I've had an upset stomach/diarrhea for the past two days off and on. The diarrhea isn't a lot but just 2-3 times a day but mainly the upset stomach is always there. My dr recommened I take kaopectate or immodium for the diarrhea. Immodium does not work for me...it does the opposite which I was just getting over anyway. My question is why is it ok to take kaopectate but not pepto-bismol when they contain the same active ingredient bismuth subsalicylate?