I'm currently taking Cymbalta and experiencing the diarrhea. It's been working wonders for my depression and anxiety, keeping my moods stable, but having to run to the bathroom to evacuate so frequently that my food is not fully digested is pretty rough some days. I had taken Cymbalta before, in high school with no trouble, then again in college. That was before it went generic, and my health insurance wasn't good, so I only took it for a month, but continued to have the diarrhea for another year. I think it flushed out all my healthy gut flora, because as soon as I started taking probiotics, it was like night and day. Well, I'm taking probiotics now, to no avail. I also had my gallbladder removed four months ago, but hadn't had much in the way of bowel trouble until starting the duloxetine again. I'm reluctant to switch to a different medication because I've tried quite a few with differing results, and apart from the diarrhea, it's really made a difference in my mood and ability to function.
Anyways, I guess my advice if you've stopped taking Cymbalta and are still having diarrhea or other digestive issues, look into probiotics. There's an incredible amount of research going on right now into the biome of the human gut, and a lot is happening in the world of probiotics.