Some diarrhea medications can cause changes in stool color, such as black or white stool. However, passing white stools can indicate a serious medical condition, such as a blocked bile duct or liver ...

Large doses of antidiarrheal drugs like bismuth subsalicylate (Pepto-Bismol, Kaopectate) can cause very light stools that usually turn brown again after stopping. White or clay-colored stool can ...