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Record Information
Creation Date2009-07-21 20:27:02 UTC
Update Date2014-12-24 20:25:51 UTC
Accession NumberT3D2810
Common NameCimetidine
ClassSmall Molecule
DescriptionA histamine congener, it competitively inhibits histamine binding to histamine H2 receptors. Cimetidine has a range of pharmacological actions. It inhibits gastric acid secretion, as well as pepsin and gastrins output. It also blocks the activity of cytochrome P-450 which might explain proposals for use in neoadjuvant therapy.
Compound Type
  • Adjuvant
  • Amide
  • Amine
  • Analgesic
  • Anti-Ulcer Agent
  • Drug
  • Enzyme Inhibitor
  • Ether
  • Histamine Antagonist
  • Histamine H2 Antagonist
  • Metabolite
  • Nitrile
  • Organic Compound
  • Synthetic Compound
Chemical Structure
Cimetidine Hcl
Tagamet HB
Tagamet hb 200
Tagamet HB200
Chemical FormulaC10H16N6S
Average Molecular Mass252.339 g/mol
Monoisotopic Mass252.116 g/mol
CAS Registry Number51481-61-9
IUPAC Name(Z)-N-cyano-N''-methyl-N'-(2-{[(5-methyl-1H-imidazol-4-yl)methyl]sulfanyl}ethyl)guanidine
Traditional Nametagamet HB
InChI IdentifierInChI=1S/C10H16N6S/c1-8-9(16-7-15-8)5-17-4-3-13-10(12-2)14-6-11/h7H,3-5H2,1-2H3,(H,15,16)(H2,12,13,14)
Chemical Taxonomy
Description belongs to the class of organic compounds known as imidazoles. Imidazoles are compounds containing an imidazole ring, which is an aromatic five-member ring with two nitrogen atoms at positions 1 and 3, and three carbon atoms.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
Sub ClassImidazoles
Direct ParentImidazoles
Alternative Parents
  • Imidazole
  • Heteroaromatic compound
  • Guanidine
  • Thioether
  • Carboximidamide
  • Sulfenyl compound
  • Propargyl-type 1,3-dipolar organic compound
  • Organic 1,3-dipolar compound
  • Dialkylthioether
  • Azacycle
  • Organic nitrogen compound
  • Organopnictogen compound
  • Imine
  • Organonitrogen compound
  • Organosulfur compound
  • Hydrocarbon derivative
  • Aromatic heteromonocyclic compound
Molecular FrameworkAromatic heteromonocyclic compounds
External Descriptors
Biological Properties
StatusDetected and Not Quantified
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Membrane
Biofluid LocationsNot Available
Tissue LocationsNot Available
Cimetidine PathwayNot AvailableNot Available
Biological Roles
Chemical Roles
Physical Properties
AppearanceWhite powder.
Experimental Properties
Melting Point142°C
Boiling PointNot Available
Solubility9380 mg/L (at 25°C)
Predicted Properties
Water Solubility0.82 g/LALOGPS
pKa (Strongest Acidic)13.38ChemAxon
pKa (Strongest Basic)6.91ChemAxon
Physiological Charge1ChemAxon
Hydrogen Acceptor Count5ChemAxon
Hydrogen Donor Count3ChemAxon
Polar Surface Area88.89 ŲChemAxon
Rotatable Bond Count5ChemAxon
Refractivity70.32 m³·mol⁻¹ChemAxon
Polarizability27.47 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash Key
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0005-9500000000-8ff5fa28797a788c95beView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-qTof , Positivesplash10-0002-9511000000-75fc9243ad1eb9c79cb4View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0a4j-5900000000-122f9dbdf583bbe3dee8View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0002-9300000000-39ee157d9e264867cfa4View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0002-9000000000-6e876a668444c8277412View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0002-9000000000-85640be9b2799889fd02View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0002-9000000000-9b8d3eafde213bee6396View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0a4j-9000000000-b47e11697992a843f5e4View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0a4i-9000000000-75ebe86c90f5ed341c57View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0aor-9000000000-d7302885bef7454b4db2View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-014i-9000000000-b2f3ab1b5ae1e2f8f8bbView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-0a4i-0930000000-dbae8348b5c999cc664dView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-052b-9600000000-8b4b94cd7303c9b9a0efView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-0002-9000000000-c23b62afdf4dff8c43dbView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-0002-9000000000-e477cd71a628f6adaf46View in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-052e-9000000000-61584ad991262d50a01bView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , positivesplash10-0zfr-1980000000-84e04b032e6f422e5b6bView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , positivesplash10-0aos-2900000000-e8d9297512335ce612fbView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , positivesplash10-052b-9800000000-7235208cf21d7ea1f7adView in MoNA
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , positivesplash10-0002-9300000000-4996f6630fe29fccd7d1View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0ufs-7790000000-535b3b79ad51bbf5a724View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-056s-5910000000-059a8f3e3eb08432dd72View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0002-9100000000-ceadcc70f9905df3cd1bView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0ufs-7960000000-d054508682ae0a8a700dView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0adm-5910000000-05af2f300dae46b29b5fView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0006-9100000000-43451f5e853f064cd924View in MoNA
MSMass Spectrum (Electron Ionization)splash10-002b-9510000000-36ce01132725fd5bf5d8View in MoNA
1D NMR1H NMR SpectrumNot AvailableView in JSpectraViewer
Toxicity Profile
Route of ExposureOral, rapid 60-70%
Mechanism of ToxicityCimetidine binds to an H2-receptor located on the basolateral membrane of the gastric parietal cell, blocking histamine effects. This competitive inhibition results in reduced gastric acid secretion and a reduction in gastric volume and acidity.
MetabolismHepatic Route of Elimination: The principal route of excretion of cimetidine is the urine. Half Life: 2 hours
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)3, not classifiable as to its carcinogenicity to humans. (4)
Uses/SourcesFor the treatment and the management of acid-reflux disorders (GERD), peptic ulcer disease, heartburn, and acid indigestion.
Minimum Risk LevelNot Available
Health EffectsNot Available
SymptomsSymptoms of overdose include nausea, vomiting, diarrhea, increased saliva production, difficulty breathing, and a fast heartbeat.
TreatmentThe usual measures to remove unabsorbed material from the gastrointestinal tract, clinical monitoring and supportive therapy should be employed. (3)
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDDB00501
PubChem Compound ID2756
ChemSpider ID2654
UniProt IDNot Available
ChEBI ID3699
BioCyc IDNot Available
CTD IDNot Available
Stitch IDCimetidine
PDB IDNot Available
ACToR IDNot Available
Wikipedia LinkCimetidine
Synthesis Reference

Saburo Uchikuga, Tomoyasu Tashiro, Yasuko Osawa, “Process for preparing the H.sub.2 -receptor antagonist cimetidine.” U.S. Patent US4413129, issued March, 1972.

General References
  1. Michnovicz JJ, Galbraith RA: Cimetidine inhibits catechol estrogen metabolism in women. Metabolism. 1991 Feb;40(2):170-4. [1988774 ]
  2. [Link]
  3. RxList: The Internet Drug Index (2009). [Link]
  4. International Agency for Research on Cancer (2014). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. [Link]
Gene Regulation
Up-Regulated Genes
GeneGene SymbolGene IDInteractionChromosomeDetails
Down-Regulated GenesNot Available


General Function:
Histamine receptor activity
Specific Function:
The H2 subclass of histamine receptors mediates gastric acid secretion. Also appears to regulate gastrointestinal motility and intestinal secretion. Possible role in regulating cell growth and differentiation. The activity of this receptor is mediated by G proteins which activate adenylyl cyclase and, through a separate G protein-dependent mechanism, the phosphoinositide/protein kinase (PKC) signaling pathway (By similarity).
Gene Name:
Uniprot ID:
Molecular Weight:
40097.65 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory0.14 uMNot AvailableBindingDB 50403559
IC500.14 uMNot AvailableBindingDB 50403559
IC500.27 uMNot AvailableBindingDB 50403559
  1. Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. [11752352 ]
  2. Hernandez-Munoz R, Montiel-Ruiz C, Vazquez-Martinez O: Gastric mucosal cell proliferation in ethanol-induced chronic mucosal injury is related to oxidative stress and lipid peroxidation in rats. Lab Invest. 2000 Aug;80(8):1161-9. [10950107 ]
  3. Takahashi HK, Watanabe T, Yokoyama A, Iwagaki H, Yoshino T, Tanaka N, Nishibori M: Cimetidine induces interleukin-18 production through H2-agonist activity in monocytes. Mol Pharmacol. 2006 Aug;70(2):450-3. Epub 2006 May 24. [16723495 ]
  4. Kuint J, Linder N, Reichman B: Hypoxemia associated with cimetidine therapy in a newborn infant. Am J Perinatol. 1996 Jul;13(5):301-3. [8863950 ]
  5. Cappelli A, Manini M, Valenti S, Castriconi F, Giuliani G, Anzini M, Brogi S, Butini S, Gemma S, Campiani G, Giorgi G, Mennuni L, Lanza M, Giordani A, Caselli G, Letari O, Makovec F: Synthesis and structure-activity relationship studies in serotonin 5-HT(1A) receptor agonists based on fused pyrrolidone scaffolds. Eur J Med Chem. 2013 May;63:85-94. doi: 10.1016/j.ejmech.2013.01.044. Epub 2013 Feb 8. [23466604 ]
  6. Veinberg G, Vorona M, Zvejniece L, Vilskersts R, Vavers E, Liepinsh E, Kazoka H, Belyakov S, Mishnev A, Kuznecovs J, Vikainis S, Orlova N, Lebedev A, Ponomaryov Y, Dambrova M: Synthesis and biological evaluation of 2-(5-methyl-4-phenyl-2-oxopyrrolidin-1-yl)-acetamide stereoisomers as novel positive allosteric modulators of sigma-1 receptor. Bioorg Med Chem. 2013 May 15;21(10):2764-71. doi: 10.1016/j.bmc.2013.03.016. Epub 2013 Mar 24. [23582449 ]
  7. Nakai T, Kitamura N, Hashimoto T, Kajimoto Y, Nishino N, Mita T, Tanaka C: Decreased histamine H1 receptors in the frontal cortex of brains from patients with chronic schizophrenia. Biol Psychiatry. 1991 Aug 15;30(4):349-56. [1912125 ]
  8. Hosking MP, Lennon RL, Gronert GA: Combined H1 and H2 receptor blockade attenuates the cardiovascular effects of high-dose atracurium for rapid sequence endotracheal intubation. Anesth Analg. 1988 Nov;67(11):1089-92. [2461127 ]
  9. Alewijnse AE, Smit MJ, Hoffmann M, Verzijl D, Timmerman H, Leurs R: Constitutive activity and structural instability of the wild-type human H2 receptor. J Neurochem. 1998 Aug;71(2):799-807. [9681472 ]
General Function:
Sodium-independent organic anion transmembrane transporter activity
Specific Function:
Involved in the renal elimination of endogenous and exogenous organic anions. Functions as organic anion exchanger when the uptake of one molecule of organic anion is coupled with an efflux of one molecule of endogenous dicarboxylic acid (glutarate, ketoglutarate, etc). Mediates the sodium-independent uptake of 2,3-dimercapto-1-propanesulfonic acid (DMPS) (By similarity). Mediates the sodium-independent uptake of p-aminohippurate (PAH), ochratoxin (OTA), acyclovir (ACV), 3'-azido-3-'deoxythymidine (AZT), cimetidine (CMD), 2,4-dichloro-phenoxyacetate (2,4-D), hippurate (HA), indoleacetate (IA), indoxyl sulfate (IS) and 3-carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF), cidofovir, adefovir, 9-(2-phosphonylmethoxyethyl) guanine (PMEG), 9-(2-phosphonylmethoxyethyl) diaminopurine (PMEDAP) and edaravone sulfate. PAH uptake is inhibited by p-chloromercuribenzenesulphonate (PCMBS), diethyl pyrocarbonate (DEPC), sulindac, diclofenac, carprofen, glutarate and okadaic acid (By similarity). PAH uptake is inhibited by benzothiazolylcysteine (BTC), S-chlorotrifluoroethylcysteine (CTFC), cysteine S-conjugates S-dichlorovinylcysteine (DCVC), furosemide, steviol, phorbol 12-myristate 13-acetate (PMA), calcium ionophore A23187, benzylpenicillin, furosemide, indomethacin, bumetamide, losartan, probenecid, phenol red, urate, and alpha-ketoglutarate.
Gene Name:
Uniprot ID:
Molecular Weight:
61815.78 Da
  1. Burckhardt BC, Brai S, Wallis S, Krick W, Wolff NA, Burckhardt G: Transport of cimetidine by flounder and human renal organic anion transporter 1. Am J Physiol Renal Physiol. 2003 Mar;284(3):F503-9. Epub 2002 Nov 12. [12429554 ]
  2. Khamdang S, Takeda M, Shimoda M, Noshiro R, Narikawa S, Huang XL, Enomoto A, Piyachaturawat P, Endou H: Interactions of human- and rat-organic anion transporters with pravastatin and cimetidine. J Pharmacol Sci. 2004 Feb;94(2):197-202. [14978359 ]
  3. Hashimoto T, Narikawa S, Huang XL, Minematsu T, Usui T, Kamimura H, Endou H: Characterization of the renal tubular transport of zonampanel, a novel alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor antagonist, by human organic anion transporters. Drug Metab Dispos. 2004 Oct;32(10):1096-102. [15377641 ]
  4. Motohashi H, Uwai Y, Hiramoto K, Okuda M, Inui K: Different transport properties between famotidine and cimetidine by human renal organic ion transporters (SLC22A). Eur J Pharmacol. 2004 Oct 25;503(1-3):25-30. [15496291 ]
  5. Ueo H, Motohashi H, Katsura T, Inui K: Human organic anion transporter hOAT3 is a potent transporter of cephalosporin antibiotics, in comparison with hOAT1. Biochem Pharmacol. 2005 Oct 1;70(7):1104-13. [16098483 ]
General Function:
Steroid hydroxylase activity
Specific Function:
Responsible for the metabolism of many drugs and environmental chemicals that it oxidizes. It is involved in the metabolism of drugs such as antiarrhythmics, adrenoceptor antagonists, and tricyclic antidepressants.
Gene Name:
Uniprot ID:
Molecular Weight:
55768.94 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory77 uMNot AvailableBindingDB 50403559
  1. Fontana E, Dansette PM, Poli SM: Cytochrome p450 enzymes mechanism based inhibitors: common sub-structures and reactivity. Curr Drug Metab. 2005 Oct;6(5):413-54. [16248836 ]
General Function:
Monovalent cation:proton antiporter activity
Specific Function:
Solute transporter for tetraethylammonium (TEA), 1-methyl-4-phenylpyridinium (MPP), cimetidine, N-methylnicotinamide (NMN), metformin, creatinine, guanidine, procainamide, topotecan, estrone sulfate, acyclovir, ganciclovir and also the zwitterionic cephalosporin, cephalexin and cephradin. Seems to also play a role in the uptake of oxaliplatin (a new platinum anticancer agent). Able to transport paraquat (PQ or N,N-dimethyl-4-4'-bipiridinium); a widely used herbicid. Responsible for the secretion of cationic drugs across the brush border membranes.
Gene Name:
Uniprot ID:
Molecular Weight:
61921.585 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
IC501.2 uMNot AvailableBindingDB 50403559
  1. Wittwer MB, Zur AA, Khuri N, Kido Y, Kosaka A, Zhang X, Morrissey KM, Sali A, Huang Y, Giacomini KM: Discovery of potent, selective multidrug and toxin extrusion transporter 1 (MATE1, SLC47A1) inhibitors through prescription drug profiling and computational modeling. J Med Chem. 2013 Feb 14;56(3):781-95. doi: 10.1021/jm301302s. Epub 2013 Jan 22. [23241029 ]
General Function:
Xenobiotic-transporting atpase activity
Specific Function:
Energy-dependent efflux pump responsible for decreased drug accumulation in multidrug-resistant cells.
Gene Name:
Uniprot ID:
Molecular Weight:
141477.255 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
IC50>50 uMNot AvailableBindingDB 50403559
  1. Schwab D, Fischer H, Tabatabaei A, Poli S, Huwyler J: Comparison of in vitro P-glycoprotein screening assays: recommendations for their use in drug discovery. J Med Chem. 2003 Apr 24;46(9):1716-25. [12699389 ]