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Cetirizine drops
Cetirizine is a selective H1-receptor antagonist that blocks histamine binding to H1 receptors on mast cells and basophils, preventing allergic cascade activation.
Cetirizine is a selective H1-receptor antagonist that blocks histamine binding to H1 receptors on mast cells and basophils, preventing allergic cascade activation. Used for Allergic rhinitis (seasonal and perennial), Chronic urticaria, Allergic conjunctivitis.
At a glance
| Generic name | Cetirizine drops |
|---|---|
| Also known as | Zyrtec, Simulant of Diphenhydramine Hydrochloride Injection |
| Sponsor | UCB Pharma |
| Drug class | H1-receptor antagonist (second-generation antihistamine) |
| Target | H1 receptor |
| Modality | Small molecule |
| Therapeutic area | Immunology / Allergy |
| Phase | FDA-approved |
Mechanism of action
Cetirizine competitively inhibits histamine at the H1 receptor, reducing the release and effects of inflammatory mediators responsible for allergic symptoms. As a second-generation antihistamine, it is highly selective for H1 receptors and does not significantly cross the blood-brain barrier, resulting in minimal sedation compared to first-generation antihistamines.
Approved indications
- Allergic rhinitis (seasonal and perennial)
- Chronic urticaria
- Allergic conjunctivitis
- Allergic asthma (adjunctive)
Common side effects
- Headache
- Somnolence
- Fatigue
- Dry mouth
- Pharyngitis
Key clinical trials
- A Study to Compare the Efficacy of Levocetirizine to Placebo in Reducing Symptoms of Seasonal Allergic Rhinitis (SAR) in Sensitive Subjects Exposed to Ragweed Pollen (PHASE2)
- A Multi-Center, Evaluation of the Onset and Duration of Action of AC-170 0.24% Compared to Vehicle (PHASE3)
- A Multi-Center Study Evaluating the Onset and Duration of Action of AC-170 0.24% Compared to Vehicle in the Conjunctival Allergen Challenge (CAC) (PHASE3)
- A Single-Center,Evaluation of the Onset and Duration of Action of AC-170 0.24% Compared to Vehicle (PHASE3)
- A Single-Center, Open-Label, Study of the Plasma Pharmacokinetics and Safety of AC-170 0.24% (PHASE1)
- Efficacy of AC-150 for the Treatment of Allergic Conjunctivitis in the Enviro-CAC™ Model (PHASE2)
- A Comparison of the Safety and Comfort of AC-170 (PHASE1)
- A Multi-Center, Vehicle-Controlled, Parallel-Group Study Evaluating the Safety of AC-170 Ophthalmic Solution (PHASE3)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Cetirizine drops CI brief — competitive landscape report
- Cetirizine drops updates RSS · CI watch RSS
- UCB Pharma portfolio CI