Thank you for the reply.
Leg tremors are something that we see quite regularly, but very rarely do we work up or treat for that matter because in most cases, as you have stated, they don't affect them when they walk or otherwise use the leg. They really tend to be more noticeable when the dog is not moving or is excited. My own dog experiences these and they are most apparent when she is watching me cook and hoping something will fall on the floor.
Limb tremors can be secondary to degenerative, metabolic, inflammatory/infectious or cancerous conditions or can be an idiopathic (unknown cause) tremor as described in people.This is referred to as essential tremors and are one's that happen at rest more than during movement. As you can see, the spectrum of causes is wide open and the only way to definitively confirm essential tremors is to rule out all of the other causes. This can be quite exhaustive when it comes to testing for every possible disease condition, so what we usually recommend is at least a thorough physical exam and bloodwork and full neurologic evaluation, including checking all of the nerve reflexes. If nothing out of the ordinary is noted with this work up, we are usually content to call theses essential tremors, unless other neurologic changes show up down the line.
In Forrest's case, I do not believe his enlarged heart is likely related. In fact, in this breed, many times their heart can appear enlarged on xray and it is a normal finding.
As far as treating this condition, unless it is so severe so as to be bothering them, it is usually not treated. When it is, the drug called Gabapentin, given at a low dose, is often very effective to help decrease the severity of the tremors.
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