Dee,
I don't have any experience with Vidaza myself, but you can read what some others have said about what it's like to take this treatment in the forums (search for posts about "Vidaza" by clicking on the triangle next to word Search in the gray bar at the top of this page).
Vidaza is given in cycles so I think patients feel ok at first and get gradually weaker during the cycle. You'll probably have to see how it goes for your father but having someone with him until you know how he reacts is probably a good idea.
I see that you are in Missouri. When your father is ready, you might consider going to the
Siteman Cancer
Center at the Washington University for a second opinion.
Let us know how it goes for your father.
Regards,
Ruth