Pharmaceutical excipients - quality, regulatory and biopharmaceutical considerations.

Practically all medications contain excipients, which are added for the purpose of production enhancement, patient acceptability, improving stability, controlling release etc. Typically excipients are the major components of a drug product, with the active molecule only present in relatively small amounts. Historically, excipients were termed inactive components. However, as highlighted in the present paper; excipients can have an impact on the absorption, distribution, metabolism and elimination (ADME) processes of the co-administered drug, which is important information when selecting excipients for any new formulation. Further, this review also provides a description of the regulatory processes to get new excipients approved in different regions and a discussion of the recent regulatory initiatives, e.g. excipients for paediatric formulations, thereby providing points to consider for the pharmaceutical scientist when selecting excipients for a new drug formulation.