Many epileptic dogs are well-controlled on anticonvulsent medication. Best of luck with your puppy. This produces progressive widespread nerve degeneration. I have seen reports of this rare condition in cats, but not in dogs. The symptoms described in one Siamese cat were rear leg weakness progressing eventually to affect the forelegs as well.
Definitive diagnosis involves complicated enzyme tests.
I have never encountered this condition in almost 30 years of veterinary practice.