Zantac belongs to a group of drugs called histamine-2 blockers. Zantac works by reducing the amount of acid your stomach produces.
Zantac is used to treat and prevent ulcers in the stomach and intestines. It also treats conditions in which the stomach produces too much acid, such as Zollinger-Ellison syndrome. Zantac also treats gastroesophageal reflux disease (GERD) and other conditions in which acid backs up from the stomach into the esophagus, causing heartburn.