Cetostearyl alcohol

• BPCetostearyl Alcohol
• Ph. Eur.Cetostearyl Alcohol
• USP–NFCetostearyl Alcohol

cetearyl alcohol; alcohol cetylicus et stearylicus; Crodacol CS90; Lanette O; Speziol C16-18; Tego Alkanol 1618

Mixture of solid aliphatic alcohols, mainly octadecan-1-ol (stearyl alcohol) and hexadecan-1-ol (cetyl alcohol) · [67762-27-0]

Polymer, mixture or material of variable composition — no single molecular formula applies.

Semi-solid base, emollient

Typical concentrations: q.s. · Dosage forms: Semi-solid

Used in creams, lotions and ointments as an emollient, a stiffening (consistency-building) agent and a co-emulsifier that stabilises oil-in-water emulsions together with an ionic or non-ionic surfactant. Typical concentrations are about 2–10%, depending on the consistency required. Combined with sodium lauryl sulfate or sodium cetostearyl sulfate it forms emulsifying cetostearyl alcohol (emulsifying wax). It is also used in suppositories and in some modified-release oral matrices.

A white or pale yellow, waxy, unctuous mass, or white flakes, pellets or granules, with a faint characteristic odour and a bland taste.

Composition

stearyl alcohol not less than 40% and stearyl plus cetyl alcohol not less than 90% (Ph. Eur.)

Melting range

49–56 °C

Hydroxyl value

208–228

Iodine value

not more than 2

Solubility

practically insoluble in water; soluble in ethanol (95%), ether and light petroleum; when melted, miscible with fats and liquid and solid paraffins

Stable under normal storage conditions and does not become rancid. Store in a well-closed container in a cool, dry place.

Incompatible with strong oxidising agents and metal salts.

Produced by catalytic reduction (hydrogenation) of the fatty acids or esters of vegetable oils such as coconut or palm oil, or of animal fats, followed by fractional distillation; synthetic fatty alcohols are also used.

Widely used in topical products and generally regarded as non-toxic and non-irritant. Allergic contact dermatitis has been reported occasionally, mostly in patients with damaged skin such as those with leg ulcers; impurities in the alcohol may contribute.

Observe normal precautions for the quantity handled. Eye protection and gloves are recommended. The molten material can cause burns.

Included in the FDA Inactive Ingredient Database (topical, rectal and vaginal preparations) and in non-parenteral medicines licensed in Europe.

Cetyl alcohol; stearyl alcohol; emulsifying wax; cetostearyl alcohol (type A), emulsifying; cetostearyl alcohol (type B), emulsifying.

In oil-in-water creams cetostearyl alcohol combines with the surfactant in the aqueous phase to form a viscoelastic gel network that gives the cream its body; the ratio of stearyl to cetyl alcohol and the source of the material affect the consistency and long-term stability, so supplier changes should be evaluated.