ranitidine

drug

Also known as: Zantac

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Last updated

July 13, 2026

Quick Summary

Ranitidine, also known by the brand name Zantac, is a medication that functions as an H2 receptor antagonist. It works by blocking histamine's effect on the stomach, thereby reducing the secretion of gastric acid. This made it useful for treating conditions like gastroesophageal reflux and peptic ulcers.12

However, ranitidine was removed from the market in April 2021 due to safety concerns. The U.S. Food and Drug Administration (FDA) found that the drug could contain N-Nitrosodimethylamine (NDMA) in amounts exceeding appropriate levels. NDMA is classified as a probable human carcinogen, meaning it could potentially cause cancer. The FDA's decision to remove drugs from the market is based on whether their risks outweigh their benefits.3

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H2 receptor antagonist
…which include cimetidine (Tagamet) and ranitidine (Zantac), are used for short-term treatment of gastroesophageal reflux and, in combination with antibiotics, for peptic ulcer.
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…which include cimetidine (Tagamet) and ranitidine (Zantac), are used for short-term treatment of gastroesophageal reflux and, in combination with antibiotics, for peptic ulcer.
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digestive system disease
Ulcerative diseases
Histamine-receptor antagonists, such as cimetidine, ranitidine, and famotidine, block the action of histamine on the acid-secreting parietal cells of the stomach. Proton pump inhibitors, such as omeprazole, lansoprazole, and rabeprozale, inhibit the ATPase enzyme inside the parietal cell and prevent acid secretion. Most peptic ulcers not caused by H. pylori…
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Histamine-receptor antagonists, such as cimetidine, ranitidine, and famotidine, block the action of histamine on the acid-secreting parietal cells of the stomach. Proton pump inhibitors, such as omeprazole, lansoprazole, and rabeprozale, inhibit the ATPase enzyme inside the parietal cell and prevent acid secretion. Most peptic ulcers not caused by H. pylori…
Read More