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H2 Receptor Antagonist

Merck Sharp & Dohme LLC · Phase 3 active Small molecule

H2 receptor antagonists block histamine H2 receptors on gastric parietal cells to reduce stomach acid secretion.

H2 receptor antagonists block histamine H2 receptors on gastric parietal cells to reduce stomach acid secretion. Used for Peptic ulcer disease, Gastroesophageal reflux disease (GERD), Zollinger-Ellison syndrome.

At a glance

Generic nameH2 Receptor Antagonist
Also known asFamotidine, H2RA
SponsorMerck Sharp & Dohme LLC
Drug classH2 receptor antagonist
TargetHistamine H2 receptor
ModalitySmall molecule
Therapeutic areaGastroenterology
PhasePhase 3

Mechanism of action

These drugs competitively inhibit histamine binding to H2 receptors, which normally stimulate gastric acid production. By blocking this pathway, H2 antagonists decrease both basal and stimulated acid secretion, raising gastric pH and allowing ulcers and acid-related conditions to heal. They are used for peptic ulcer disease, gastroesophageal reflux disease (GERD), and other acid-related 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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