Pharmaceutical excipients: where do we begin?

Abstract

Excipients have been defined in many ways, including as inert substances used as vehicles and diluents for drugs. The problem with this definition is that in recent years excipients have proved to be anything but inert, not only possessing the ability to react with other ingredients in the formulation, but also to cause adverse and hypersensitivity reaction in patients. These range from a mild rash to a potentially life-threatening reaction. Different brands of the same drug may contain different excipients, especially preservatives and colourants. The Comsumer Medicines Information provides a list of excipients, and information on the safety of individual excipients can be found in drug reference guides.