Cetylpyridinium chloride

Cetylpyridinium chloride
IUPAC name 1-Hexadecylpyridinium chloride
Other names Acetoquat CPC; Pyrisept EXADECYL-PYRIDINIUM, CHLORIDE
Identifiers
CAS number	123-03-5 Y, 6004-24-6 (monohydrate)
PubChem	31239
ChemSpider	28979 Y
UNII	6BR7T22E2S Y
ChEBI	CHEBI:32915 Y
ChEMBL	CHEMBL34833 Y
ATC code	B05CA01, D08AJ03, D09AA07 (dressing), R02AA06
Beilstein Reference	3578606
Jmol-3D images	{{#if:[Cl-].[n+]1(ccccc1)CCCCCCCCCCCCCCCC|Image 1
SMILES [Cl-].[n+]1(ccccc1)CCCCCCCCCCCCCCCC
InChI InChI=1S/C21H38N.ClH/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-16-19-22-20-17-15-18-21-22;/h15,17-18,20-21H,2-14,16,19H2,1H3;1H/q+1;/p-1 Y Key: YMKDRGPMQRFJGP-UHFFFAOYSA-M Y InChI=1/C21H38N.ClH/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-16-19-22-20-17-15-18-21-22;/h15,17-18,20-21H,2-14,16,19H2,1H3;1H/q+1;/p-1 Key: YMKDRGPMQRFJGP-REWHXWOFAU
Properties
Molecular formula	C21H38ClN
Molar mass	339.99 g mol−1
Appearance	solid
Melting point	77 °C; 171 °F; 350 K
Hazards
LD50	36 mg/kg (rabbit, iv)[1] 400 mg/kg (rabbit, oral)[1] 6 mg/kg (rat, ip)[1] 30 mg/kg (rat, iv)[1] 200 mg/kg (rat, oral)[1] 250 mg/kg (rat, sc)[1] 10 mg/kg (mouse, ip)[1] 108 mg/kg (mouse, oral)[1]
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Cetylpyridinium chloride (CPC) is a cationic quaternary ammonium compound used in some types of mouthwashes, toothpastes, lozenges, throat sprays, breath sprays, and nasal sprays. It is an antiseptic that kills bacteria and other microorganisms. It has been shown to be effective in preventing dental plaque and reducing gingivitis.^[2][3] It has also been used as an ingredient in certain pesticides. Cetylpyridinium chloride may cause brown stains between the teeth and on the surface of teeth.^[4][5] However, these stains can be easily removed by a dental hygienist during a routine check-up.^[4][5]

Synonyms

Cetylpyridinium chloride is present in commercial products such as 1-palmitylpyridinium chloride, C16-alkylpyridinium chloride, 1-hexadecylpyridinium chloride, acetoquat CPC, aktivex, ammonyx CPC, cecure, ceepryn chloride, cepacol, ceprim, cepacol chloride, cetafilm, cetamium, dobendan, halset, ipanol, medilave, mercocet, merothol, pionin B, pristacin, pyrisept, and asept.

Physical and chemical properties

Cetylpyridinium chloride has the molecular formula C₂₁H₃₈NCl and at its pure form is in a solid state at room temperature. It has a melting point of 77 °C when anhydrous or 80–83 °C in its monohydrate form. It is insoluble in acetone, acetic acid, or ethanol. It has a pyridine-like odor. It is combustible. Concentrated solutions are destructive to mucous membranes. Its critical micelle concentration (CMC) is 0.00012M,^[6] and is strongly dependent on the salt concentration of the solution.

In some products, cetylpyridinium bromide is used instead. Its properties are virtually identical.

Toxicology and pharmacology

With intravenous infusion as the delivery mechanism, the LD₅₀ of cetylpyridinium chloride has been measured at 30 mg/kg in rats and 36 mg/kg in rabbits. Conversely, with oral administration LD₅₀ levels are higher, having been measured at 200 mg/kg in rats, 400 mg/kg in rabbits, and 108 mg/kg in mice.^[7]

Use in over-the-counter drugs

OTC products containing cetylpyridinium chloride include oral wash, oral rinse, as well as ingestable products (e.g. CPC lozenges).^[8] In addition, cough syrups containing CPC are also available as OTC medications.^[9]

The FDA monograph on oral antiseptic drug products reviewed the data regarding CPC and concluded the following: "The agency believes that the information contained in its adverse reaction files, 30 years of safe marketing of an OTC mouthwash containing cetylpyridinium chloride (NDA 14- 598), and the safety data evaluated by the Oral Cavity Panel are sufficient to conclude that 0.025 to 0.1 percent cetylpyridinium chloride is safe as an OTC oral antiseptic when labeled for short-term use (not to exceed 7 days)."^[10]

In addition, the National Library of Medicine Toxicology Data Network (TOXNET) reviewed the range of toxicity of CPC, and stated that, "Significant toxicity is rare after exposure to low concentration products that are typically available in the home."^[11]

The fatal dose in humans ingesting cationic detergents has been estimated to be 1 to 3 g.^[11] Therefore, a person using a typical oral ingestible product that provides 0.25 mg CPC per dose will need to take 4000 doses at one time before they would be in the estimated fatal dose range.

A review of clinical studies on cetylpyridinium chloride found that mouthwashes containing CPC "provide a small but significant additional benefit when compared with toothbrushing only or toothbrushing followed by a placebo rinse" in reducing plaque and gingivitis-inflammation.^[3] In combination with chlorhexidine and zinc lactate, CPC has been found to be effective in treating halitosis.^[12]

Compendial status

• Food Chemicals Codex ^[13]
• United States Pharmacopeia 31 ^[14]
• British Pharmacopoeia 1998 ^[15]

See also

• Mouthwash
• Oral-B
• Chlorhexidine
• Triclosan

Notes

External links

• Material Safety Data Sheet
• Chemical Information
• Sheen, S; Addy, M (2003). "An in vitro evaluation of the availability of cetylpyridinium chloride and chlorhexidine in some commercially available mouthrinse products". British Dental Journal 194 (4): 207–10; discussion 203. doi:10.1038/sj.bdj.4809913. PMID 12627199.