Anecdote: two people close to me have undergone cholecystectomy, and both developed IBS-D shortly following the operation; cholestyramine (essentially a powdere

Anecdote: two people close to me have undergone cholecystectomy, and both developed IBS-D shortly following the operation; cholestyramine (essentially a powdered resin that absorbs bile in the the GI tract) proved to be a safe treatment. It seems that removing the gallbladder didn't make things worse on the whole - the symptoms of biliary obstruction were far worse than diarrhea or the daily requirement to consume orange-flavored plastic dust - but it did reveal an underlying excess of bile production that would irritate whatever it could downstream. I would be interested to know what caused that in the first place, and if it could be treated non-surgically.