Cetirizine
PronunciationPronunciation: se-TIR-i-zeen
Class: Piperazine, peripherally selective
Trade Names
All Day Children's Allergy
- Tablets, chewable 10 mg
Zyrtec
- Tablets 5 mg
- Tablets 10 mg
- Tablets, chewable 5 mg
- Tablets, chewable 10 mg
- Syrup 5 mg per 5 mL
Reactine (Canada)
Pharmacology
Competitively antagonizes histamine at the H 1 -receptor site.
Pharmacokinetics
Absorption
Rapidly absorbed. T max is approximately 1 h. C max is 311 ng/mL.
FoodT max is delayed 1.7 h, and C max is decreased 23%.
Distribution
93% protein bound.
Metabolism
Cetirizine has a low degree of first-pass metabolism. It also is metabolized by oxidative O-dealkylation to an inactive metabolite.
Elimination
70% is excreted in the urine (50% as unchanged drug) and 10% in the feces. The elimination half-life is 8.3 h. Cl is approximately 53 mL/min.
Onset
20 to 60 min.
Duration
At least 24 h.
Special Populations
Renal Function ImpairmentModerate impairment (CrCl 11 to 31 mL/min)
The half-life is increased 3-fold, and Cl is decreased 70%. Dosage adjustment is recommended in those with moderate or severe impairment.
Hepatic Function ImpairmentThe half-life is increased 50%, and Cl is decreased 40%. Dosage adjustment is recommended.
ElderlyThe half-life is prolonged 50%, and Cl is 40% lower. Dosage adjustment is recommended.
ChildrenCl is increased, and half-life is decreased.
Indications and Usage
Symptomatic relief of symptoms (eg, nasal, nonnasal) associated with seasonal and perennial allergic rhinitis; treatment of uncomplicated skin manifestations of chronic idiopathic urticaria.
Unlabeled Uses
Bronchial asthma.
Contraindications
Hypersensitivity to any components of the product or to hydroxyzine.
Dosage and Administration
Adults and Children 6 y of age and olderPO 5 or 10 mg/day (max, 10 mg/day).
Children 2 to 5 y of agePO 2.5 mg once daily (max, 5 mg/day as 5 mg once daily or 2.5 mg every 12 h).
Children 6 mo to younger than 2 y of agePO 2.5 mg once daily. The dose in 12 to 23 mo of age may be increased to a max dosage of 5 mg once daily or 2.5 mg every 12 h.
Elderly (77 years of age and older)PO 5 mg/day.
Hepatic ImpairmentPO 5 mg/day. Do not administer to children younger than 6 y of age with hepatic impairment.
Renal ImpairmentCrCl 11 to 31 mL/min or hemodialysis
PO 5 mg/day. Do not administer to children younger than 6 y of age with renal impairment.
General Advice
- Administer prescribed dose without regard to meals. Administer with food if GI upset occurs.
- Administer chewable tablets with or without water.
- Measure and administer prescribed dose of syrup using dosing spoon, syringe, or cup.
- Syrup is recommended for children younger than 2 y of age.
Storage/Stability
Store between 68° and 77°F. Syrup also can be stored in refrigerator.
Drug Interactions
Alcohol, sedatives, tranquilizersAsk a health care provider before using concurrently with cetirizine. Concomitant use may increase drowsiness. Avoid alcohol.
Laboratory Test Interactions
May prevent or diminish otherwise positive reactions to skin tests.
Adverse Reactions
Cardiovascular
Cardiac failure, hypertension, palpitation, syncope, tachycardia (less than 2%); severe hypotension (postmarketing).
CNS
Headache, somnolence (14%); fatigue (6%); dizziness (2%); aggressive reactions, convulsions, drowsiness, hallucinations, orofacial dyskinesia, suicidal ideation (postmarketing).
EENT
Pharyngitis (6%); epistaxis (4%).
GI
Abdominal pain (6%); dry mouth (5%); diarrhea, nausea, vomiting (3%).
Genitourinary
Glomerulonephritis (postmarketing).
Hematologic-Lymphatic
Hemolytic anemia, thrombocytopenia (postmarketing).
Hepatic
Cholestasis, hepatitis (postmarketing).
Hypersensitivity
Anaphylaxis (postmarketing).
Respiratory
Coughing (4%); bronchospasm (3%).
Miscellaneous
Stillbirth, suicide (postmarketing).
Precautions
MonitorAllergy symptomsAssess patient for allergy symptoms (eg, hives, itching, nasal congestion, rhinitis, sneezing, watery eyes) before starting therapy, and periodically throughout therapy. |
Pregnancy
Category B .
Lactation
Excreted in breast milk.
Children
Safety and efficacy not established in children younger than 6 mo of age. Ask a health care provider before using the OTC products in children younger than 6 y of age.
Elderly
Ask a health care provider before using the OTC product in adults 65 y of age and older. Dosage adjustment may be needed.
Renal Function
Dosage adjustment may be needed.
Hepatic Function
Dosage adjustment may be needed.
Overdosage
Symptoms
Drowsiness, irritability, restlessness, somnolence.
Patient Information
- Advise patient to take each dose without regard to meals but to take with food if stomach upset occurs.
- Advise patient or caregiver using syrup to measure and administer each dose using a dosing spoon, syringe, or cup.
- Advise patient using chewable tablet that tablet may be taken with or without water.
- Advise patient that if allergy symptoms are not controlled not to increase the dose of medication or frequency of use but to inform health care provider. Inform patient that larger doses or more frequent dosing does not increase effectiveness and may cause excessive drowsiness or other adverse reactions.
- Caution patient not to take any OTC antihistamines while taking this medication unless advised by health care provider.
- Caution patient to avoid alcohol and other CNS depressants (eg, sedatives) while using this medication.
- Caution patient that drug may cause drowsiness and to use caution while driving or performing other tasks requiring mental alertness until tolerance is determined.
- Advise patient that medication may cause sensitivity to sunlight and to avoid unnecessary exposure to UV light (sunlight, tanning booths), and to use sunscreen and wear protective clothing until tolerance is determined.
- Advise patient to take frequent sips of water, suck on ice chips or sugarless hard candy, or chew sugarless gum if dry mouth occurs.
- Advise patient having allergy skin testing not to take cetirizine for at least 4 days before the skin testing.
Copyright © 2009 Wolters Kluwer Health.
More Cetirizine resources
- Cetirizine Prescribing Information (FDA)
- cetirizine MedFacts Consumer Leaflet (Wolters Kluwer)
- Cetirizine Hydrochloride Monograph (AHFS DI)
- Zyrtec Prescribing Information (FDA)
- Zyrtec Consumer Overview




