I was recently diagnosed with IBS-D. My psychiatrist (I am in a hospital) started me on Zelnorm right away. I read up on it and learned that it is best for patients with IBS-C and IBS-M, and that it should not be started on patients with predominant diarrhea. I raised my concerns and they said that it would be better for me -as opposed to Bentyl- because it has fewer and less serious side effects. I agreed after looking at the side effects of Bentyl and realizing it had some of the same side effects of Reglan. I took Reglan a couple of months ago, before I was diagnosed with IBS and before I had ever had a colonoscopy and endoscopy, and suffered some of the more serious side effects-psychosis being one of them. So I opted for the Zelnorm. I have been on Zelnorm for a week now and the diarrhea has not improved. However, I have not really noticed it to be worse. My question is this- Should I ask for a different medication since this is not helping? Or have I not given it enough time? I would hate to switch to the Bentyl and take the chance of suffering the side effects that may or may not occur. But I also am not having any relief. I also was just diagnosed a week ago (same day the Zelnorm was started) and have just had the last few days to learn about IBS and how to manage and cope with it (which I am still learning). Any advice would greatly be appreciated.