Cetirizine
Antihistamine
Second-generation antihistamine for allergic rhinitis and urticaria.
Generic name: Cetirizine
Brand names: Zyrtec, Cetrine, Cezil
Dosage
Adults and children ≥12: 10 mg once daily. Children 6–11: 5 mg once or twice daily.
Side effects
Mild drowsiness in some users, dry mouth, fatigue, headache.
Contraindications
Severe renal impairment requires dose reduction; hypersensitivity to cetirizine or hydroxyzine.
Description
Cetirizine selectively blocks peripheral H1 receptors with minimal central nervous system penetration, giving fast relief from itching, sneezing, and runny nose with less sedation than older antihistamines.