Prevent & relieve heartburn with Maximum Strength PEPCID AC® tablets with famotidine. Our strongest acid control formula helps control stomach acid all day or all night. PEPCID® is a histamine-2 blocker (H2 blocker) with the active ingredient famotidine that helps relieve heartburn by reducing the amount of acid in the stomach. Famotidine is used to treat stomach ulcers (gastric and duodenal), erosive esophagitis (heartburn or acid indigestion), and gastroesophageal reflux disease (GERD). GERD is a condition where the acid in the stomach washes back up into the esophagus. Pepcid is a histamine-2 blocker that works by decreasing the amount of acid the stomach produces. Pepcid 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. Overview: Famotidine is used to treat heartburn, ulcers, and other conditions caused by too much stomach acid. It is available by prescription and over-the-counter (OTC). Famotidine is an H2. Famotidine, sold under the brand name Pepcid among others, is a histamine H 2 receptor antagonist medication that decreases stomach acid production. [4] It is used to treat peptic ulcer disease, gastroesophageal reflux disease, and Zollinger–Ellison syndrome. [4] Pepcid (famotidine): H2 blocker for heartburn/GERD and ulcers. OTC/Rx dosing, onset, interactions, side effects, and prices by country. Pepcid (Famotidine) may treat, side effects, dosage, drug interactions, warnings, patient labeling, reviews, and related medications including drug comparison and health resources. Famotidine is a histamine-2 blocker that works by decreasing the amount of acid the stomach produces. Famotidine 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. Famotidine (Pepcid and Zantac) treats conditions that cause too much stomach acid, like heartburn, stomach ulcers and reflux disease.