I am on the same drug for chronic diarrhea. It got so bad I felt I could not leave my house. I have never had c-diff and although I was diagnosed with Crohns 50+ years ago, I have been on no medicine and healthy. My problem was the diarrhea from having all but 9 inches of my colon removed 50 years ago. Cholestrymine keeps it to a manageable level. BTW it was an internist, not a gastro that prescribed it and saved me.