II. Indications
- Pruritus
-
Allergic Rhinitis
- More rapid onset than other Non-Sedating Antihistamines (1 hour instead of 3 hours)
- Allows as needed dosing (such as for acute reactions, as allergists frequently used)
III. Mechanism
- Second Generation Antihistamine
- Cetirizine and Levocetirizine are analogs of the Sedating AntihistamineHydroxyzine
- Most sedating of the Non-Sedating Antihistamines (Second Generation Antihistamines)
IV. Medications
- Cetirizine (Zyrtec)
- Available OTC in U.S. since 2007
- Tablets or chewables: 5-10 mg
- Syrup 5 mg/5 ml
- Levocetirizine (Xyzal)
- Active isomer of Cetirizine (Zyrtec), hence dosing is 50% of Cetirizine
V. Dosing: Cetirizine (Zyrtec)
-
General
- FDA approved for perennial allergies in age >=6 months (seasonal allergies in age >=2 years)
- Allergists frequently prescribe Cetirizine in Allergic Reactions at higher dose and twice daily (off label use)
- Adult Dose (includes ages 6-11): 5 to 10 mg orally daily
- Child Dose (ages 2-5 years): 2.5 mg orally daily to twice daily
- Infant Dose (ages 6 months to 2 years): 2.5 mg orally daily
- Decrease dose in renal or hepatic Impairment
VI. Dosing: Levocetirizine (Xyzal)
- FDA approved for age >=6 months
- Adult Dose (ages 12 and over): 5 mg orally daily
- Child Dose (ages 6-11 years): 2.5 mg orally daily
VII. Safety
- Contraindicated in Lactation (Cetirizine and Levocetirizine)
- Pregnancy Class B agents (Cetirizine and Levocetirizine)
VIII. Adverse Effects
- See Antihistamine
- Drowsiness
- Although labeled as non-sedating, these Antihistamines may still cause sedation (esp. Cetirizine)
- May be sedating even at normally recommended doses (Hydroxyzine analog); reported by 10% of patients
IX. Resources
- Cetirizine Tablet (DailyMed)
- Levocetirizine (DailyMed)
X. References
- Howarth (1999) J Allergy Clin Immunol 104:927 [PubMed]
- Walsh (2001) Drugs 61:207 [PubMed]
- (2001) Med Lett Drugs Ther 43(1103):35
Images: Related links to external sites (from Bing)
Related Studies
| cetirizine (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| CETIRIZINE HCL 1 MG/ML SOLN | Generic | $0.02 per ml |
| CETIRIZINE HCL 1 MG/ML SYRUP | Generic | $0.02 per ml |
| CETIRIZINE HCL 10 MG CHEW TAB | Generic OTC | $1.79 each |
| CETIRIZINE HCL 10 MG TABLET | Generic OTC | $0.07 each |
| CETIRIZINE HCL 5 MG CHEW TAB | Generic OTC | $1.93 each |
| CETIRIZINE HCL 5 MG TABLET | Generic OTC | $0.05 each |
| CETIRIZINE-PSE ER 5-120 MG TAB | Generic OTC | $0.62 each |
| levocetirizine (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| LEVOCETIRIZINE 2.5 MG/5 ML SOL | Generic | $0.17 per ml |
| LEVOCETIRIZINE 5 MG TABLET | Generic | $0.07 each |
Ontology: Cetirizine (C0055147)
| Definition (NCI) | Cetirizine is a metabolite of hydroxyzine and a selective peripheral histamine H1-receptor antagonist. It is used for symptomatic treatment of seasonal and perennial allergic rhinitis and for chronic urticaria. (NCI) |
| Definition (MSH) | A potent second-generation histamine H1 antagonist that is effective in the treatment of allergic rhinitis, chronic urticaria, and pollen-induced asthma. Unlike many traditional antihistamines, it does not cause drowsiness or anticholinergic side effects. |
| Concepts | Pharmacologic Substance (T121) , Organic Chemical (T109) |
| MSH | D017332 |
| SnomedCT | 108655000, 372523007 |
| English | Cetirizine, (2-(4-((4-Chlorophenyl)phenylmethyl)-1-piperazinyl)ethoxy)acetic Acid, Acetic acid, (2-(4-((4-chlorophenyl)phenylmethyl)-1-piperazinyl)ethoxy)-, cetirizine, Cetirizine [Chemical/Ingredient], CETIRIZINE, Cetirizine (product), Cetirizine (substance) |
| Swedish | Cetirizin |
| Czech | cetirizin |
| Finnish | Setiritsiini |
| Russian | TSETIRIZIN, ЦЕТИРИЗИН |
| Japanese | セチリジン, セテリジン |
| Polish | Cetyryzyna |
| Spanish | cetiricina, cetirizina (producto), cetirizina (sustancia), cetirizina, Cetirizina |
| French | Cétirizine |
| German | Cetirizin |
| Italian | Cetirizina |
| Portuguese | Cetirizina |
Ontology: Zyrtec (C0162723)
| Definition (CHV) | brand name of an allergy medicine |
| Definition (CHV) | brand name of an allergy medicine |
| Definition (CHV) | brand name of an allergy medicine |
| Concepts | Pharmacologic Substance (T121) , Organic Chemical (T109) |
| MSH | D017332 |
| English | Zirtek, zyrtec [brand name], zirtek, zyrtec, ZyrTEC, Zyrtec, Pfizer Brand of Cetirizine Dihydrochloride, Pfizer Consumer Healthcare Brand of Cetirizine Dihydrochloride, Reactine, UCB Brand of Cetirizine Dihydrochloride, UCB Pharma Brand of Cetirizine Dihydrochloride, United Drug Brand of Cetirizine Dihydrochloride, Voltric |
Ontology: levocetirizine (C1174893)
| Definition (NCI) | A third generation, non-sedating, selective histamine H1 receptor antagonist, with antihistamine, anti-inflammatory and potential anti-angiogenic activities. Levocetirizine competes with endogenous histamine for binding at peripheral H1-receptor sites on the effector cell surface. This prevents the negative symptoms associated with histamine release and an allergic reaction. In addition, as histamine plays an important role in angiogenesis during an allergic inflammatory reaction, blocking the action of histamine may modulate the expression of proangiogenic factors and thus may prevent angiogenesis. As a third-generation histamine H1 receptor antagonist, levocetirizine has fewer side effects than most second-generation antihistamines. |
| Concepts | Organic Chemical (T109) , Pharmacologic Substance (T121) |
| MSH | C472067 |
| SnomedCT | 421889003, 391595003 |
| English | Levocetirizine (substance), levocetirizine [Chemical/Ingredient], levocetrizine, LEVOCETIRIZINE, (2-(4-((R)-p-chloro-alpha-phenylbenzyl)-1-piperazinyl)ethoxy)acetic acid, levocetirizine, Levocetirizine (product), Levocetirizine |
| Spanish | levocetirizina (sustancia), levocetirizina (producto), levocetirizina |
Ontology: Xyzal (C1311681)
| Concepts | Organic Chemical (T109) , Pharmacologic Substance (T121) |
| MSH | C472067 |
| English | xyzal, UCB brand of levocetirizine dihydrochloride, Xyzal, Xusal |
