Famotidine is used to treat a variety of conditions related to the stomach and intestines. It is commonly prescribed to treat stomach ulcers (gastric and duodenal), erosive esophagitis (heartburn or acid indigestion), and gastroesophageal reflux disease (GERD). Additionally, it can be used to prevent intestinal ulcers from recurring and to treat conditions where the stomach produces too much acid, such as Zollinger-Ellison syndrome