Name: Cetrimide
CAS No: Cetrimide [8044-71-1]
BP: Cetrimide PhEur: Cetrimide
Bromat; Cetab; Cetavlon; Cetraol; cetrimidum; Lissolamine V; Micol; Morpan CHSA; Morphans; Quammonium; Sucticide.
Cetrimide [8044-71-1]
Cetrimide consists mainly of trimethyltetradecylammonium bromide (C17H38BrN), and may contain smaller amounts of dodecyltrimethylammonium bromide (C15H34BrN) and hexadecyltrimethylammonium bromide (C19H42BrN). C17H38BrN 336.40
Cetrimide is a quaternary ammonium compound that is used in cosmetics and pharmaceutical formulations as an antimicrobial preservative; see Section 10. It may also be used as a cationic surfactant. In eye-drops, it is used as a preservative at a concentration of 0.005% w/v. Therapeutically, cetrimide is used in relatively high concentrations, generally as 0.1–1.0% w/v aqueous solutions, cream or spray as a topical antiseptic for skin, burns, and wounds.(1) Solutions containing up to 10% w/v cetrimide are used as shampoos to remove the scales in seborrheic dermatitis. Cetrimide is also used as a cleanser and disinfectant for hard contact lenses, although it should not be used on soft lenses; as an ingredient of cetrimide emulsifying wax, and in o/w creams (e.g. cetrimide cream).
Cetrimide is a white to creamy white, free-flowing powder, with a faint but characteristic odor and a bitter, soapy taste.
See Table I.
Acidity/alkalinity pH = 5.0–7.5 (1% w/v aqueous solution) Antimicrobial activity Cetrimide has good bactericidal activity against Gram-positive species but is less active against Gramnegative species. Pseudomonas species, particularly Pseudomonas aeruginosa, may exhibit resistance. Cetrimide is most effective at neutral or slightly alkaline pH values, with activity appreciably reduced in acidic media and in the presence of organic matter. The activity of cetrimide is enhanced in the presence of alcohols. The activity of cetrimide against resistant strains of Pseudomonas aeruginosa, Aspergillus niger, and Candida albicans is significantly increased by the addition of edetic acid.(2) Cetrimide has variable antifungal activity,(3,4) is effective against some viruses, and is inactive against bacterial spores. Typical minimum inhibitory concentrations (MICs) are shown in Table II. Critical micelle concentration 3.08 mmol/kg(10) (in water) Melting point 232–2478C Moisture content At 40–50% relative humidity and 208C, cetrimide absorbs sufficient moisture to cause caking and retard flow properties. NIR spectra see Figure 1. Partition coefficients Liquid paraffin : water = <1; Vegetable oil : water = <1. Solubility Freely soluble in chloroform, ethanol (95%), and water; practically insoluble in ether. A 2% w/v aqueous solution foams strongly on shaking.
Cetrimide is chemically stable in the dry state, and also in aqueous solution at ambient temperatures. Aqueous solutions may be sterilized by autoclaving. Water containing metal ions and organic matter may reduce the antimicrobial activity of cetrimide. The bulk material should be stored in a well-closed container in a cool, dry place
Incompatible with soaps, anionic surfactants, high concentrations of nonionic surfactants, bentonite, iodine, phenylmercuric nitrate, alkali hydroxides, and acid dyes. Aqueous solutions react with metals
Cetrimide is prepared by the condensation of suitable alkyl bromides and trimethylamine.
Most adverse effects reported relate to the therapeutic use of cetrimide. If ingested orally, cetrimide and other quaternary ammonium compounds can cause nausea, vomiting, muscle paralysis, CNS depression, and hypotension; concentrated solutions may cause esophageal damage and necrosis. The fatal oral human dose is estimated to be 1.0–3.0 g.(11) At the concentrations used topically, solutions do not generally cause irritation, although concentrated solutions have occasionally been reported to cause burns. Cases of hypersensitivity have been reported following repeated application.(12,13) Adverse effects that have been reported following irrigation of hydatid cysts with cetrimide solution include chemical peritonitis,(14) methemoglobinemia with cyanosis,(15) and metabolic disorders.(1
Observe normal precautions appropriate to the circumstances and quantity of material handled. Cetrimide powder and concentrated cetrimide solutions are irritant; avoid inhalation, ingestion, and skin and eye contact. Eye protection, gloves, and a respirator are recommended.(17)
Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients. Cetrimide is on the list of ‘Existing Active Substances’ on the market in the Europe, and is registered according to REACH regulation. Cetrimide is not present in any approved product in the USA
Benzalkonium chloride; benzethonium chloride; dodecyltrimethylammonium bromide; hexadecyltrimethylammonium bromide; trimethyltetradecylammonium bromide. Dodecyltrimethylammonium bromide Empirical formula C15H34BrN Molecular weight 308.35 CAS number [1119-94-4] Synonyms DTAB; N-lauryl-N,N,N-trimethylammonium bromide; N,N,N-trimethyldodecylammonium bromide. Safety LD50 (mouse, IV): 5.2 mg/kg(18) LD50 (rat, IV): 6.8 mg/kg Hexadecyltrimethylammonium bromide Empirical formula C19H42BrN Molecular weight 364.48 CAS number [57-09-0] Synonyms Cetrimide BP 1953; cetrimonium bromide; cetyltrimethylammonium bromide; CTAB; N,N,N-trimethylhexadecylammonium bromide. Appearance A white to creamy-white, voluminous, free-flowing powder, with a characteristic faint odor and bitter, soapy taste. Melting point 237–2438C Safety LD50 (guinea pig, SC): 100 mg/kg(19) LD50 (mouse, IP): 106 mg/kg LD50 (mouse, IV): 32 mg/kg LD50 (rabbit, IP): 125 mg/kg LD50 (rabbit, SC): 125 mg/kg LD50 (rat, IV): 44 mg/kg LD50 (rat, oral): 410 mg/kg Solubility Freely soluble in ethanol (95%); soluble 1 in 10 parts of water. Comments The original cetrimide BP 1953 consisted largely of hexadecyltrimethylammonium bromide, with smaller amounts of analogous alkyltrimethylammonium bromides. It contained a considerable proportion of inorganic salts, chiefly sodium bromide, and was less soluble than the present product. Trimethyltetradecylammonium bromide Empirical formula C17H38BrN Molecular weight 336.40 CAS number [1119-97-7] Synonyms Myristyltrimethylammonium bromide; tetradecyltrimethylammonium bromide; N,N,N-trimethyl-1-tetradecanaminium bromide. Safety LD50 (mouse, IV): 12 mg/kg(20) LD50 (rat, IV): 15 mg/kg
As a precaution against contamination with Pseudomonas species resistant to cetrimide, stock solutions may be further protected by adding at least 7% v/v ethanol or 4% v/v propan-2-ol. The EINECS number for cetrimide is 214-291-9. The PubChem Compound ID (CID) for cetrimide includes 68166 (trimethylhexadecylammonium hydroxide) and 14250 (trimethyltetradecylammonium bromide).