Cetirizine hydrochloride
Cetirizine hydrochloride
Cetirizine hydrochloride>
(seh- TIH-rah-zeen)
Pregnancy Category: B Reactine Zyrtec (Rx)

Classification: Antihistamine

See Also: See also Antihistamines.

Action/Kinetics: A potent H ₁-receptor antagonist. A mild bronchodilator that protects against histmine-induced bronchospasm; negligible anticholinergic and sedative activity. Rapidly absorbed after PO administration; however, food delays the time to peak serum levels but does not decrease the total amount of drug absorbed. Poorly penetrates the CNS, but high levels are distributed to the skin. t 1/2: 8.3 hr (longer in elderly clients and in those with impaired liver or renal function). Excreted mostly unchanged (95%) in the urine; 10% is excreted in the feces.

Uses: Relief of symptoms associated with seasonal allergic rhinitis due to ragweed, grass, and tree pollens; perennial allergic rhinitis due to allergens such as dust mites, animal dander, and molds. Chronic idiopathic urticaria.

Contraindications: Lactation. In those hypersensitive to hydroxyzine.

Special Concerns: Due to the possibility of sedation, use with caution in situations requiring mental alertness. Safety and efficacy have not been determined in children less than 12 years of age.

Side Effects: See Antihistamines. The most common side effects are somnolence, dry mouth, fatigue, pharyngitis, and dizziness.

Overdose Management: Symptoms: Somnolence. Treatment: Symptomatic and supportive. Dialysis is not effective in removing the drug from the body.

How Supplied: Syrup: 1 mg/mL; Tablets: 5 mg, 10 mg.

Dosage
?Tablets Seasonal or perennial allergic rhinitis, chronic urticaria.
A dults and children over 6 years of age, initial: Depending on the severity of the symptoms, 5 or 10 mg (most common initial dose) once daily. In clients with decreased renal function (C _CR: 11-31 mL/min), in hemodialysis clients (C _CR less than 7 mL/min), and in those with impaired hepatic function, the dose is 5 mg once daily. Children, 2 to 5 years, initial: 2.5 mg once daily.