Oral controlled release systems: Current strategies and challenges

Abstract

Oral drug delivery route is the widely favored and adaptable for all as it is endowed with a maximum surface area when compared to the other routes of drug administration. The conventional dosage form leads to a wide range of fluctuations in plasma drug concentration with subsequent unwanted toxicity and poor efficiency. Maintaining a steady concentration of the drug in the plasma within the therapeutic index is critical for efficient treatment. By optimizing the biopharmaceutic, pharmacokinetic, and pharmacodynamic properties of drugs, improvement in conventional formulation can be achieved. The reduction of dosing frequency is an extent that single daily dose is enough for the management of uniform plasma concentration to achieve the maximum utility of a drug. Controlled release formulation acts on several mechanisms such as osmotic pressure, matrix system, reservoir system, and altered density system to control the drug release rate. This chapter summarizes the formulation designing approaches, release kinetics, strategies, technologies, recent advancements, and challenges in the development of oral controlled drug delivery systems.