<unk>  is a OTC antacid that is FDA approved for the treatment of diarrhea, heartburn, indigestion, nausea, upset stomach.   Common adverse reactions include darkening of the stool and/or tongue.
Bismuth subsalicylate
Hexetidine
Aluminium hydroxide
Rabeprazole
Esomeprazole sodium
Lansoprazole
Sucralfate
Magnesium hydroxide