{"ATC Code":"N05BB01","Abbreviation":[],"Absorption, Distribution and Excretion":"The absolute bioavailability of hydroxyzine has not been ascertained, as intravenous formulations are unavailable due to a risk of hemolysis. Hydroxyzine is rapidly absorbed from the gastrointestinal tract upon oral administration, reaching its maximum plasma concentration (Tmax) approximately 2 hours following administration.","Aliases":["Hydroxyzine","68-88-2","Hydroxizine","Hydroxyzin","Hydroxine","Hydroxycine","Tranquizine","Ataraxoid","Hychotine","Tran-Q","Hydroxizinum","Atarazoid","Neurozina","Atazina","Deinait","Fenarol","Pamazone","Paxistil","Placidol","Plaxidol","Atara","Aterax","neo-Calma","Idrossizina","Vesparaz-Wirkstoff","Hidroxizina","Hydroxyzinum","Hydroksyzyny","UCB 492","NP 212","Equipose","N-(4-Chlorobenzhydryl)-N'-(hydroxyethoxyethyl)piperazine","1-(p-Chlorobenzhydryl)-4-(2-(2-hydroxyethoxy)ethyl)diethylenediamine","Ethanol, 2-(2-(4-((4-chlorophenyl)phenylmethyl)-1-piperazinyl)ethoxy)-","Vistazine","NSC-169188","30S50YM8OG","Dtxsid8023137","U.c.b-4492","N-(4-Chlorobenzhydryl)-N'-(hydroxyethyloxyethyl)piperazine","1-(p-Chloro-α-phenylbenzyl)-4-(2-hydroxyethoxyethyl)piperazine","2-(2-(4-(p-Chloro-α-phenylbenzyl)-1-piperazinyl)ethoxy)ethanol","2-(2-{4-[(4-chlorophenyl)(phenyl)methyl]piperazin-1-yl}ethoxy)ethan-1-ol","Ethanol, 2-[2-[4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]-","CHEBI:5818","Dtxcid203137","2-(2-(4-((4-Chlorophenyl)phenylmethyl)-1-piperazinyl)ethoxy)ethanol","Ethanol, 2-(2-(4-(p-chloro-α-phenylbenzyl)-1-piperazinyl)ethoxy)-","NSC169188","2-[2-[4-[(4-chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]ethanol","1-(p-Chlorobenzhydryl)-4-[2-(2-hydroxyethoxy)ethyl]diethylenediamine","idroxizina","2-(2-(4-((4-chlorophenyl)(phenyl)methyl)piperazin-1-yl)ethoxy)ethan-1-ol","N05BB01","200-693-1","Marex","Nevrolaks","Traquizine","Vistaril","Atarox","Parenteral","Atarax base","Atarax","Hydroxyzyne","Hydroxyzine base","Hydroxyzine free base","U.C.B 4492","Mfcd00242772","2-(2-(4-((4-Chlorophenyl)(phenyl)methyl)piperazin-1-yl)ethoxy)ethanol","1-(p-Chlorobenzhydryl)-4-(2-(2-hydroxyethoxy)ethyl)piperazine","CHEMBL896","1-(p-Chlorodiphenylmethyl)-4-(2-(2-hydroxyethoxy)ethyl)piperazine","2-(2-{4-[(4-chlorophenyl)(phenyl)methyl]piperazin-1-yl}ethoxy)ethanol","2-[2-[4-[(4-chlorophenyl)-phenyl-methyl]piperazin-1-yl]ethoxy]ethanol","Ncgc00018255-04","UCB 4492","1-(p-Chlorobenzhydryl)-4-[2-(2-hydroxyethoxy)ethyl]piperazine","1-(p-Chlorodiphenylmethyl)-4-[2-(2-hydroxyethoxy)ethyl]piperazine","2-[2-[4-(p-Chloro-α-phenylbenzyl)-1-piperazinyl]ethoxy]ethanol","1-(p-Chloro-α-phenylbenzyl)-4-[2-[(2-hydroxyethoxy)ethyl]piperazine","2-(2-{4-[(4-Chloro-phenyl)-phenyl-methyl]-piperazin-1-yl}-ethoxy)-ethanol","Ethanol, 2-[2-[4-(p-chloro-α-phenylbenzyl)-1-piperazinyl]ethoxy]-","Cas-68-88-2","U.CB 4492","HSDB 3098","Einecs 200-693-1","NSC 169188","Brn 0321392","Unii-30s50ym8og","1-(p-Chloro-α-phenylbenzyl)-4-(2-((2-hydroxyethoxy)ethyl)piperazine","1-(p-Chloro-α-phenylbenzyl)-4-(2-(2-hydroxyethoxy)ethyl)piperazine","Hydroxyzine,","Disron","Durrax","Prestwick0_000133","Prestwick1_000133","Prestwick2_000133","Prestwick3_000133","Schembl4491","BSPBio_000206","5-23-01-00462","SPBio_002145","BPBio1_000228","GTPL7199","orb1306507","BDBM22875","HY-B0548R","HMS3604B10","HY-B0548","MSK10145","PXB48047","UCB-4492","Tox21_113569","BBL034752","EBC-26843","STL417960","2-[(2-{4-[(4-chlorophenyl)(phenyl)methyl]piperazin-1-yl}ethyl)oxy]ethanol","Akos003334349","Akos016843978","Tox21_113569_1","DB00557","Mrf-0000015","Ncgc00018255-02","Ncgc00018255-03","Ncgc00018255-06","Ncgc00021152-06","Ncgc00089816-03","AS-81900","ST059726","Wln: t6n dntj ayr\u0026r d6\u0026 d2o2q","DB-049942","AB00053485","NS00002988","C07045","D08054","En300-708786","W13117","Ab00053485_24","Ab00053485_25","242H772","L000930","Q421937","Brd-a62428732-096-02-6","Brd-a62428732-096-10-9","Brd-a62428732-300-03-0","Brd-a62428732-300-06-3","1-(4-Chloro-α-phenylbenzyl)-4-((2-(2-hydroxyethoxy)ethyl)piperazine)","1-(p-Chloro-?-phenylbenzyl)-4-[2-(2-hydroxyethoxy)ethyl)]piperazine","2-(2-(4-((4-Chlorophenyl)(phenyl)methyl)-piperazin-1-yl)ethoxy)ethanol","2-(2-(4-[(4-Chlorophenyl)(phenyl)methyl]-1-piperazinyl)ethoxy)ethanol #","2-(2-{4-[(4-chlorophenyl)phenylmethyl]piperazinyl}ethoxy)ethan-1-ol","2-(2-(4-(P-chloro-α-phenylbenzyl)-1-piperazinyl)ethoxy)ethanol","1-(P-chloro-α-phenylbenzyl)-4-(2-((2-hydroxyethoxy)ethyl))piperazine","Ethanol, 2-(2-(4-((4-chlorophenyl)phenylmethyl)-1-piperazinyl)ethoxy)-,(+/-)-","Ethanol, 2-(2-(4-(4-chloro-α-phenylbenzyl)-1-piperazinyl)ethoxy)-"],"Biological Half-Life":"The half-life of hydroxyzine is reportedly 14-25 hours, and appears to be, on average, shorter in children (~7.1 hours) than in adults (~20 hours). Elimination half-life is prolonged in the elderly, averaging approximately 29 hours, and is likely to be similarly prolonged in patients with renal or hepatic impairment.","Boiling Point":"220 °C","CAS":"68-88-2","Chemical Classes":"Pharmaceutical","ChemicalClasses":["α-alkylbenzylamine"],"Chirality":"racemic","Color/Form":"Oil","Drug Classes":["Breast Feeding","Lactation","Milk, Human","Antihistamines","Antipruritics"],"Drug Indication":"Hydroxyzine is indicated for the symptomatic relief of anxiety and tension associated with psychoneuroses, and as an adjunct in organic disease states in which anxiety is manifested. It is also indicated in the treatment of histamine-mediated pruritus and pruritus due to allergic conditions such as chronic urticaria.  Canadian labeling states that hydroxyzine is also indicated in adults and children as a premedication prior to medical procedures, such as dental surgery. It is also used in the control of nausea and vomiting, excluding nausea and vomiting of pregnancy.","Drug Warnings":"Marked local discomfort, sterile abcesses, erythema, local irritation, and tissue necrosis may occur at the site of IM injection, and marked localized subcutaneous tissue induration has been reported as a result of extravasation of the drug.","EliminationHalfLife":"Adults: 20.0 hoursElderly: 29.3\u0026nbsp;hoursChildren: 7.1 hours","Esters":[],"European Community (EC) Number":"200-693-1","FDA Pharmacological Classification":"30S50YM8OG","Formating":[],"HMDB ID":"HMDB0014697","HeavyAtomCount":26,"Human Drugs":"Breast Feeding; Lactation; Milk, Human; Antihistamines; Antipruritics","IUPACName":"2-[2-[4-[(4-chlorophenyl)-phenylmethyl]piperazin-1-yl]ethoxy]ethanol","Impurities":"(RS)-1-[(4-clorophenyl)phenylmethyl]piperazine","InChI":"InChI=1S/C21H27ClN2O2/c22-20-8-6-19(7-9-20)21(18-4-2-1-3-5-18)24-12-10-23(11-13-24)14-16-26-17-15-25/h1-9,21,25H,10-17H2","InChIKey":"ZQDWXGKKHFNSQK-UHFFFAOYSA-N","Interactions":"Hydroxyzine has been shown to inhibit and reverse the vasopressor effect of epinephrine. If a vasopressor agent is required in patients receiving hydroxyzine, norepinephrine or metaraminol should be used; epinephrine should not be used.","MeSH Pharmacological Classification":"Agents, usually topical, that relieve itching (pruritus).","Mechanism of Action":"The H\u003csub\u003e1\u003c/sub\u003e histamine receptor is responsible for mediating hypersensitivity and allergic reactions. Exposure to an allergen results in degranulation of mast cells and basophils, which then release histamine and other inflammatory mediators. Histamine binds to, and activates, H\u003csub\u003e1\u003c/sub\u003e receptors, which results in the further release of pro-inflammatory cytokines, such as interleukins, from basophils and mast cells. These downstream effects of histamine binding are responsible for a wide variety of allergic symptoms, such as pruritus, rhinorrhea, and watery eyes.  Hydroxyzine is a potent inverse agonist of histamine H\u003csub\u003e1\u003c/sub\u003e-receptors - inverse agonists are agents that are considered to have a \"negative efficacy\", so rather than simply blocking activity at a receptor they actively dampen its activity. Inverse agonism at these receptors is responsible for hydroxyzine's efficacy in the treatment of histaminic edema, flare, and pruritus.  Hydroxyzine is not a cortical depressant, so its sedative properties likely occur at the subcortical level of the CNS. These sedative properties allow activity as an anxiolytic. Antiemetic efficacy is likely secondary to activity at off-targets.","Melting Point":"200C","Metabolism/Metabolites":"Hydroxyzine is metabolized in the liver by CYP3A4 and CYP3A5. While the precise metabolic fate of hydroxyzine is unclear, its main and active metabolite (~45 to 60% of an orally administered dose), generated by oxidation of its alcohol moiety to a carboxylic acid, is the second-generation antihistamine [cetirizine]. Hydroxyzine is likely broken down into several other metabolites, though specific structures and pathways have not been elucidated in humans.","MolecularFormula":"C\u003csub\u003e21\u003c/sub\u003eH\u003csub\u003e27\u003c/sub\u003eClN\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003e","MolecularWeight":"374.9 g/mol","Non-Human Toxicity Values":"LD50 Rat oral 840 mg/kg","Opticalactivity":"( + / - )","Pharmacodynamics":"Hydroxyzine blocks the activity of histamine to relieve allergic symptoms such as pruritus. Activity at off-targets also allows for its use as a sedative anxiolytic and an antiemetic in certain disease states.  Hydroxyzine is relatively fast-acting, with an onset of effect that occurs between 15 and 60 minutes and a duration of action between 4-6 hours. Hydroxyzine may potentiate the effects of central nervous system (CNS) depressants following general anesthesia - patients maintained on hydroxyzine should receive reduced doses of any CNS depressants required. Hydroxyzine is reported to prolong the QT/QTc interval based on postmarketing reports of rare events of Torsade de Pointes, cardiac arrest, and sudden death, and should be used with caution in patients with an increased baseline risk for QTc prolongation.","Physical Description":"Solid","PubChemId":3658,"Record Description":["LiverTox|Respiratory|Allergy symptoms|Antihistamine"],"Records":{"UNII":{"Impurities":[]}},"RefChem":"5897","RefCount":3,"RefCur":"","References":[{"Name":"Wikipedia","Urls":[{"Link":"https://en.wikipedia.org/wiki/Hydroxyzine","Name":"Hydroxyzine","Sub":false}]},{"Name":"Wikidata","Urls":[{"Link":"https://www.wikidata.org/wiki/Q421937","Name":"Hydroxyzine","Sub":false}]},{"Name":"DrugBank","Urls":[{"Link":"https://go.drugbank.com/drugs/DB00557","Name":"Hydroxyzine","Sub":false}]},{"Name":"PubChem","Urls":[{"Link":"https://pubchem.ncbi.nlm.nih.gov/compound/3658","Name":"Hydroxyzine","Sub":false}]},{"Name":"Common Chemistry","Urls":[{"Link":"https://commonchemistry.cas.org/detail?cas_rn=68-88-2","Name":"Hydroxyzine","Sub":false}]},{"Name":"HMDB","Urls":[{"Link":"https://hmdb.ca/metabolites/HMDB0014697","Name":"Hydroxyzine","Sub":false}]},{"Name":"KEGG","Urls":[{"Link":"https://www.kegg.jp/entry/C07045","Name":"Hydroxyzine","Sub":false}]},{"Name":"UNII","Urls":[{"Link":"https://gsrs.ncats.nih.gov/ginas/app/ui/substances/30S50YM8OG","Name":"Hydroxyzine","Sub":false}]},{"Name":"EPA DSSTox","Urls":[{"Link":"https://comptox.epa.gov/dashboard/chemical/details/DTXSID8023137","Name":"Hydroxyzine","Sub":false}]}],"Refs":["National Center for Biotechnology Information. PubChem Compound Summary for CID 3658, Hydroxyzine. Accessed January 5, 2026. \u003ca href=https://pubchem.ncbi.nlm.nih.gov/compound/3658\u003ehttps://pubchem.ncbi.nlm.nih.gov/compound/3658\u003c/a\u003e","U.S. Food and Drug Administration; National Center for Advancing Translational Sciences. Hydroxyzine. UNII: 30S50YM8OG. Global Substance Registration System. Accessed January 5, 2026. \u003ca href=https://gsrs.ncats.nih.gov/ginas/app/beta/substances/30S50YM8OG\u003ehttps://gsrs.ncats.nih.gov/ginas/app/beta/substances/30S50YM8OG\u003c/a\u003e"],"SMILES":"C1CN(CCN1CCOCCO)C(C2=CC=CC=C2)C3=CC=C(C=C3)Cl","SaltData":[],"Salts":[],"Scheduling":[{"gov":"Australia","ref":[],"schedule":"S4 substance"},{"gov":"Canada","ref":[],"schedule":"prescription only substance"},{"gov":"European Union","ref":[],"schedule":"prescription only substance"},{"gov":"United Kingdom","ref":[],"schedule":"prescription only substance"},{"gov":"United States","ref":[],"schedule":"prescription only substance"}],"Solubility":"Crystals; MP 193 °C; Bitter taste. Solubility in mg/mL: water \u003c700; chloroform 60; acetone 2; ether \u003c0.1. Solutions are unstable to intense UV light. /Hydroxyzine dihydrochloride/","StereoisomerData":[],"StereoisomerType":"enantiomer","Stereoisomers":[],"Structure":"\u003csvg xmlns=\"http://www.w3.org/2000/svg\" preserveAspectRatio=\"none\" style=\"display:block\" viewBox=\"0 0 166.569 97.946\"\u003e\u003crect width=\"100%\" height=\"100%\" fill=\"#fff\"/\u003e\u003cdesc\u003eGenerated by the Chemistry Development Kit (http://github.com/cdk)\u003c/desc\u003e\u003cg fill=\"#ff0d0d\" stroke=\"#000\" stroke-linecap=\"round\" stroke-linejoin=\"round\" stroke-width=\".7\"\u003e\u003cpath fill=\"#fff\" stroke=\"none\" d=\"M0 0h167v98H0z\"/\u003e\u003cg class=\"mol\"\u003e\u003cpath d=\"m80.252 72.004-13.209-7.617M67.043 64.387l-10.054 5.802M53.837 75.859l.001 11.39M53.838 87.249l13.21 7.618M67.048 94.867l10.053-5.803M80.252 72.004l.002 11.391M83.408 89.065l10.045 5.799M93.453 94.864l13.198-7.62M106.651 87.244l9.914 5.724M123.127 92.972l9.92-5.728M133.047 87.244l13.199 7.62M146.246 94.864l9.917-5.725M50.683 70.188l-10.045-5.799M40.638 64.389l-13.198 7.62\" class=\"bond\"/\u003e\u003cg class=\"bond\"\u003e\u003cpath d=\"M27.44 72.009 14.236 64.38M25.002 73.416l-10.766-6.22\"/\u003e\u003c/g\u003e\u003cpath d=\"M14.236 64.38 1.038 72\" class=\"bond\"/\u003e\u003cg class=\"bond\"\u003e\u003cpath d=\"m1.038 72 .005 15.249M3.477 73.408l.004 12.433\"/\u003e\u003c/g\u003e\u003cpath d=\"m1.043 87.249 13.203 7.628\" class=\"bond\"/\u003e\u003cg class=\"bond\"\u003e\u003cpath d=\"m14.246 94.877 13.198-7.62M14.247 92.061l10.759-6.211\"/\u003e\u003c/g\u003e\u003cpath d=\"m27.44 72.009.004 15.248M40.638 64.389v-15.24\" class=\"bond\"/\u003e\u003cg class=\"bond\"\u003e\u003cpath d=\"m27.595 41.594 13.043 7.555M30.026 40.184l10.612 6.147\"/\u003e\u003c/g\u003e\u003cpath d=\"m27.595 41.594-.077-15.24\" class=\"bond\"/\u003e\u003cg class=\"bond\"\u003e\u003cpath d=\"m40.484 18.567-12.966 7.787M40.513 21.395 29.964 27.73\"/\u003e\u003c/g\u003e\u003cpath d=\"m40.484 18.567 13.348 7.655\" class=\"bond\"/\u003e\u003cg class=\"bond\"\u003e\u003cpath d=\"m53.909 41.462-.077-15.24M51.463 40.06l-.062-12.421\"/\u003e\u003c/g\u003e\u003cpath d=\"m40.638 49.149 13.271-7.687M40.484 18.567 40.37 7.246\" class=\"bond\"/\u003e\u003cpath fill=\"#3050f8\" stroke=\"none\" d=\"M55.777 74.458h-.721l-2.619-4.066h-.03l.03.596q.024.357.024.732v2.738h-.566v-4.899h.715l2.607 4.054h.03l-.018-.327-.024-.477q-.006-.262-.006-.482v-2.768h.578zM82.195 89.694h-.72l-2.62-4.066h-.029l.029.595q.024.358.024.733v2.738h-.565v-4.899h.714l2.608 4.054h.029l-.018-.328-.023-.476q-.006-.262-.006-.482v-2.768h.577z\" class=\"atom\"/\u003e\u003cpath stroke=\"none\" d=\"M122.108 94.861q0 .756-.256 1.328-.256.566-.756.881t-1.244.316q-.756 0-1.262-.316-.506-.315-.756-.887-.244-.571-.244-1.333 0-.751.244-1.31.25-.566.756-.881t1.274-.316q.732 0 1.232.316.5.309.756.875.256.565.256 1.327m-3.863 0q0 .923.387 1.459.393.53 1.22.53.839 0 1.22-.53.387-.536.387-1.459 0-.928-.387-1.452-.381-.524-1.208-.524-.833 0-1.226.524t-.393 1.452\" class=\"atom\"/\u003e\u003cg stroke=\"none\" class=\"atom\"\u003e\u003cpath d=\"M161.703 87.241q0 .756-.256 1.328-.256.566-.756.881t-1.244.316q-.756 0-1.262-.316-.506-.315-.756-.887-.244-.571-.244-1.333 0-.751.244-1.31.25-.566.756-.881t1.274-.316q.732 0 1.232.316.5.309.756.875.256.565.256 1.327m-3.864 0q0 .923.387 1.459.393.53 1.221.53.839 0 1.22-.53.387-.536.387-1.459 0-.928-.387-1.452-.381-.524-1.208-.524-.834 0-1.227.524t-.393 1.452M166.009 89.694h-.619v-2.286h-2.512v2.286h-.613v-4.899h.613v2.071h2.512v-2.071h.619z\"/\u003e\u003c/g\u003e\u003cpath fill=\"#1ff01f\" stroke=\"none\" d=\"M40.825 1.352q-.786 0-1.239.53-.452.523-.452 1.446 0 .911.417 1.447.422.53 1.268.53.321 0 .607-.054.292-.059.565-.143v.536q-.273.101-.565.149-.292.053-.697.053-.744 0-1.25-.309-.5-.31-.75-.875-.25-.572-.25-1.34 0-.744.268-1.309.274-.566.804-.881.529-.322 1.28-.322.779 0 1.351.286l-.244.524q-.226-.102-.506-.185-.274-.083-.607-.083m2.756 4.423h-.601V.56h.601z\" class=\"atom\"/\u003e\u003cpath stroke=\"#3050f8\" d=\"m56.989 70.189 5.027-2.901M53.837 75.859l.001 5.695M77.101 89.064l-5.026 2.901M80.254 83.395l-.001-5.695M83.408 89.065l5.022 2.9\" class=\"hi\"/\u003e\u003cpath stroke=\"#ff0d0d\" d=\"m116.565 92.968-4.957-2.862M123.127 92.972l4.96-2.864M156.163 89.139l-4.959 2.862\" class=\"hi\"/\u003e\u003cpath stroke=\"#3050f8\" d=\"m50.683 70.188-5.023-2.9\" class=\"hi\"/\u003e\u003cpath stroke=\"#1ff01f\" d=\"m40.37 7.246.057 5.661\" class=\"hi\"/\u003e\u003c/g\u003e\u003c/g\u003e\u003c/svg\u003e","Therapeutic Uses":"Anti-Anxiety Agents; Antiemetics; Antipruritics; Histamine H1 Antagonists; Sedatives, Nonbarbiturate","Title":"Hydroxyzine","Toxicity Data":"Oral, rat LD\u003csub\u003e50\u003c/sub\u003e: 950 mg/kg. ","Treatment":"If vomiting has not occurred spontaneously, it should be induced. Immediate gastric lavage is also recommended. General supportive care, including frequent monitoring of the vital signs and close observation of the patient, is indicated. Hypotension, though unlikely, may be controlled with intravenous fluids and norepinephrine or metaraminol. Do not use epinephrine as hydroxyzine hydrochloride counteracts its pressor action. There is no specific antidote. It is doubtful that hemodialysis would be of any value in the treatment of overdosage with hydroxyzine. However, if other agents such as barbiturates have been ingested concomitantly, hemodialysis may be indicated. (L1712)","UNII":"30S50YM8OG","Wikidata":"Q421937","Wikipedia":"Hydroxyzine","XLogP":3.7}