Imodium Liquid Antidiarrheal Medicine contains loperamide hydrochloride, an antidiarrheal medicine used to help control the symptoms of acute, active, and traveler’s diarrhea. Its liquid formulation has a mint flavor and comes in a 4 fl oz bottle. Loperamide works by slowing intestinal movement, which helps reduce the frequency of bowel movements and allows more water to be absorbed from the intestines.