ABSTRACT
Excipients have not been subjected to extensive safety testing because they have been considered a priori to be biologically inactive, therefore, nontoxic. Many, if not most, excipients used are approved food ingredients, the safety of which has been assured by a documented history of safe use or appropriate animal testing. Some of the excipients are Generally Recognized As Safe (GRAS) food ingredients (see Chapter 3). The excipient is an integral component of the finished drug preparation and, in most countries, is evaluated as part of this preparation. There has been no apparent need to develop specific guidelines for the safety evaluation of excipients, and most developed countries do not have specific guidelines. However, as drug development has become more complex and/or new dosage forms have developed, improved drug bioavailability has became more important. It was noted that the available excipients were often inadequate, new pharmaceutical excipients specifically designed to meet the challenges of delivering new drugs were needed, and these are being developed. The proper safety evaluation of these excipients has now become an integral part of drug safety evaluation.
