Ranitidine, a histamine H2-receptor antagonist (H2RA), was for decades a cornerstone in the management of gastric acid-related disorders. From its introduction in the early 1980s, it offered a significant advancement over earlier antacids, providing longer-lasting and more predictable suppression of gastric acid secretion. It became one of the most widely prescribed medications globally, available both by prescription and, later, as an over-the-counter (OTC) product for heartburn and acid indigestion. Its story, however, took a dramatic turn in 2019-2020, making a thorough understanding of its pharmacology, uses, and the reasons for its market withdrawal essential for clinical practice and patient safety.
