You might want to cut the dose in half for a week, then in half for another week, and so on until you get down to a very low dose. Then you skip a day between doses, for a week and finally go off. This is what my doc recommended for getting off drugs you have been on for a long time. You may need to get a pill cutter to get the dose down to a quarter of a tablet, if your pdoc is not willing to help.

You might want to get a migraine med from your regular doc for the headaches. You can get a prn one so you won't be on it constantly.