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H1 Receptor Antagonist

Merck Sharp & Dohme LLC · Phase 3 active Small molecule

H1 receptor antagonists block histamine binding to H1 receptors, reducing histamine-mediated allergic and inflammatory responses.

H1 receptor antagonists block histamine binding to H1 receptors, reducing histamine-mediated allergic and inflammatory responses. Used for Allergic rhinitis, Urticaria, Allergic reactions.

At a glance

Generic nameH1 Receptor Antagonist
SponsorMerck Sharp & Dohme LLC
Drug classH1 receptor antagonist
TargetH1 receptor
ModalitySmall molecule
Therapeutic areaAllergy/Immunology
PhasePhase 3

Mechanism of action

H1 receptor antagonists competitively inhibit histamine at H1 receptors located on smooth muscle, endothelial cells, and immune cells. This blocks histamine-induced effects such as vasodilation, increased vascular permeability, smooth muscle contraction, and itching. They are commonly used to treat allergic reactions, urticaria, and allergic rhinitis.

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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