I have AFib and have been taking 120 x2 slow release capsules of Diltiazem for over 7 years with no severe side effects. However, intermittently (4 or 5 times a year) I experience diarrhea and vomiting for no apparent reason. I first thought it was the Warfarin (Cumadin) but I had an episode after stopping the Warfarin. Has anyone else had a similar experience?