Bulldogs World

My Zimmer has had them for several years. A while back I had some discussions with the AKC Canine Health Foundation & I received this from the vet I was dealing with.

I’m sure it is frustrating for the owners and breeders of these dogs but it does appear to be a fairly benign condition.  So though we don’t quite understand what is going on here, there is not the urgency to get to the bottom of it like there is with the seizures or degenerative myelopathy or any of a number of other diseases that are not so benign. 

We see this type of condition in several breeds, most notably in the bulldogs and boxers.   We used to see drug reaction in Doberman pincers that looked similar but those pretty well died down when the drug in question fell out of use. 

There can be a number of conditions associated with episodes of abnormal movements.  Seizure disorders are the ones we worry most about since seizures can cause brain damage and death if not controlled.  Some focal seizures will cause a head tremor.  Most often the character of the tremor is different from the ones we see in the bulldogs, but occasionally a focal seizure will look identical.  We can determine that something like this is indeed a seizure one of two ways.  If we are lucky enough to see abnormal activity on an EEG, then we can say this is a seizure. Trouble is the abnormal EEG, like the seizures, comes and goes, so it is luck of the draw whether we are recording during an episode.  Also recording EEGs on dogs is easier said than done.  The more common way that we determine a tremor is a focal seizure is when we see it evolve into a more classic, generalized seizure.  If it never does, then we don’t know, but also focal seizures are not as dangerous as the generalized ones. 

The other possibility is that this is one of the episodic movement disorders.  These probably share a lot in common with seizures but arise from a different area of the brain and do not appear to carry the same risks as seizures.  The association with a particular drug in the Dobermans strongly suggests that the problem they had was a movement disorder since that drug is known to produce what are called extrapyramidal side effects in people. 

Finally, there can be many things which can just cause tremors.  We’ve all experienced tremors when we’ve been fatigued or had too much coffee.  Other medical causes are things like low blood sugar or adrenal tumors.

We have done varying degrees of diagnostic tests on some of these dogs and not found any clear explanation for the tremors, which while somewhat frustrating, is in general good news, because we really don’t want to find that these are adrenal tumors or a progressive movement disorder like Parkinson’s disease.  There are things like drug challenges that could be done to help sort out the ultimate cause, but some of those carry a risk of adverse reactions that we always need to weigh into the equation, and since I have not seen these progress to the point where they really interfere with the dog’s quality of life, I’ve been hesitant to take those risks. 

Hope this is of some help to you.  Let me know if you have further questions

Dennis O'Brien DVM PhD

Chancelor’s Professor of Comparative Neurology

College of Veterinary Medicine

University of Missouri