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Cetirizine

Cetirizine, sold under the brand name Zyrtec among others, is a second-generation antihistamine used to treat allergic rhinitis (hay fever), dermatitis, and urticaria (hives). It is taken by mouth. Effects generally begin within an hour and last for about a day. The degree of benefit is similar to other antihistamines such as diphenhydramine.

Cetirizine
Clinical data
Pronunciation
Trade namesZyrtec, Incidal, others
AHFS/Drugs.comMonograph
MedlinePlusa698026
License data
Pregnancy
category
  • AU: B2
Routes of
administration
By mouth
ATC code
Legal status
Legal status
Pharmacokinetic data
BioavailabilityWell-absorbed (>70%)
Protein binding88–96%
MetabolismMinimal (non-cytochrome P450-mediated)
Onset of action20–42 minutes
Eliminationhalf-lifeMean: 8.3 hours
Range: 6.5–10 hours
Duration of action≥24 hours
ExcretionUrine: 70–85%
Feces: 10–13%
Identifiers
  • (±)-[2-[4-[(4-Chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]acetic acid
CAS Number
PubChemCID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard(EPA)
ECHA InfoCard100.223.545
Chemical and physical data
FormulaC21H25ClN2O3
Molar mass388.89 g·mol−1
3D model (JSmol)
  • Clc1ccc(cc1)C(c2ccccc2)N3CCN(CC3)CCOCC(=O)O
  • InChI=1S/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) Y
  • Key:ZKLPARSLTMPFCP-UHFFFAOYSA-N Y
(verify)

Common side effects include sleepiness, dry mouth, headache, and abdominal pain. The degree of sleepiness that occurs is generally less than with first generation antihistamines. Serious side effects may include aggression and angioedema. Use in pregnancy appears safe, but use during breastfeeding is not recommended. The medication works by blocking histamine H1 receptors, mostly outside the brain.

It was patented in 1981 and came into medical use in 1987. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication. In 2019, it was the 67th most commonly prescribed medication in the United States, with more than 11million prescriptions.

Allergies

Cetirizine's primary indication is for hay fever and other allergies. Because the symptoms of itching and redness in these conditions are caused by histamine acting on the H1 receptor, blocking those receptors temporarily relieves those symptoms.

Cetirizine is also commonly prescribed to treat acute and (in particular cases) chronic urticaria, more efficiently than any other second-generation antihistamine.

Available forms

Cetirizine is available over-the-counter in the US in the form of 5 and 10 mg tablets. A 20 mg strength is available by prescription only. In the UK, up to 30 tablets of 10 mg are on the general sales list (of pharmaceuticals) and can be purchased without a prescription and without pharmacist supervision. The drug can be in the form of tablets, capsules or a syrup.

Commonly reported side effects of cetirizine include headache, dry mouth, drowsiness, and fatigue, while more serious but rare side effects include cardiac failure, tachycardia, and edema.

Discontinuing cetirizine after prolonged use (typically, use beyond six months) may result in generalized itching.

L-Stereoisomer, levocetirizine (top) and D-stereoisomer of cetirizine.

Pharmacodynamics

Cetirizine acts as a highly selective antagonist of the histamine H1 receptor. The Ki values for the H1 receptor are approximately 6 nM for cetirizine, 3 nM for levocetirizine, and 100 nM for dextrocetirizine, indicating that the levorotatory enantiomer is the main active form. Cetirizine has 600-fold or greater selectivity for the H1 receptor over a wide variety of other sites, including muscarinic acetylcholine, serotonin, dopamine, and α-adrenergic receptors, among many others. The drug shows 20,000-fold or greater selectivity for the H1 receptor over the five muscarinic acetylcholine receptors, and hence does not exhibit anticholinergic effects. It shows negligible inhibition of the hERG channel (IC50 > 30 μM) and no cardiotoxicity has been observed with cetirizine at doses of up to 60 mg/day, six times the normal recommended dose and the highest dose of cetirizine that has been studied in healthy subjects.

Cetirizine crosses the blood–brain barrier only slightly, and for this reason, it produces minimal sedation compared to many other antihistamines. A positron emission tomography (PET) study found that brain occupancy of the H1 receptor was 12.6% for 10 mg cetirizine, 25.2% for 20 mg cetirizine, and 67.6% for 30 mg hydroxyzine. (A 10 mg dose of cetirizine equals about a 30 mg dose of hydroxyzine in terms of peripheral antihistamine effect.) PET studies with antihistamines have found that brain H1 receptor occupancy of more than 50% is associated with a high prevalence of somnolence and cognitive decline, whereas brain H1 receptor occupancy of less than 20% is considered to be non-sedative. In accordance, H1 receptor occupancy correlated well with subjective sleepiness for 30 mg hydroxyzine but there was no correlation for 10 or 20 mg cetirizine. As such, brain penetration and brain H1 receptor occupancy by cetirizine are dose-dependent, and in accordance, while cetirizine at doses of 5 to 10 mg have been reported to be non-sedating or mildly sedating, a higher dose of 20 mg has been found to induce significant drowsiness in other studies.

Cetirizine also shows anti-inflammatory properties independent of H1 receptors. The effect is exhibited through suppression of the NF-κB pathway, and by regulating the release of cytokines and chemokines, thereby regulating the recruitment of inflammatory cells. It has been shown to inhibit eosinophil chemotaxis and LTB4 release. At a dosage of 20 mg, Boone et al. found that it inhibited the expression of VCAM-1 in patients with atopic dermatitis.

Pharmacokinetics

Absorption

Cetirizine is rapidly and extensively absorbed upon oral administration in tablet or syrup form. The oral bioavailability of cetirizine is at least 70% and of levocetirizine is at least 85%. The Tmax of cetirizine is approximately 1.0 hour regardless of formulation. The pharmacokinetics of cetirizine have been found to increase linearly with dose across a range of 5 to 60 mg. Its Cmax following a single dose has been found to be 257 ng/mL for 10 mg and 580 ng/mL for 20 mg. Food has no effect on the bioavailability of cetirizine but has been found to delay the Tmax by 1.7 hours (i.e., to approximately 2.7 hours) and to decrease the Cmax by 23%. Similar findings were reported for levocetirizine, which had its Tmax delayed by 1.25 hours and its Cmax decreased by about 36% when administered with a high-fat meal. Steady-state levels of cetirizine occur within 3 days and there is no accumulation of the drug with chronic administration. Following once-daily administration of 10 mg cetirizine for 10 days, the mean Cmax was 311 ng/mL.

Distribution

The mean plasma protein binding of cetirizine has been found to be 93 to 96% across a range of 25 to 1,000 ng/mL independent of concentration. Plasma protein binding of 88 to 96% has also been reported across multiple studies. The drug is bound to albumin with high affinity, while α1-acid glycoprotein and lipoproteins contribute much less to total plasma protein binding. The unbound or free fraction of levocetirizine has been reported to be 8%. The true volume of distribution of cetirizine is unknown but is estimated to be 0.3 to 0.45 L/kg. Cetirizine poorly and slowly crosses the blood–brain barrier, which is due mainly to its chemical properties but also to a minor extent to its activity as a P-glycoprotein substrate.

Metabolism

Cetirizine does not undergo extensive metabolism. It is notably not metabolized by the cytochrome P450 system. Because of this, it does not interact significantly with drugs that inhibit or induce cytochrome P450 enzymes such as theophylline, erythromycin, clarithromycin, cimetidine, or alcohol. While cetirizine does not undergo extensive metabolism or metabolism by the cytochrome P450 enzyme, it does undergo some metabolism by other means, the metabolic pathways of which include oxidation and conjugation. Plasma radioactivity attributed to unchanged cetirizine is more than 90% at 2 hours, 80% at 10 hours, and 70% at 24 hours, indicating limited and slow metabolism. The enzymes responsible for transformation of cetirizine have not been identified.

Elimination

Cetirizine is eliminated approximately 70 to 85% in the urine and 10 to 13% in the feces. About 50 or 60% of cetirizine eliminated in the urine is unchanged. It is eliminated in the urine via an active transport mechanism. The elimination half-life of cetirizine ranges from 6.5 to 10 hours in healthy adults, with a mean across studies of approximately 8.3 hours. Its duration of action is at least 24 hours. The elimination half-life of cetirizine is increased in the elderly (to 12 hours), in hepatic impairment (to 14 hours), and in renal impairment (to 20 hours).

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Cetirizine contains L- and D-stereoisomers. Chemically, levocetirizine is the active L-enantiomer of cetirizine. The drug is a member of the diphenylmethylpiperazine group of antihistamines. Analogues include cyclizine and hydroxyzine.

Synthesis

Cetirizine synthesis:

The 1-(4-chlorophenylmethyl)-piperazine is alkylated with methyl (2-chloroethoxy)-acetate in the presence of sodium carbonate and xylene solvent to produce the Sn2 substitution product in 28% yield. Saponification of the acetate ester is done by refluxing with potassium hydroxide in absolute ethanol to afford a 56% yield of the potassium salt intermediate. This is then hydrolyzed with aqueous HCl and extracted to give an 81% yield of the carboxylic acid product.

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A package of 10 mg cetirizine tablets.
Zyrtec-D, a combination of cetirizine and pseudoephedrine.

Formerly prescription-only in many countries, cetirizine is now available without prescription in most countries. In some countries it is available over-the-counter only in packages containing seven or ten 10 mg doses.

Like many other antihistamine medications, cetirizine is commonly prescribed in combination with pseudoephedrine, a decongestant.[medical citation needed] These combinations are often marketed using the same brand name as the cetirizine with a "-D" suffix (Zyrtec-D, Virlix-D, etc.)

Cetirizine is marketed under the brand names Alatrol, Alerid, Alzene, Cerchio, Cetirin, Cetriz, Cetzine, Cezin, Cetgel, Cirrus, Histec, Histazine, Humex, Letizen, Okacet (Cipla), Reactine, Razene, Rigix, Sensahist (Oethmann, South Africa), Triz, Zetop, Zirtec, Zirtek, Zodac, Zyllergy, Zynor, Zyrlek, and Zyrtec (Johnson & Johnson), among others.

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Cetirizine
Cetirizine Language Watch Edit 160 160 Redirected from Zyrtec Cetirizine sold under the brand name Zyrtec among others is a second generation antihistamine used to treat allergic rhinitis hay fever dermatitis and urticaria hives 5 It is taken by mouth 6 Effects generally begin within an hour and last for about a day 6 The degree of benefit is similar to other antihistamines such as diphenhydramine 6 CetirizineClinical dataPronunciation s ɛ ˈ t ɪr ɪ z iː n Trade namesZyrtec Incidal othersAHFS Drugs comMonographMedlinePlusa698026License dataUS DailyMed Cetirizine US FDA CetirizinePregnancy categoryAU B2Routes of administrationBy mouthATC codeR06AE07 WHO Legal statusLegal statusAU Unscheduled CA OTC UK General sales list GSL OTC P US OTC Rx only In general Over the counter OTC Pharmacokinetic dataBioavailabilityWell absorbed gt 70 1 Protein binding88 96 1 MetabolismMinimal non cytochrome P450 mediated 3 2 Onset of action20 42 minutes 2 Elimination half lifeMean 8 3 hours 3 2 Range 6 5 10 hours 4 Duration of action 24 hours 4 ExcretionUrine 70 85 3 Feces 10 13 3 IdentifiersIUPAC name 2 4 4 Chlorophenyl phenylmethyl 1 piperazinyl ethoxy acetic acidCAS Number83881 51 0 YPubChem CID2678IUPHAR BPS1222DrugBankDB00341 YChemSpider2577 YUNIIYO7261ME24KEGGD07662 YChEBICHEBI 3561 YChEMBLChEMBL1000 YCompTox Dashboard EPA DTXSID4022787ECHA InfoCard100 223 545Chemical and physical dataFormulaC 21H 25Cl N 2O 3Molar mass388 89 g mol 13D model JSmol Interactive imageSMILES Clc1ccc cc1 C c2ccccc2 N3CCN CC3 CCOCC O OInChI InChI 1S 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 YKey ZKLPARSLTMPFCP UHFFFAOYSA N Y verify Common side effects include sleepiness dry mouth headache and abdominal pain 6 The degree of sleepiness that occurs is generally less than with first generation antihistamines 5 Serious side effects may include aggression and angioedema 5 Use in pregnancy appears safe but use during breastfeeding is not recommended 7 The medication works by blocking histamine H1 receptors mostly outside the brain 6 It was patented in 1981 8 and came into medical use in 1987 9 It is on the World Health Organization s List of Essential Medicines 10 It is available as a generic medication 5 In 2019 it was the 67th most commonly prescribed medication in the United States with more than 11 million prescriptions 11 12 Medical uses EditAllergies Edit Cetirizine s primary indication is for hay fever and other allergies Because the symptoms of itching and redness in these conditions are caused by histamine acting on the H1 receptor blocking those receptors temporarily relieves those symptoms 13 Cetirizine is also commonly prescribed to treat acute and in particular cases chronic urticaria more efficiently than any other second generation antihistamine 13 Available forms Edit Cetirizine is available over the counter in the US in the form of 5 and 10 mg tablets A 20 mg strength is available by prescription only 3 In the UK up to 30 tablets of 10 mg are on the general sales list of pharmaceuticals and can be purchased without a prescription and without pharmacist supervision 14 The drug can be in the form of tablets capsules or a syrup 14 Adverse effects EditCommonly reported side effects of cetirizine include headache dry mouth drowsiness and fatigue while more serious but rare side effects include cardiac failure tachycardia and edema 15 Discontinuing cetirizine after prolonged use typically use beyond six months may result in generalized itching 16 17 18 Pharmacology Edit L Stereoisomer levocetirizine top and D stereoisomer of cetirizine Pharmacodynamics Edit Cetirizine acts as a highly selective antagonist of the histamine H1 receptor 3 The Ki values for the H1 receptor are approximately 6 nM for cetirizine 3 nM for levocetirizine and 100 nM for dextrocetirizine indicating that the levorotatory enantiomer is the main active form 3 Cetirizine has 600 fold or greater selectivity for the H1 receptor over a wide variety of other sites including muscarinic acetylcholine serotonin dopamine and a adrenergic receptors among many others 3 The drug shows 20 000 fold or greater selectivity for the H1 receptor over the five muscarinic acetylcholine receptors and hence does not exhibit anticholinergic effects 19 20 It shows negligible inhibition of the hERG channel IC50 gt 30 mM 21 and no cardiotoxicity has been observed with cetirizine at doses of up to 60 mg day six times the normal recommended dose 3 and the highest dose of cetirizine that has been studied in healthy subjects 22 Cetirizine crosses the blood brain barrier only slightly and for this reason it produces minimal sedation compared to many other antihistamines 23 A positron emission tomography PET study found that brain occupancy of the H1 receptor was 12 6 for 10 mg cetirizine 25 2 for 20 mg cetirizine and 67 6 for 30 mg hydroxyzine 24 A 10 mg dose of cetirizine equals about a 30 mg dose of hydroxyzine in terms of peripheral antihistamine effect 25 PET studies with antihistamines have found that brain H1 receptor occupancy of more than 50 is associated with a high prevalence of somnolence and cognitive decline whereas brain H1 receptor occupancy of less than 20 is considered to be non sedative 26 In accordance H1 receptor occupancy correlated well with subjective sleepiness for 30 mg hydroxyzine but there was no correlation for 10 or 20 mg cetirizine 24 As such brain penetration and brain H1 receptor occupancy by cetirizine are dose dependent and in accordance while cetirizine at doses of 5 to 10 mg have been reported to be non sedating or mildly sedating a higher dose of 20 mg has been found to induce significant drowsiness in other studies 24 Cetirizine also shows anti inflammatory properties independent of H1 receptors 27 The effect is exhibited through suppression of the NF kB pathway and by regulating the release of cytokines and chemokines thereby regulating the recruitment of inflammatory cells 28 29 30 31 32 It has been shown to inhibit eosinophil chemotaxis and LTB4 release 33 At a dosage of 20 mg Boone et al found that it inhibited the expression of VCAM 1 in patients with atopic dermatitis 33 Pharmacokinetics Edit Absorption Edit Cetirizine is rapidly and extensively absorbed upon oral administration in tablet or syrup form 3 The oral bioavailability of cetirizine is at least 70 and of levocetirizine is at least 85 1 The Tmax of cetirizine is approximately 1 0 hour regardless of formulation 2 The pharmacokinetics of cetirizine have been found to increase linearly with dose across a range of 5 to 60 mg 3 Its Cmax following a single dose has been found to be 257 ng mL for 10 mg and 580 ng mL for 20 mg 2 Food has no effect on the bioavailability of cetirizine but has been found to delay the Tmax by 1 7 hours i e to approximately 2 7 hours and to decrease the Cmax by 23 3 2 34 Similar findings were reported for levocetirizine which had its Tmax delayed by 1 25 hours and its Cmax decreased by about 36 when administered with a high fat meal 34 Steady state levels of cetirizine occur within 3 days and there is no accumulation of the drug with chronic administration 2 Following once daily administration of 10 mg cetirizine for 10 days the mean Cmax was 311 ng mL 35 Distribution Edit The mean plasma protein binding of cetirizine has been found to be 93 to 96 across a range of 25 to 1 000 ng mL independent of concentration 2 Plasma protein binding of 88 to 96 has also been reported across multiple studies 1 The drug is bound to albumin with high affinity while a1 acid glycoprotein and lipoproteins contribute much less to total plasma protein binding 1 The unbound or free fraction of levocetirizine has been reported to be 8 1 The true volume of distribution of cetirizine is unknown but is estimated to be 0 3 to 0 45 L kg 3 1 Cetirizine poorly and slowly crosses the blood brain barrier which is due mainly to its chemical properties but also to a minor extent to its activity as a P glycoprotein substrate 1 Metabolism Edit Cetirizine does not undergo extensive metabolism 3 It is notably not metabolized by the cytochrome P450 system 36 Because of this it does not interact significantly with drugs that inhibit or induce cytochrome P450 enzymes such as theophylline erythromycin clarithromycin cimetidine or alcohol 3 While cetirizine does not undergo extensive metabolism or metabolism by the cytochrome P450 enzyme it does undergo some metabolism by other means the metabolic pathways of which include oxidation and conjugation 3 2 Plasma radioactivity attributed to unchanged cetirizine is more than 90 at 2 hours 80 at 10 hours and 70 at 24 hours indicating limited and slow metabolism 2 The enzymes responsible for transformation of cetirizine have not been identified 3 Elimination Edit Cetirizine is eliminated approximately 70 to 85 in the urine and 10 to 13 in the feces 3 About 50 or 60 of cetirizine eliminated in the urine is unchanged 3 2 It is eliminated in the urine via an active transport mechanism 2 The elimination half life of cetirizine ranges from 6 5 to 10 hours in healthy adults with a mean across studies of approximately 8 3 hours 3 2 Its duration of action is at least 24 hours 2 The elimination half life of cetirizine is increased in the elderly to 12 hours in hepatic impairment to 14 hours and in renal impairment to 20 hours 2 Chemistry EditThis section does not cite any sources Please help improve this section by adding citations to reliable sources Unsourced material may be challenged and removed July 2020 Learn how and when to remove this template message Cetirizine contains L and D stereoisomers Chemically levocetirizine is the active L enantiomer of cetirizine The drug is a member of the diphenylmethylpiperazine group of antihistamines Analogues include cyclizine and hydroxyzine Synthesis Edit Cetirizine synthesis 8 The 1 4 chlorophenylmethyl piperazine is alkylated with methyl 2 chloroethoxy acetate in the presence of sodium carbonate and xylene solvent to produce the Sn2 substitution product in 28 yield Saponification of the acetate ester is done by refluxing with potassium hydroxide in absolute ethanol to afford a 56 yield of the potassium salt intermediate This is then hydrolyzed with aqueous HCl and extracted to give an 81 yield of the carboxylic acid product Availability EditThis section does not cite any sources Please help improve this section by adding citations to reliable sources Unsourced material may be challenged and removed April 2020 Learn how and when to remove this template message A package of 10 mg cetirizine tablets Zyrtec D a combination of cetirizine and pseudoephedrine Formerly prescription only in many countries cetirizine is now available without prescription in most countries In some countries it is available over the counter only in packages containing seven or ten 10 mg doses Like many other antihistamine medications cetirizine is commonly prescribed in combination with pseudoephedrine a decongestant medical citation needed These combinations are often marketed using the same brand name as the cetirizine with a D suffix Zyrtec D Virlix D etc Cetirizine is marketed under the brand names Alatrol Alerid Alzene Cerchio Cetirin Cetriz Cetzine Cezin Cetgel Cirrus Histec Histazine Humex Letizen Okacet Cipla Reactine Razene Rigix Sensahist Oethmann South Africa Triz Zetop Zirtec Zirtek Zodac Zyllergy Zynor Zyrlek and Zyrtec Johnson amp Johnson among others References Edit a b c d e f g h Chen C 2008 Physicochemical pharmacological and pharmacokinetic properties of the zwitterionic antihistamines cetirizine and levocetirizine Curr Med Chem 15 21 2173 91 doi 10 2174 092986708785747625 PMID 18781943 a b c d e f g h i j k l m n o Simons FE Simons KJ 1999 Clinical pharmacology of new histamine H1 receptor antagonists Clin Pharmacokinet 36 5 329 52 doi 10 2165 00003088 199936050 00003 PMID 10384858 S2CID 21360079 a b c d e f g h i j k l m n o p q r s t Portnoy JM Dinakar C 2004 Review of cetirizine hydrochloride for the treatment of allergic disorders Expert Opin Pharmacother 5 1 125 35 doi 10 1517 14656566 5 1 125 PMID 14680442 S2CID 28946859 a b Simons FE 2002 Comparative pharmacology of H1 antihistamines clinical relevance Am J Med 113 Suppl 9A 9 38S 46S doi 10 1016 s0002 9343 02 01436 5 PMID 12517581 a b c d British national formulary BNF 76 76 ed Pharmaceutical Press 2018 p 279 ISBN 9780857113382 a b c d e Cetirizine Hydrochloride Monograph for Professionals Drugs com American Society of Health System Pharmacists Retrieved 3 March 2019 Cetirizine Pregnancy and Breastfeeding Warnings Drugs com Retrieved 3 March 2019 a b US patent 4525358 Baltes E De Lannoy J Rodriguez L 2 4 Diphenylmethyl 1 piperazinyl acetic acids and their amides issued 25 June 1985 assigned to UCB Pharmaceuticals Inc Fischer Jnos Ganellin C Robin 2006 Analogue based Drug Discovery John Wiley amp Sons p 549 ISBN 9783527607495 World Health Organization 2021 World Health Organization model list of essential medicines 22nd list 2021 Geneva World Health Organization hdl 10665 345533 WHO MHP HPS EML 2021 02 The Top 300 of 2019 ClinCalc Retrieved 16 October 2021 Cetirizine Drug Usage Statistics ClinCalc Retrieved 16 October 2021 a b Rang H P Rang and Dale s pharmacology Dale M Maureen Flower R J Rod J 1945 Henderson G Graeme Eighth ed United Kingdom p 332 ISBN 978 0 7020 5362 7 OCLC 903083639 a b CETIRIZINE HYDROCHLORIDE Retrieved 17 October 2020 Zyrtec Side Effects drugs com Drugs com Retrieved 21 August 2015 Ekhart C Van Der Horst P Van Hunsel F 2016 Unbearable Pruritus After Withdrawal of Levo cetirizine Drug Safety Case Reports 3 1 16 doi 10 1007 s40800 016 0041 9 PMC 5124431 PMID 27889900 Cetirizine Zyrtec Withdrawal amp Unbearable Itching People s Pharmacy Retrieved 9 September 2017 permanent dead link addicted to zyrtec MedHelp Retrieved 9 September 2017 Zhang L Cheng L Hong J 2013 The clinical use of cetirizine in the treatment of allergic rhinitis Pharmacology 92 1 2 14 25 doi 10 1159 000351843 PMID 23867423 Orzechowski RF Currie DS Valancius CA 2005 Comparative anticholinergic activities of 10 histamine H1 receptor antagonists in two functional models Eur J Pharmacol 506 3 257 64 doi 10 1016 j ejphar 2004 11 006 PMID 15627436 Taglialatela M Pannaccione A Castaldo P Giorgio G Zhou Z January CT Genovese A Marone G Annunziato L 1998 Molecular basis for the lack of HERG K channel block related cardiotoxicity by the H1 receptor blocker cetirizine compared with other second generation antihistamines Mol Pharmacol 54 1 113 21 doi 10 1124 mol 54 1 113 PMID 9658196 Hulhoven R Rosillon D Letiexhe M Meeus MA Daoust A Stockis A 2007 Levocetirizine does not prolong the QT QTc interval in healthy subjects results from a thorough QT study Eur J Clin Pharmacol 63 11 1011 7 doi 10 1007 s00228 007 0366 5 PMID 17891537 S2CID 36218027 The equivalent dose of 60 mg cetirizine is also the highest dose ever administered in healthy subjects 13 Gupta A Chatelain P Massingham R Jonsson EN Hammarlund Udenaes M February 2006 Brain distribution of cetirizine enantiomers comparison of three different tissue to plasma partition coefficients K p K p u and K p uu Drug Metab Dispos 34 2 318 23 doi 10 1124 dmd 105 007211 PMID 16303872 S2CID 9111905 a b c Tashiro M Kato M Miyake M Watanuki S Funaki Y Ishikawa Y Iwata R Yanai K 2009 Dose dependency of brain histamine H 1 receptor occupancy following oral administration of cetirizine hydrochloride measured using PET with 11C doxepin Hum Psychopharmacol 24 7 540 8 doi 10 1002 hup 1051 PMID 19697300 S2CID 5596000 van den Elzen MT van Os Medendorp H van den Brink I van den Hurk K Kouznetsova OI Lokin AS Laheij de Boer AM Rockmann H Bruijnzeel Koomen CA Knulst AC 2017 Effectiveness and safety of antihistamines up to fourfold or higher in treatment of chronic spontaneous urticaria Clin Transl Allergy 7 4 doi 10 1186 s13601 017 0141 3 PMC 5309999 PMID 28289538 30 mg of hydroxyzine equals about 10 mg cetirizine 11 Yanai K Tashiro M 2007 The physiological and pathophysiological roles of neuronal histamine an insight from human positron emission tomography studies Pharmacol Ther 113 1 1 15 doi 10 1016 j pharmthera 2006 06 008 PMID 16890992 Koller M Hilger RA Rihoux JP Konig W May 1996 Cetirizine exerts anti inflammatory effects on human neutrophils International Archives of Allergy and Immunology 110 1 52 6 doi 10 1159 000237310 PMID 8645978 Bielory L Lien KW Bigelsen S 2005 Efficacy and tolerability of newer antihistamines in the treatment of allergic conjunctivitis Drugs 65 2 215 28 doi 10 2165 00003495 200565020 00004 PMID 15631542 S2CID 46791611 Walsh GM January 1994 The anti inflammatory effects of cetirizine Clinical and Experimental Allergy Journal of the British Society for Allergy and Clinical Immunology 24 1 81 5 doi 10 1111 j 1365 2222 1994 tb00921 x PMID 8156449 S2CID 32269456 Gelfand EW Appajosyula S Meeves S January 2004 Anti inflammatory activity of H1 receptor antagonists review of recent experimental research Current Medical Research and Opinion 20 1 73 81 doi 10 1185 030079903125002586 PMID 14741075 S2CID 20451677 Fumagalli F Baiardini I Pasquali M Compalati E Guerra L Massacane P Canonica GW August 2004 Antihistamines do they work Further well controlled trials involving larger samples are needed Allergy 59 Suppl 78 74 7 doi 10 1111 j 1398 9995 2004 00573 x PMID 15245363 S2CID 39936983 Grob JJ Castelain M Richard MA Bonniol JP Beraud V Adhoute H Guillou N Bonerandi JJ May 1998 Antiinflammatory properties of cetirizine in a human contact dermatitis model Clinical evaluation of patch tests is not hampered by antihistamines Acta Dermato venereologica 78 3 194 7 doi 10 1080 000155598441512 PMID 9602225 a b Boone M Lespagnard L Renard N Song M Rihoux JP July 2000 Adhesion molecule profiles in atopic dermatitis vs allergic contact dermatitis pharmacological modulation by cetirizine J Eur Acad Dermatol Venereol 14 4 263 6 doi 10 1046 j 1468 3083 2000 00017 x PMID 11204513 S2CID 24026684 Archived from the original on 5 January 2013 Retrieved 19 November 2009 a b Pasko P Rodacki T Domagala Rodacka R Palimonka K Marcinkowska M Owczarek D 2017 Second generation H1 antihistamines interaction with food and alcohol A systematic review Biomed Pharmacother 93 27 39 doi 10 1016 j biopha 2017 06 008 PMID 28622592 Zyrtec prescribing information PDF May 2006 Archived from the original PDF on 4 January 2010 Retrieved 19 November 2009 Massoud Mahmoudi 2 June 2016 Allergy and Asthma Practical Diagnosis and Management Springer pp 574 ISBN 978 3 319 30835 7 External links Edit Cetirizine Drug Information Portal U S National Library of Medicine Cetirizine Tablet Uses In Hindi Retrieved from https en wikipedia org w index php title Cetirizine amp oldid 1050496518, wikipedia, wiki, book,

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