Functional Category
Emollient; humectant; viscosity increasing agent.
Applications in Pharmaceutical Formulation
Cyclomethicone is mainly used in topical pharmaceutical and cosmetic formulations such as water-in-oil creams.(1–3) Cyclomethicone has been used in cosmetic formulations, at concentrations of 0.1–50%, since the late 1970s and is now the most widely used silicone in the cosmetics industry. Its high volatility, and mild solvent properties, make it ideal for use in topical formulations because its low heat of vaporization means that when applied to skin it has a ‘dry’ feel. See also Dimethicone.
Description
Cyclomethicone occurs as a clear, colorless and tasteless volatile liquid.
Stability and Storage Conditions
Cyclomethicone should be stored in an airtight container in a cool, dry, place.
Safety
Cyclomethicone is generally regarded as a relatively nontoxic and nonirritant material. Although it has been used in oral pharmaceutical applications, cyclomethicone is mainly used in topical pharmaceutical formulations. It is also widely used in cosmetics.(4) Studies of the animal and human toxicology of cyclomethicone suggest that it is nonirritant and not absorbed through the skin. Only small amounts are absorbed orally; an acute oral dose in rats produced no deaths.(5,6) See also Dimethicone.