Excipients / inactive ingredients are an integral part of practically all medicines. Although being a functional part of a formulation, excipients have been regarded as pharmacologically and chemically indifferent within the formulation.
However, nowadays excipients along with active pharmaceutical ingredients are the subject of strict monitoring and quality control in pharmaceutical manufacture. According to the current rules of European Union’s Good Manufacturing Practice of Medicinal Products excipients should be subjected to a thorough assessment of the risks associated with their quality, safety and function and classified e.g. as low risk, medium risk or high risk. Thus, in the present article available data on excipient function and functionality is considered, on the basis of which possible approaches for the risk assessment related to the excipient function are proposed. These approaches are presented in the form of schematic algorithms and concern such aspects as dosage form and use of the medicinal product containing the excipient, functional purpose, daily patient intake and functional variability of the excipient.