Kortneypac is spot on, but I would like to add to it. First, I have CRPS. Second, fentanyl is, in my opinion, I am not a doctor, 100% wrong for CRPS. Any doctor who knows CRPS, would not have you on it.
The meds kortney suggested are where you need to be.
And, I highly suggest, LDN, low dose naltrexone. This an off label use if naltrexone. When researching, be sure to look up low dose naltrexone, not just naltrexone.
Of course, we are all different and you might a different blend of meds than me, but look into all of these.
And for your well being, get a Doctor that knows the disease. Please, I cannot stress this enough, but take charge and be your best medical advocate.
I have a hub on the subject and
I have a blog, please read it, I am willing to help in any way I can