Coffee enemas can be incredibly helpful and they do not harm the gut at all when done properly. It's listed as a detox suggestion here:
www.tiredoflyme.com/detox-methods.html Unfortunately, I don't know a good site that has instructions for this, although I'm sure there are a few out there. I don't do them because they would set off a week long intestinal cramping episodes for me.
I do know that it helps eliminate a lot of toxins in the intestinal tract as well as seriously increasing the glutathione production from the liver for a short time.