I've been on Cymbalta with Topamax for quite a while. When despression hit hard a few years ago, and nothing else worked without side effects, we went from 60 to 90 mg of Cymbalta--initially proscribed because I suffered to much pain, and it helped with that. pdoc monitored everything closely for months & adjusted Topamax as needed--not all that much.
This has worked well for my BPII for over five yrs. right now I'm going through a period of grief that's not responsive to therapy & pdoc is modifying my meds temporarily.
Best of luck ... demand your pdoc find that best available meds for you ... not just something "good enough" or better than what you were on.