I have no experience with seizures in dogs, thank goodness, but have read up on it some. Just saw that it can cause an increased appetite and water intake. Did not see anything about whining but said it can cause anxiety so possibly that is what you are seeing. Also said symptoms should improve within 7-10 days. Sorry I can't offer more advice. I am sure the Neurologist will be able to help you out more, I hope.
Good luck and please come back to update.
i just had my dog put on phenobarbital for seizures and he won't stop whining and it sounds like a pretty common side effect that will go away after they get used to the medication.
My German shepherd has been on PB for two days. She has fallen while standing still, whines, is restless, and is getting into the garbage cans, which she never does. She's also having accidents even when the door is open. I have read, and hope it's true, that all this may diminish as she adjusts to the drug. It's better than her seizures.