Title: Chlorhexidine
CAS Registry Number: 55-56-1
CAS Name: N,N¢¢-Bis(4-chlorophenyl)-3,12-diimino-2,4,11,13-tetraazatetradecanediimidamide
Additional Names: 1,1¢-hexamethylenebis[5-(p-chlorophenyl)biguanide]; 1,6-bis[N¢-(p-chlorophenyl)-N5-biguanido]hexane; 1,6-bis(N5-p-chlorophenyl-N¢-diguanido)hexane; 1,6-di(4¢-chlorophenyldiguanido)hexane
Manufacturers' Codes: 10040
Molecular Formula: C22H30Cl2N10
Molecular Weight: 505.45
Percent Composition: C 52.28%, H 5.98%, Cl 14.03%, N 27.71%
Literature References: Bisbiguanide with bacteriostatic activity. Prepn: Rose, Swain, J. Chem. Soc. 1956, 4422; eidem, US 2684924 (1954 to I.C.I.). Antibacterial activity and acute toxicity: G. E. Davies et al., Br. J. Pharmacol. 9, 192 (1954). Review of toxicology and clinical uses: D. M. Foulkes, J. Periodontal Res. 8, Suppl. 12, 55-60 (1973). Series of articles on clinical efficacy in gingivitis and plaque control: ibid. 21, Suppl. 16, 1-89 (1986).
Properties: Crystals from methanol, mp 134°. Strong alkaline reaction. Soly in water at 20°: 0.08% (w/v).
Melting point: mp 134°
Derivative Type: Dihydrochloride
CAS Registry Number: 3697-42-5
Trademarks: Lisium (Brunton)
Molecular Formula: C22H30Cl2N10.2HCl
Molecular Weight: 578.37
Percent Composition: C 45.69%, H 5.58%, Cl 24.52%, N 24.22%
Properties: Crystals, dec 260-262°. Soly in water at 20°: 0.06 g/100 ml.
Derivative Type: Diacetate
CAS Registry Number: 56-95-1
Trademarks: Chlorasept 2000 (Baxter); Nolvasan (Fort Dodge)
Molecular Formula: C22H30Cl2N10.2C2H4O2
Molecular Weight: 625.55
Percent Composition: C 49.92%, H 6.12%, Cl 11.33%, N 22.39%, O 10.23%
Properties: Crystals, mp 154-155°. Neutral reaction. Soly in water at 20°: 1.9 g/100 ml. Aq solns dec when heated above 70°. Soluble in alcohol, glycerol, propylene glycol, polyethylene glycols. LD50 orally in mice: 2 g/kg (Davies).
Melting point: mp 154-155°
Toxicity data: LD50 orally in mice: 2 g/kg (Davies)
Derivative Type: D-Digluconate
CAS Registry Number: 18472-51-0
Trademarks: Chlorhexamed (Blendax-Richardson); Bacticlens (Smith & Nephew); Corsodyl (Fink); Gingisan (Chassot); Hibiclens (Zeneca); Hibident (SKB); Hibidil (Zeneca); Hibiscrub (Zeneca); Hibital (Zeneca); Hibitane (Zeneca); Peridex (Procter & Gamble); pHiso-Med; Plac Out (Bernabo); Rotersept (Roterpharma); Secalan (Zyma); Sterilon (Roter); Unisept (Schering)
Properties: Soly in water at 20°: >50% (w/v). LD50 in mice (mg/kg): 22 i.v.; 1800 orally (Foulkes).
Toxicity data: LD50 in mice (mg/kg): 22 i.v.; 1800 orally (Foulkes)
Therap-Cat: Antiseptic; disinfectant.
Therap-Cat-Vet: Antiseptic; disinfectant.
Keywords: Antiseptic/Disinfectant; Guanidines.
Chloric Acid Chlorimuron-ethyl Chlorinated Lime Chlorindanol Chlorine Dioxide

Systematic (IUPAC) name
N,N′′′′1,6-Hexanediylbis[N′-(4-chlorophenyl)(imidodicarbonimidic diamide)]
Clinical data
Trade names Avagard, BactoShield CHG, Betasept, ChloraPrep, Chlorostat, Dyna-Hex, Hibiclens, Hibistat, Operand Chlorhexidine Gluconate, Peridex, PerioChip, PerioGard
AHFS/ FDA Professional Drug Information
Legal status OTC (US)
CAS number 55-56-1 YesY
ATC code A01AB03 B05CA02, D08AC02, D09AA12 (dressing), R02AA05, S01AX09, S02AA09, S03AA04
PubChem CID 5353524
DrugBank DB00878
ChemSpider 2612 YesY
KEGG D07668 YesY
Synonyms 1,6-bis(4-chloro-phenylbiguanido)hexan
Chemical data
Formula C22H30Cl2N10 
Mol. mass 505.446 g/mol
Physical data
Solubility in water 0.0008 mg/mL (20 °C)
 YesY (what is this?)  (verify)

Chlorhexidine is a cationic polybiguanide (bisbiguanide). It is used primarily as its salts (e.g., the dihydrochloride, diacetate and digluconate).