Stan,
We need more information regarding her drug regime in particular.
Also what does the neurologist you consult with have to say?
Does he have a special interest in movement disorders, in particular P.D.?
A general neurologist in my case knew very little about behavioural changes in a PWP (though this isn't always the case) so the expertise of someone who treats almost exclusively PWP would be good.
There are other causes apart from drugs that could be the cuplrit.
Ask him also if any of the parkinson plus syndromes could be considered or excluded from her presenting symptoms.