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Zyrtec® (cetirizine)

Organon and Co · FDA-approved active Small molecule

Zyrtec® (cetirizine) is a H1-receptor antagonist (second-generation antihistamine) Small molecule drug developed by Organon and Co. It is currently FDA-approved for Seasonal and perennial allergic rhinitis, Chronic urticaria (hives).

Cetirizine is a selective H1-receptor antagonist that blocks histamine binding to H1 receptors on cells, preventing allergic symptoms.

Cetirizine is a selective H1-receptor antagonist that blocks histamine binding to H1 receptors on cells, preventing allergic symptoms. Used for Seasonal and perennial allergic rhinitis, Chronic urticaria (hives).

At a glance

Generic nameZyrtec® (cetirizine)
SponsorOrganon and Co
Drug classH1-receptor antagonist (second-generation antihistamine)
TargetH1 receptor
ModalitySmall molecule
Therapeutic areaAllergy/Immunology
PhaseFDA-approved

Mechanism of action

Cetirizine competitively inhibits histamine at peripheral H1 receptors, reducing the release and effects of histamine that cause itching, sneezing, rhinorrhea, and urticaria. As a second-generation antihistamine, it is highly selective for H1 receptors and has minimal central nervous system penetration due to its hydrophilic nature and poor blood-brain barrier crossing, resulting in reduced sedation compared to first-generation antihistamines.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

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

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Frequently asked questions about Zyrtec® (cetirizine)

What is Zyrtec® (cetirizine)?

Zyrtec® (cetirizine) is a H1-receptor antagonist (second-generation antihistamine) drug developed by Organon and Co, indicated for Seasonal and perennial allergic rhinitis, Chronic urticaria (hives).

How does Zyrtec® (cetirizine) work?

Cetirizine is a selective H1-receptor antagonist that blocks histamine binding to H1 receptors on cells, preventing allergic symptoms.

What is Zyrtec® (cetirizine) used for?

Zyrtec® (cetirizine) is indicated for Seasonal and perennial allergic rhinitis, Chronic urticaria (hives).

Who makes Zyrtec® (cetirizine)?

Zyrtec® (cetirizine) is developed and marketed by Organon and Co (see full Organon and Co pipeline at /company/organon-and-co).

What drug class is Zyrtec® (cetirizine) in?

Zyrtec® (cetirizine) belongs to the H1-receptor antagonist (second-generation antihistamine) class. See all H1-receptor antagonist (second-generation antihistamine) drugs at /class/h1-receptor-antagonist-second-generation-antihistamine.

What development phase is Zyrtec® (cetirizine) in?

Zyrtec® (cetirizine) is FDA-approved (marketed).

What are the side effects of Zyrtec® (cetirizine)?

Common side effects of Zyrtec® (cetirizine) include Headache, Somnolence/drowsiness, Fatigue, Dry mouth, Pharyngitis.

What does Zyrtec® (cetirizine) target?

Zyrtec® (cetirizine) targets H1 receptor and is a H1-receptor antagonist (second-generation antihistamine).

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