While researching for my book I came across a term I had never heard about, called Habba Syndrome. You can read more about it at: http://habbasyndrome.com/_wsn/page2.htm
According to Dr Saad F Habba, a dysfunctional gallbladder releases excess bile. This in turn leads to urgent diarrhea, particularly after meals. The treatment is taking cholestyramine (Brand name Questran) daily. It effectively binds the excess bile salts, reducing the amount of diarrhea.
There is not much information available on this syndrome, so it is is difficult to ascertain whether or not it has been accepted by the medical community, the gastroenterologists in particular. For those with chronic diarrhea, sometimes anything is worth a try!