Medicines that reduce the amount of acid the stomach produces. They block histamine2 (HIH-stuh-min-too). Histamine signals the stomach to make acid. Prescription H2-blockers are Tagamet (cimetidine), Pepcid (famotidine), Axid (nizatidine), and Zantac (ranitidine). They are used to treat ulcer symptoms. Nonprescription H2-blockers are Zantac 75, Axid AR, Pepcid-AC, and Tagamet-HB. They are for GERD, heartburn, and acid indigestion.

