Targeted Drug Delivery Systems Mediated Through Nasal Delivery for Improved Absorption: an Update

Abstract

Purpose: This review article focuses on providing updated information about targeting the nasal mucosa for drug delivery. The article would serve as a tool for researchers and students to gain insight into the various aspects of nasal drug delivery. Approach: The anatomy and physiology of the nasal region have been discussed, followed by a discussion of the factors and barriers affecting the drug absorption, strategies to improve the drug absorption, various excipients employed in nasal formulations, different types of nasal formulations and applications of nasal delivery. Findings: The high permeability, high vascularity, very low enzymatic activity, accessible surface area and avoidance of first pass hepatic metabolism are the main factors for which it is being considered as a superior delivery route for many drugs in the recent decades. The effects which are mainly systemic encourage the deployment of this route of administration. This route of drug delivery has been also been exploited for delivering the drugs to the central nervous system bypassing the Blood Brain Barrier (BBB). Different forms of dosage forms such as sprays, powders, gels, solutions are administered through this route. Conclusion: Intranasal delivery of drugs is a promising alternative to other routes of administration because, it is rapid and non-invasive and leads to increased bioavailability of poorly bioavailable drugs. The dose of the drug used is minimal compared to other routes hence the systemic side effects are reduced. Compared to parenteral administration it has better compliance and improved patient acceptability. More fundamental research will lead to better understanding of this route and eventually more marketed products.