Ranitidine hydrochloride is a non-imidazole blocker of those histamine receptors that mediate gastric secretion (h2 receptors). It is used to treat gastrointestinal ulcers. Ranitidine is a medication that decreases stomach acid production. It is commonly used in treatment of peptic ulcer disease, gastroesophageal reflux disease, and zollinger–ellison syndrome. There is also tentative evidence of benefit for hives. It can be taken by mouth, by injection into a muscle, or into a vein.