Abstract
The application of nanotechnology for medical purposes has been defined as nanomedicine and is specifically focused on the use of nanomaterials for diagnosis, imaging, management, prevention, and treatment of diseases. These medical necessities greatly increase a set of opportunities in drug development; however, some concerns about safety issues have emerged. In comparison, the physicochemical and pharmacokinetic properties of the nanoformulation can largely differ with its parent drug molecule, especially in the rates of absorption, distribution, elimination, and metabolism. It is also proven that such miniaturized drug formulations have greater potential to cross biological barriers. Greater concerns are also there about toxic properties of such synthesized nano-formulations and their persistence in the environment and the human body. In this chapter, it is aimed to elucidate the critical challenges faced by the researchers and clinicians during the development and usage of such nano-formulations especially when administered through nonparenteral routes. The topics outlined in this chapter addresses critical concerns regarding the complexity of the nonparental nanomedicines and provide basic information about the pharmaceutical development, its nonclinical, and early clinical studies.