Idiopathic head tremors

Words: Serena Henderson

Idiopathic head tremors were something I had never experienced until a dog came into my life that suddenly developed them. Our rescue dog named Thea was 10 months old when she had her first tremor. I remember her lifting her juddering head to look at me from where she sat on the sofa; it wasn’t the tremor that had disturbed her but the opening of the food cupboard door! She didn’t appear to be in pain and she wasn’t frightened; she was fully conscious and unperturbed by the head bobbing.

From social media and browsing dog groups (probably more than I should), I have encountered posts and video clips from many distressed owners. The initial experiences that dog owners have leave them feeling very frightened. Indeed, an idiopathic head tremor can appear to be very ‘seizure-like’. Questions like “Is this normal?” and “What should I do?” often arise, and amongst prone breed groups there will usually be a number of other users whose dogs have experienced them as well.

An idiopathic head tremor (IHT) is a spontaneous rotational, side to side (‘no’ motion) or up and down (‘yes’ motion) of the head in rapid succession. The term ‘idiopathic’ denotes that the condition is both spontaneous and without known cause. Whilst the tremor itself can appear like a seizure, it is theorised as being a type of dyskinesia triggered by the basal ganglia, which are islands of grey matter deep within the brain. These neurone clusters are key messengers responsible for movement and a wealth of other cognitive functions. During these episodes, the dog remains conscious, alert and responsive, seemingly unaware that the tremor is taking place.

Bulldogs, Labradors, Boxers, Dalmatians and Dobermans are all breeds prone to IHTs, although some other breeds and occasionally cross-breeds can also be affected.

Researchers have found that in some instances it could be hereditary; with the Doberman, it has been traced back to a single sire. Other suggestions that may or may not be contributing factors include hormonal changes like those seen in pregnant and lactating bitches, low blood glucose or calcium levels and emotional states of high stress, overexcitement or mental trauma. Interestingly, studies have found that an abnormality in the stretch reflex mechanism could also be a cause.

Head tremors are most likely to begin in a dog that is between 6 months to 3 years old, although they can present themselves at other life stages. If left without interruption they can last for approximately 5 minutes, but are often much shorter. Veterinary diagnosis is difficult but necessary and will rule out any serious problems. The diagnosis will generally involve a process of elimination, taking factors such as breed, age, medical history and outside influences on board. At this point, any recorded footage you can provide of the episode taking place can prove extremely helpful. Your veterinarian may also ask you to keep a diary of the frequency and duration of episodes. I have found that keeping such a record is a fantastic way of monitoring the tremors. Doing so might just give you some insight into potential triggers and will provide a wealth of information should it suddenly become required.

Whilst at the vets, a physical examination of your dog should be expected and vital signs will be recorded. If there is any doubt, additional testing should not be ruled out and this can include an MRI scan of the brain and CSF testing of the cerebrospinal fluid to check for any neurological abnormalities. A veterinarian will also be looking out for other serious conditions such as infectious diseases or toxicity from things such as poisons or environmental pollutants like agricultural sprays.

As IHTs are of unknown cause and considered harmless, treatment for them has been ineffective and/or deemed unnecessary. The most effective way of bringing the dog out of an episode has been found to be distraction. When our own dog is in the middle of an episode, offering a delicious treat always stops the tremor from running its full course. A 2015 study of 291 affected dogs carried out by the Veterinary Information Network found that, in addition to treat distractions, using other methods to turn the head such as calling the dog’s name or making a noise also concluded the episode. You may also like to try asking the dog to perform a task to move them out of the tremor too.

The frequency of tremors can vary greatly from dog to dog. My own dog experiences her tremors three or four times some months and then a few months may pass where she does not have any. Throughout her adolescence and now as an adult, the frequency has neither increased nor decreased. In my canine social circle, I have found that experiences of frequency can vary greatly. In some instances, the tremors have completely ceased with age. However, if your dog starts to have tremors that last longer than usual, or if there is a big change in their frequency or if the dog starts to exhibit behavioural changes, then a trip to the vet is paramount.

There is no evidence to suggest that IHTs have any effect on your dog’s lifespan; it is a benign condition that can suddenly stop as quickly as it started. Studies have not found any links to long-term illness or disease. Breeding from affected dogs is strongly discouraged.

If IHTs are considered harmless, then why are they still so worrying? Nobody likes the idea of a ‘cause unknown’ disorder and there are still areas that I’m sure need investigating and that will be the subject of further study in the future. For now, support groups can be found on social media for you to share your experiences and be in the company of other concerned owners – although every dog should be dealt with on a case-by-case basis, so always seek guidance from your veterinarian first.

Thea came from a litter of nine and it’s lovely that we have all stayed in touch. It’s been a joy to watch the other puppies grow and at two and a half years old, she is the only dog in the litter to be experiencing IHTs. Both parents are also in wonderful rescue homes and are additionally clear of any physical signs. In our case, her tremors have become no more frequent than the day they started and she continues to thrive in just the same way as her siblings.

So, until we are advised of a better solution, we have found the most effective treatment for our dog to be the humble dog biscuit – and she seems very happy with the extra spoils.