The role of gamma-scintigraphy in oral drug delivery

The gastrointestinal tract is usually the preferred site of absorption for most therapeutic agents, as seen from the standpoints of convenience of adm inistration, patient compliance and cost. In recent years there has been a tendency to employ sophisticated systems that enable controlled or timed re lease of a drug, thereby providing a better dosing pattern and greater conv enience to the patient. Although much about the performance of a system can be learned from in vitro release studies using conventional and modified d issolution methods, evaluation in vivo is essential in product development. The non-invasive technique of gamma -scintigraphy has been used to follow the gastrointestinal transit and release characteristics of a variety of ph armaceutical dosage forms. Such studies provide an insight into the fate of the delivery system and its integrity and enable the relationship between in vivo performance and resultant pharmacokinetics to be examined (pharmaco scintigraphy). (C) 2001 Elsevier Science B.V. All rights reserved.