"Bismuth subsalicylate is an older drug, and is less effective in some studies."
I don't argue with RN's or Physicians, both have different training than I do. My only argument with Loperamide is, as I understand it, it effectively paralyses the G.I. tract; trapping any microbes in the gut. Pepto Bismol slows but doesn't stop peristalsis. If a person has food poisoning or some similar problem, they may continue to feel sick until the causitive agent is expelled from the body. That may take longer if the person has taken Loperamide. But I don't argue with R.N.'s