Cremophor

Cremophor is a brand name for a family of nonionic surfactants derived from castor oil, consisting of polyethoxylated derivatives used as solubilizers and emulsifiers in pharmaceutical, cosmetic, and food applications. The principal members are Cremophor EL (polyoxyl 35 castor oil) and Cremophor RH40 (polyoxyl 40 hydrogenated castor oil).

In medicine, Cremophor EL in particular has been used to solubilize hydrophobic drugs for intravenous administration, most notably paclitaxel in its traditional solvent-based formulation. Because of safety concerns, alternative Cremophor-free formulations (for example, albumin-bound paclitaxel) have been developed. Cremophor RH40 is also used as a pharmaceutical excipient, but to a lesser extent.

Safety and regulatory considerations: Cremophor EL can trigger hypersensitivity reactions, including anaphylactoid responses during infusion. Reactions may occur despite standard premedication, so slow infusion and vigilant monitoring are recommended. The excipient can also alter drug pharmacokinetics by affecting distribution and clearance and may contribute to infusion-related toxicity.

Beyond medicine, Cremophor is used as an emulsifier in cosmetics and processed foods, where it functions as a surfactant and stabilizer. It is derived from castor oil through ethoxylation and is subject to purity and safety standards to minimize contaminants such as residual solvents or ricin.