reply

      Thank you Trudy, he’ll be up at the Bridge with Axl causing havoc, chasing deer and weaving his heart out like only Chicky could. Im so pleased you had the pleasure of meeting him. xx

  2. Reply

    so sorry, and thsnk you for posting. ive kearnt something. but more importantly i just want to reach out with a big hug….
    no other words…

    • Reply

      Thank you so much for your kindness – it’s nice to know we are all connected at such sad and trying times. xx

  3. Reply

    My heart is breaking for u. Thank u for the generosity of heart and the courage it took to put this information together that others of us might learn from u. I know my Simba must have met your beautiful Chi as he crossed the Rainbow Bridge, and that they replaying their hearts out in beautiful fields just patiently waiting to see us again.

    • Reply

      Im absolutely positive Ted – they deserve to be happy as only truly golden innocent souls can. Until we meet them again, Im sure they’re watching over us x

  4. Reply

    So sorry for such a devastating loss. We lost our Red (6) to GDV (gastric torsion) this year and went through similar processes of investigation, help, even operations and finally, the inevitable decision. I feel our pain when I read of yours. Nothing can describe the loss of such incredible dogs and the bond we are privileged to share with them, even for such a short time. Thank you for sharing.

    • Reply

      My heart is aching, as is yours, but we were truly privileged to have been their guardians and to set them free when there was no other alternative. All my love Jenny x

  5. Reply

    Bless you, Kerry for using your grief energy to help others – you honor your Chi’s spirit.

    • Reply

      Chi was a born teacher … he did his first class at just 6 months old and loved it every single time. He has met thousands of students and I like to think that at least he could teach one last lesson even in his passing. I was so blessed to have had him in my life, and so pleased that he got to meet so many wonderful people in his life. His puppies flew the next and went to their new homes and families today … I know they will bring as much happiness as Chi did to me. The gift and legacy he leaves is my biggest consolation. He was … priceless xx

  6. Reply

    Oh my, I’m just so sorry for your loss, how truly heart breaking for you. You’ve done one of the most hardest kindest things you’ll ever have to do in letting your beloved Chi pass over the rainbow bridge.
    I came upon your site while looking for natural nettle sting cures and stopped to have a look around and that’s when I read about Chi. I’ve had a good cry and know you’ve done the only thing you could have done and I’m sending you virtual hugs and the time to heal that you will need xxxx

    • Reply

      Thank you Sara … it truly is heartbreaking to lose them and to lose them so early is just tragic. To be honest, forever wouldn’t have been long enough xx

  7. Reply

    Thanks for the information Kerry. Heartbreaking. I think you did the right thing for Chi. We had unexpected cancer in the bones of our 8 year old RR (Cass) at the outset of lock down and I had to put her down a few weeks later when I could see it was the right time. After a long search we will pick up our new RR gal in mid April 2021.

    • Reply

      Aw Andrew, Im so sorry to hear about Cass … forever would never be long enough, but 8 certainly isn’t enough is it. We have to do the right thing – as unpalatable as it is. We love them from the first to the last. Im excited for you getting your new puppy in April. Our new “whirlwind” Coda is now 15 weeks old and he has really helped to lift the black cloud from our family. Wishing you all the love and luck in the world with your new girl … check out our Puppy First Aid Video in the shop 😉

      Best wishes

      Kerry xx

  8. Reply

    I stumbled across your blog while searching for canine 1st aid courses and felt soovrd I needed to reach out. I also very sorry for the devastation that the loss of Chi clearly was for you but want to thank you for your bravery and honesty in sharing. What a wonderful way to honour Chi. I have always admired ridgebacks (Im a rottweiler Mummy) and he was a stunning example of the bread.
    A friend and fellow rottie owner lost her girl last year after a diagnosis of MMM but reading your blog, I wonder if it was undiagnosed Horner’s – I guess we will never know.
    Run free at Rainbow Bridge Chi, until you are reunited with your earthly family once again

    • Reply

      Oh Karen, thank you so much for your lovely words – brought a tear to my eye I must admit. Losing them at such a young age is just tragic but if even one person is helped because of him, then it wasn’t all wasted. Thank you for reaching out … it makes my job worth while and I wish you many many happy years with your Rottie crew! If there is ever anything we can help with, please just shout. Our first aid courses are continuing online for those who need them that way but I am glad to saw we are now also able to get back out on the road delivering our courses in person. Our Scottish tour will start on 15th April … just putting the dates together and they’ll go live for booking very soon.


Leave a comment

Your email address will not be published. Required fields are marked *