Intravenous admixture compounding is common practice in most hospitals throughout the world, regardless of the country. Compounding intravenous medications involves risk, as there is a high potential for error due to their complexity in compounding as well as the additional issues that working in an aseptic compounding environment poses for the compounder. This article in a series of intravenous admixture compounding discusses considerations involved when using commercial products in compounding, as well as a discussion on the issues of freezing, solubility, sorption, leaching, incompatibilities, and quality control, with an emphasis on physicochemical considerations.