Ask your doctor about cholestyramine powder. It's a prescription, at least mine was. Also, everyone else's comments are very helpful--what you eat obviously has a huge impact. I'm sure you are trying yoghurt, probiotics too if the doctor OKs those. And watch out for coffee--
I hope his weight is not going down too rapidly; that was a major issue for me. Actually, having the surgery makes it worse for a while--over a year and a half and I am now fairly normal.
Mine was not as frequent or runny as his, but I take no drugs including Creon. I read the info on Creon that comes with it and it looked like it could cause the very thing that I was trying to prevent. Antibiotics as well make things worse. Sometimes I think the scalded milk I got as a child for diarrhea works better than the modern way with more drugs. Sorry, my attitude towards more drugs after more drugs is not good! How about peppermint tea and lightly buttered toast for a while? The Old Grump, Carrie (This is a serious issue and I am not making light of it. My best wishes for your husband--this situation is dire for lack of nutrition, dehydration, etc and just general exhaustion. It was my young female PC that prescribed some actual, no side effects help, not the oncologist, the radiologist, the dietician, the urologist, the ophthalmologist, the dermatologist, the counselor, etc etc. It does get to be a bit much--as all of you know.)