I moved your thread here to our PD forum for more replies.
Members here can help to clarify if it may or may not be PD..

Is your dad still on the dopamine now, or did he stop taking it due to the effects caused?

Sometimes drs will rx it as a test to see how you respond, did he go for a follow up and tell them about the changes?

But if the slow movements and small writing are the main issue they are going by , I would wait on any meds until more clarity of symptoms.. esp when you say his writing has always been small..

I know members here usually suggest a MDS - movement disorder specialist..for best diagnosis.

Also just because they rx a med , doesn't mean you have to try it or stay on it, dependent on the type of med of course, some cannot be stopped cold turkey..

Often it takes many follow ups or phone contacts to get meds adjusted properly if PD is the condition.. it isn't a here take this and see you in 6 months.. you have to let them know what issues are happening..

With all the chiros- did he ever see one that did the upper cervical adjusting?
That might help w/ the crookedness part of things.
www.upcspine.com has lots of info about that.

Feel free to read the sticky threads at top of the PD forum thread list page & browse other members threads while waiting for more replies..
http://neurotalk.psychcentral.com/forum34.html