Functional Category
Coating agent; opacifier; stabilizing agent; stiffening agent
Applications in Pharmaceutical Formulation
Ceresin is used as a stiffening agent in creams and ointments,(1,2) and as an emulsion stabilizer, opacifier, viscosity control agent, and thickener in pharmaceutical protective, topical, and vaginal creams.(3) It is also used in cosmetics and personal care products (see Section 18). Ceresin is often used as a substitute for ozokerite wax due to its similar properties, and also as a substitute for beeswax and paraffin wax. It acts as a rheological modifier at low concentrations (2–3%) and has the ability to create very small crystallites, which crosslink and establish a network structure that does not allow flow in practical conditions.(4) Ceresin produces stable mixtures with oils and prevents bleeding or sweating of oil, and it produces a lighter cream that is less greasy. Ceresin is also used for pharmaceutical coating applications of medicaments, for example, protective coatings,(5) enteric coatings,(6) and sustained-release coatings.(7) It has been used in the formulation of multivesicular emulsion topical delivery systems.(8)
Description
Ceresin is a white-to-yellow waxy mixture of hydrocarbons obtained by purification of ozokerite. It occurs as odorless, tasteless, amorphous (noncrystalline) brittle, waxy cakes or pastilles.
Stability and Storage Conditions
Ceresin should be stored in well-closed containers in a cool, dry, well-ventilated place, away from extreme heat and strong oxidizing agents.
Incompatibilities
Incompatible with strong oxidizing agents and metal salts.
Safety
Cetostearyl alcohol is mainly used in topical pharmaceutical formulations and topical cosmetic formulations. 3.0 1215 1392 1730 1764 2012 1779 1749 2297 2325 2340 2364 2442 2352 2312 0.0 1000 −5.0 × [2nd deriv. log(1/R)] 1100 1300 1500 1700 1900 2100 2300 2500 Wavelength/nm −0.2 0.7 log(1/R) Figure 1: Near-infrared spectrum of cetostearyl alcohol measured by reflectance. C 150 Cetostearyl alcohol is generally regarded as a nontoxic material.(22) Although it is essentially nonirritating, sensitization reactions to cetostearyl, cetyl, and stearyl alcohols(23–28) have been reported. Gamma radiation has been shown to be feasible for sterilization of petrolatum containing cetostearyl alcohol resulting in low levels of radiolysis products, which are of low toxicity.(29