What can cause a pseudo narrowing of colon? and what would be the treatment? fiber supplements cause more mucus in stool and irritate me more.

Hard to say: Hi JonT, Sorry to hear that you have been feeling poorly. I think this is a topic better discussed in depth with your primary physician. "Pseudo narrowing" is a little bit of an ambiguous term and requires some clarification from your doctor as to what exactly they mean when they say pseudo-narrowing. Further testing may be needed to determine if you have an actual stricture. Hope this helps.