Last reviewed · How we verify

Drug: cimetidine

University of Maryland, Baltimore · FDA-approved active Small molecule

Cimetidine blocks histamine H2 receptors on gastric parietal cells to reduce stomach acid production.

Cimetidine blocks histamine H2 receptors on gastric parietal cells to reduce stomach acid production. Used for Duodenal ulcer, Gastric ulcer, Gastroesophageal reflux disease (GERD).

At a glance

Generic nameDrug: cimetidine
Also known asTagamet
SponsorUniversity of Maryland, Baltimore
Drug classH2 receptor antagonist
TargetHistamine H2 receptor
ModalitySmall molecule
Therapeutic areaGastroenterology
PhaseFDA-approved

Mechanism of action

Cimetidine is a competitive antagonist of histamine H2 receptors, which are responsible for stimulating gastric acid secretion. By blocking these receptors, it decreases both basal and stimulated acid production in the stomach. This mechanism makes it effective for treating acid-related gastrointestinal disorders.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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