Effective Natural Remedies for Managing Diarrhea

I have suffered from chronic diarrhea for sixteen years due to having Crohn's disease. I read on your site about using cayenne pepper for this. I went to GNC and bought cayenne pepper capsules and it is working great. I am concerned though that this may cause ulcers? Also, I have a colonoscopy scheduled soon and the bottle says to stop taking two weeks before surgery. I am wondering if that would apply to my procedure as well. I also wonder why I should stop taking it before surgery.