Active ingredient: Cetirizine - Brands, Medical Use, Clinical Data

Brands, Medical Use, Clinical Data

Drug Category

• Anti-allergic Agents
• Antihistamines

Dosage Forms

• Tablets

Brands / Synonyms

Alerlisin; Cetirizina [Spanish]; Cetirizinum [Latin]; Cetrizine Hcl; Cetryn; Formistin; Hitrizin Film Tablet; Reactine; Setir; Virlix; Ziptek; Zirtek; Zyrlex; Zyrtec; Zyrtec ; Zyrtec-D

Indications

For the relief of symptoms associated with seasonal allergic rhinitis, perennial allergic rhinitis and the treatment of the uncomplicated skin manifestations of chronic idiopathic urticaria

Pharmacology

Cetirizine, the active metabolite of the piperazine H₁-receptor antagonist hydroxyzine, is used to treat chronic idiopathic urticaria, perennial allergic rhinitis, seasonal allergic rhinitis, allergic asthma, physical urticaria, and atopic dermatitis.

Mechanism of Action

Cetirizine competes with histamine for binding at H₁-receptor sites on the effector cell surface, resulting in suppression of histaminic edema, flare, and pruritus. The low incidence of sedation can be attributed to reduced penetration of cetirizine into the CNS as a result of the less lipophilic carboxyl group on the ethylamine side chain.

Absorption

mean peak plasma concentration (Cmax) of 114 ng/mL at a time (Tmax) of 2.2 hours postdose was observed for cetirizine

Toxicity

Somnolence (sleepiness or unusual drowsiness), restlessness, irritability

Biotrnasformation / Drug Metabolism

Not Available

Contraindications

Cetirizine is contraindicated in those patients with a known hypersensitivity to it or any of its ingredients or hydroxyzine.

Drug Interactions

Pharmacokinetic interaction studies with cetirizine in adults were conducted with pseudoephedrine, antipyrine, ketoconazole, erythromycin and azithromycin. No interactions were observed. In a multiple dose study of theophylline (400 mg once daily for 3 days) and cetirizine (20 mg once daily for 3 days), a 16% decrease in the clearance of cetirizine was observed. The disposition of theophylline was not altered by concomitant cetirizine administration.

Drug-Drug Interactions: No clinically significant drug interactions have been found with theophylline at a low dose, azithromycin, pseudoephedrine, ketoconazole, or erythromycin. There was a small decrease in the clearance of cetirizine caused by a 400-mg dose of theophylline; it is possible that larger theophylline doses could have a greater effect.