Pharmacoscintigraphy: a blazing trail for the evaluation of new drugs and delivery systems.

The drug development process is becoming increasingly sophisticated; as a result, the need for rapid and accurate means of predicting the in vivo behavior of drug products continues to grow. Preclinical in vivo evaluations involve the sacrifice of many animals and hence raise ethical issues. Therefore, noninvasive methods for assessing the in vivo behavior of drug products in animals have become an attractive alternative. Gamma scintigraphy is an established radiological-imaging technique that has been used in medical practice for the past several decades. Gamma scintigraphy is also used during clinical evaluations to map the formulation as it traverses the human body in real time. Combining this information with the pharmacokinetic data gives valuable information about the release and absorption mechanisms of drugs from their products. This technique also provides a handy tool for evaluating formulations at the preclinical and clinical stages of development for researchers who work in targeted drug delivery using novel drug carrier systems. The current review explores the use of pharmacoscintigraphy, a science that integrates gamma scintigraphy and conventional pharmacokinetics in the process of drug development.