What is the role of simethicone in simethicone-containing antacids?

• A. Antidiarrheal
• B. Preservative
• C. Antifoaming agent
• D. None of the above

Answer: (C)

Simethicone’s role in these antacids is to act as an antifoaming agent. It lowers the surface tension of gas bubbles in the stomach and intestines, causing small bubbles to combine into larger ones that can be passed away more easily—often by belching or flatulence. This mechanical action helps relieve gas and bloating that can accompany acid-related symptoms. It isn’t an antisecretory or antidiarrheal drug, and it isn’t a preservative either. Because it isn’t absorbed into the bloodstream, its effect is local to the gut, working directly on the gas bubbles without systemic effects.