2798 T3D2756 Cetirizine Cetirizine is a medication used for the treatment of allergies, hay fever, angioedema, and hives. It is a second-generation H1-receptor antagonist antihistamine and works by blocking H1 histamine receptors. It is a major metabolite of hydroxyzine, and has the same basic side effects, including dry mouth. 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. Cetirizine hydrochloride is a medication used for the treatment of allergies, hay fever, angioedema, and hives. It is a second-generation H1-receptor antagonist antihistamine and works by blocking H1 histamine receptors. It is a major metabolite of hydroxyzine, and has the same basic side effects, including dry mouth. 83881-51-0 2678 C21H25ClN2O3 388.155370 White powder. 112.5°C 101 mg/L Oral; mean peak plasma concentration (Cmax) of 114 ng/mL at a time (Tmax) of 2.2 hours postdose was observed for cetirizine. Cetirizine competes with histamine for binding at H<sub>1</sub>-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. Half Life: 8.3 hours No indication of carcinogenicity to humans (not listed by IARC). 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 Overdosage has been reported with ZYRTEC (cetirizine) . In one adult patient who took 150 mg of ZYRTEC (cetirizine) , the patient was somnolent but did not display any other clinical signs or abnormal blood chemistry or hematology results. In an 18 month old pediatric patient who took an overdose of ZYRTEC (cetirizine) (approximately 180 mg), restlessness and irritability were observed initially; this was followed by drowsiness. (L1712) Somnolence (sleepiness or unusual drowsiness), restlessness, irritability. Should overdose occur, treatment should be symptomatic or supportive, taking into account any concomitantly ingested medications. There is no known specific antidote to Cetirizine. (L1712) 2009-07-21T20:26:38Z 2014-12-24T20:25:51Z Cetirizine C07778 3561 Cetirizine DB00341 true OC(=O)COCCN1CCN(CC1)C(C1=CC=CC=C1)C1=CC=C(Cl)C=C1 C21H25ClN2O3 InChI=1/C21H25ClN2O3/c22-19-8-6-18(7-9-19)21(17-4-2-1-3-5-17)24-12-10-23(11-13-24)14-15-27-16-20(25)26/h1-9,21H,10-16H2,(H,25,26) InChIKey=ZKLPARSLTMPFCP-UHFFFAOYNA-N 388.888 388.155370383 Exogenous Solid 2.8 HMDB05032 CHEMBL1000 2577 <p>Manne Reddy, &#8220;Polymorphic forms of dihydrochloride salts of cetirizine and processes for preparation thereof.&#8221; U.S. Patent US20040186112, issued September 23, 2004.</p>