Bismuth subsalicylate is an antacid and antidiarrheal active ingredient available in over-the-counter (OTC) medicines that treat heartburn, indigestion, upset stomach, nausea, diarrhea, and other gastrointestinal ailments.
Bismuth subsalicylate is approved by the U.S. Food and Drug Administration (FDA) and is safe and effective when used according to the Drug Facts label.
Children and teenagers who have or are recovering from chicken pox or flu-like symptoms should not use an OTC medicine containing bismuth subsalicylate. If nausea or vomiting occurs, contact a healthcare provider immediately. These symptoms could be an early sign of Reye’s syndrome, which is a rare but serious illness.