Chloropyramine

{{Short description|Chemical compound}}

{{more footnotes needed|date=June 2013}}

{{Drugbox

| Verifiedfields = changed

| Watchedfields = changed

| class = First-generation antihistamine

| verifiedrevid = 447430568

| IUPAC_name = N'-[(4-chlorophenyl)methyl]-N,N-dimethyl-N'-pyridin-2-ylethane-1,2-diamine

| image = Chloropyramine.svg

| width = 200

| tradename =

| Drugs.com = {{drugs.com|international|chloropyramine}}

| pregnancy_category = C{{where|date=November 2024}}

| legal_status = By mouth: OTC, Injection: Rx-only (RU)

| routes_of_administration = By mouth, intramuscular, topical

| bioavailability = ~100%{{cite web |title=Chloropyramine Tablets for Oral Use. Prescribing Information |url=http://grls.rosminzdrav.ru/ImgInstr.aspx?folder=ScanVavilova&Filepath=\Vneseno_v_Grls\454954\IP&idReg=160167&isOld=1&fileType=jpg&pfolder=2 |website=State Register of Medicines |publisher=Ozon OOO |access-date=5 January 2016 |language=ru}}

| metabolism = Extensive hepatic

| onset = 15–30 min (oral){{Cite web |title=Хлоропирамин (Chloropyraminum) |url=https://www.lsgeotar.ru/khloropiramin.html |language=ru}}

| elimination_half-life = ~14 hours

| excretion = Kidney

| CAS_number_Ref = {{cascite|correct|??}}

| CAS_number = 59-32-5

| ATC_prefix = D04

| ATC_suffix = AA09

| ATC_supplemental = {{ATC|R06|AC03}}

| ChEMBL_Ref = {{ebicite|changed|EBI}}

| ChEMBL = 1194287

| PubChem = 25295

| DrugBank_Ref = {{drugbankcite|correct|drugbank}}

| DrugBank = DB08800

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 23628

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = 2K3L8O9SOV

| KEGG_Ref = {{keggcite|correct|kegg}}

| KEGG = D07195

| C = 16

| H = 20

| Cl = 1

| N = 3

| smiles = Clc1ccc(cc1)CN(c2ncccc2)CCN(C)C

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/C16H20ClN3/c1-19(2)11-12-20(16-5-3-4-10-18-16)13-14-6-8-15(17)9-7-14/h3-10H,11-13H2,1-2H3

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = ICKFFNBDFNZJSX-UHFFFAOYSA-N

}}

Chloropyramine is a first-generation antihistamine drug approved in several Eastern European countries such as Russia for the treatment of allergic conjunctivitis, allergic rhinitis, bronchial asthma, and other atopic (allergic) conditions. Related indications for clinical use include angioedema, allergic reactions to insect bites, food and drug allergies, and anaphylactic shock.{{cn|date=November 2024}}

Chloropyramine is known as a competitive reversible H₁ receptor antagonist (also known as an H₁ inverse agonist), meaning that it exerts its pharmacological action by competing with histamine for the H₁ subtype histamine receptor. By blocking the effects of histamine, the drug inhibits the vasodilation, increased vascular permeability, and tissue edema associated with histamine release in the tissue. The H₁ antagonistic properties of chloropyramine can be used by researchers for the purposes of blocking the effects of histamine on cells and tissues. In addition, chloropyramine has some anticholinergic properties.

Chloropyramine's anticholinergic properties and the fact that it can pass through the blood–brain barrier are linked to its clinical side effects such as drowsiness, weakness, vertigo, fatigue, dry mouth, constipation, and rarely — visual disturbances and increase of intraocular pressure.{{cn|date=November 2024}}