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Claritin®
Claritin blocks histamine H1 receptors on cells, preventing histamine-mediated allergic responses.
Claritin blocks histamine H1 receptors on cells, preventing histamine-mediated allergic responses. Used for Allergic rhinitis (seasonal and perennial), Chronic idiopathic urticaria.
At a glance
| Generic name | Claritin® |
|---|---|
| Sponsor | Sanofi |
| Drug class | Second-generation H1-receptor antagonist (non-sedating antihistamine) |
| Target | Histamine H1 receptor |
| Modality | Small molecule |
| Therapeutic area | Immunology / Allergy |
| Phase | FDA-approved |
Mechanism of action
Loratadine, the active ingredient in Claritin, is a selective H1-receptor antagonist that crosses the blood-brain barrier minimally, reducing central nervous system effects. By competitively blocking histamine binding to H1 receptors on mast cells, endothelial cells, and smooth muscle, it prevents the cascade of allergic symptoms including itching, sneezing, rhinorrhea, and urticaria.
Approved indications
- Allergic rhinitis (seasonal and perennial)
- Chronic idiopathic urticaria
Common side effects
- Headache
- Somnolence
- Fatigue
- Dry mouth
- Nervousness
Key clinical trials
- Over-the-Counter Antihistamines & Heat Stress (PHASE4)
- Effects of Inhibiting Early Inflammation in Kidney Transplant Patients (PHASE2)
- A Study Comparing the Efficacy of Pataday® Once Daily Relief Extra Strength to Claritin® Tablets 24-Hour in Subjects With Allergic Conjunctivitis (PHASE4)
- Safety and Efficacy of Mometasone Furoate Nasal Spray With the Addition of Loratadine Versus Placebo in Participants With Seasonal Allergic Rhinitis (C94-145) (PHASE3)
- A Manufacturing Transfer Study Comparing the Bioequivalence of a Single Oral Dose of Claritin-D 12-Hour Extended Release Tablet From 2 Different Manufacturers Under Fasted Conditions in Healthy Adult Subjects (PHASE1)
- A Manufacturing Transfer Study Comparing the Bioequivalence of a Single Oral Dose of Claritin-D 12-Hour Extended Release Tablet From 2 Different Manufactuers Under Fed Conditions in Healthy Adult Subjects (PHASE1)
- NOLAN: Naproxen or Loratadine and Neulasta (PHASE2)
- Randomized, Double Blind, Parallel Group, Placebo Controlled, Multi-Center Study of the Efficacy and Safety of Cetirizine HCl Syrup vs. Loratadine Syrup vs. Placebo in Treatment of Children With Seasonal Allergic Rhinitis (SAR) (PHASE4)
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:
- Claritin® CI brief — competitive landscape report
- Claritin® updates RSS · CI watch RSS
- Sanofi portfolio CI