Cetyl alcohol is extensively utilized in cosmetics and pharmaceutical products, including suppositories, modified-release solid dosage forms, emulsions, lotions, creams, and ointments.

In suppositories, cetyl alcohol is utilized to increase the melting point of the base. In modified-release dosage forms, it can be used to create a permeable barrier coating. In lotions, creams, and ointments, cetyl alcohol is valued for its emollient, water-absorptive, and emulsifying properties. It enhances stability, improves texture, and increases consistency. The emollient properties stem from the absorption and retention of cetyl alcohol in the epidermis, where it lubricates and softens the skin, giving it a characteristic ‘velvety’ texture.

Cetyl alcohol is also utilized for its water absorption properties in water-in-oil emulsions. For instance, a mixture of petrolatum and cetyl alcohol (19:1) can absorb 40-50% of its weight in water. Cetyl alcohol functions as a mild emulsifier for water-in-oil emulsions, which allows for a reduction in the amount of other emulsifying agents needed in a formulation. Additionally, cetyl alcohol has been noted to enhance the consistency of water-in-oil emulsions.

In oil-in-water emulsions, cetyl alcohol is known to enhance stability by interacting with the water-soluble emulsifying agent. This combination creates a tightly packed, monomolecular barrier at the oil-water interface, which acts as a mechanical barrier to prevent droplet coalescence.

In semisolid emulsions, excess cetyl alcohol interacts with the aqueous emulsifier solution to create a viscoelastic continuous phase. This phase imparts semisolid properties to the emulsion and prevents droplet coalescence. Consequently, cetyl alcohol is often called a ‘consistency improver’ or ‘bodying agent.’ However, it may be necessary to combine cetyl alcohol with a hydrophilic emulsifier to achieve this effect.

It is important to note that pure or pharmacopeial grades of cetyl alcohol may not form stable semisolid emulsions and may lack the same physical properties as grades of cetyl alcohol that contain significant amounts of other similar alcohols.