Description
Cetylpyridinium is a quaternary ammonium with broad-spectrum antiseptic activities.
1 It is active against
S. mutans,
S. sanguis,
E. coli, Oxford
Staphylococcus, and
C. albicans in media (MICs = 1.25-62.5 μg/ml) and against Oxford
Staphylococcus in pooled human saliva (MICs = 7.8-15.6 μg/ml).
2 Cetylpyridinium slows plaque formation for at least 21 days compared to a deionized water control in a rat incisor plaque model when applied topically at concentrations ranging from 0.025 to 2%.
3 Formulations containing cetylpyridinium have been used as antiseptic agents in the treatment of gingivitis and as antimicrobial agents in raw food processing.
Chemical Properties
Cetylpyridinium chloride (CPC) is a white powder or crystals with a characteristic odor. It is slightly soapy to the touch.
Cetylpyridinium chloride is a quaternary ammonium compound and is the active chemical in some human mouthwashes on the market. It has antiseptic properties and is used in solutions or lozenges for the treatment of minor infections of the mouth and throat. The antimicrobial activity is due to an interaction of basic cetylpyridinium ions with acidic molecules on bacteria, which subsequently inhibits bacterial metabolism by forming weak ionic compounds that interfere with bacterial respiration.
Definition
ChEBI: A pyridinium salt that has N-hexadecylpyridinium as the cation and chloride as the anion. It has antiseptic properties and is used in solutions or lozenges for the treatment of minor infections of the mouth and throat.
Production Methods
Cetylpyridinium chloride is prepared from cetyl chloride by
treatment with pyridine.
Brand name
Ceepryn (Marion Merrell
Dow); Cepacol (Marion Merrell Dow).
Flammability and Explosibility
Nonflammable
Pharmaceutical Applications
Cetylpyridinium chloride is a quaternary ammonium cationic
surfactant, used in pharmaceutical and cosmetic formulations as
an antimicrobial preservative. It is used therapeutically
as an antiseptic agent; used alone or in combination with
other drugs for oral and throat care; used in nonparenteral
formulations licensed in the UK; and used in oral and inhalation
preparations at concentrations of 0.02–1.5 mg.
Mouthwashes containing cetylpyridinium chloride have been
shown to inhibit plaque formation,(1–3) although efficacy is variable
owing to limited published data.
Clinical Use
1-Hexadecylpyridinium chloride is a white powder that isvery soluble in water and alcohol. In this compound, thequaternary nitrogen atom is a member of an aromatic pyridinering.
The cetyl derivative is the most active of a series ofalkylpyridinium compounds. It is used as a general antisepticin concentrations of 1:100 to 1:1,000 for intact skin,1:1,000 for minor lacerations, and 1:2,000 to 1:10,000 forthe irrigation of mucous membranes. Cetylpyridinium chlorideis also available in the form of throat lozenges and amouthwash at a 1:20,000 dilution.
Safety
Cetylpyridinium chloride is used widely in mouthwashes as a
bactericidal antiseptic. It is generally regarded as a relatively
nontoxic material when used at a concentration of 0.05% w/v,
although minor side effects such as mild burning sensations on the
tongue have been reported.
At higher concentrations, cetylpyridinium chloride may damage
the mucous membranes in the mouth. It is harmful when ingested or
inhaled. It can cause eye irritation, and is irritant to the respiratory
system and the skin.
LD50 (rat, IP): 0.006 g/kg
LD50 (rat, IV): 0.03 g/kg
LD50 (rat, oral): 0.2 g/kg
LD50 (rat, SC): 0.25 g/kg
LD50 (mouse, IP): 0.01 g/kg
LD50 (mouse, oral): 0.108 g/kg
LD50 (rabbit, oral): 0.4 g/kg
LD50 (rabbit, IV): 0.036 g/kg
storage
Cetylpyridinium chloride is stable under normal conditions. It
should be stored in well-closed containers.
Incompatibilities
Incompatible with strong oxidizing agents and bases. It is also
incompatible with methylcellulose.
Magnesium stearate suspensions in cetylpyridinium chloride
have been shown to significantly reduce its antimicrobial activity.
This is due to the absorption of cetylpyridinium chloride on
magnesium stearate. The cetylpyridinium chloride ion also
interacts with gelatin, resulting in reduced bioavailability.
Toxics Screening Level
The Initial threshold Screening Level (ITSL) is 1.8 μg/m3 based on annual averaging.
Regulatory Status
Included in nonparenteral formulations licensed in the UK. Included
in the FDA Inactive Ingredients Database, for use in inhalation and
oral preparations. Reported in the EPA TSCA Inventory. It is not
approved for use in Japan. Included in the Canadian List of
Acceptable Non-medicinal Ingredients.
References
[1] Journal of the Chemical Society, 1938, p. 682
[2] Helvetica Chimica Acta, 1938, vol. 21, p. 223,230
[3] Journal of Physical Chemistry, 1990, vol. 94, # 9, p. 3734 - 3739
[4] Chemical Communications, 1996, # 14, p. 1625 - 1626
[5] Patent: WO2016/92499, 2016, A1. Location in patent: Page/Page column 8
