Details Bacteria is a leading cause of diarrhea and it can come from the food that you eat! Pepto Diarrhea gets to the source with its DUAL ACTION formula that COATS your stomach and KILLS BACTERIA THAT CAUSES DIARRHEA. When left untreated, bad bacteria can continue to grow. Pepto Diarrhea Liquid provides fast and effective diarrhea relief and is 3x more concentrated than Pepto Bismol original liquid per oz. Take Pepto Diarrhea at the first sign of diarrhea so you can get relief! From the maker of the #1 Pharmacist Recommended Upset Stomach Brand - Pepto Bismol (based on Pharmacy Times 2018 Survey-upset stomach remedies category). May be HSA/ FSA eligible.