I was on the maximum recommended dosage, first of Cymbalta, & then of its generic equivalent when it became available several years ago now. I had previously been on Prozac & Paxil & a few other things I can't recall the names of.
For me... Cymbalta was the best antidepressant I ever took. Even though I was on the maximum recommended dosage, I experienced almost no side effects. And along with helping me with depression, it also helped with the low back pain I've experienced for years. The one thing I did notice, toward the end of the period of time I was taking it (a year or two... memory fails me) was I began to notice some jerkiness in my hand & arm movements. This went away as soon as I was off of the medication.
I finally decided to go off of the medication when I changed health insurance plans & the out-of-pocket cost skyrocketed. I went in to see my pdoc to seek his advice. He gave me a withdrawal schedule that took me from the maximum recommended dosage down to zero over the course of two weeks. I had read horror stories about people trying to come off Cymbalta. So what my pdoc recommended seemed very fast. But since that was his recommendation I went with it & had little or no difficulty.