1. Dosage

Histamine H2-receptor antagonists (H2RAs) are FDA-approved for use in gastric ulcer, duodenal ulcer, gastroesophageal reflux disease (GERD), esophagitis, hypersecretory conditions, and non-ulcer indigestion/heartburn.

In April 2020, the Food and Drug Administration requested that manufacturers remove all prescription and over-the-counter (OTC) formulations of ranitidine from the market. The request for removal was precipitated by the discovery of N-nitrosodimethylamine (NDMA), a probable human carcinogen, in various ranitidine products. Zantac® is one of several trade names for ranitidine, and in June 2021, Sanofi Pharmaceuticals released Zantac 360°® as an OTC product. However, this new formulation contains famotidine rather than ranitidine.