NASAL ROUTE : A NOVELISTIC APPROACH FOR TARGETED DRUG DELIVERY TO CNS

Drug delivery through nasal route has attracted the interest o f scientific community as it has been potentially explored as an alternative route for the administration of vaccines and biomolecules such as proteins, peptides and non - peptide drugs that are susceptible to enzymatic or acidic degradation and first pass h epatic metabolism. The nasal mucosa is one of the most permeable and highly vascularis ed sites for drug administration ensuring rapid absorption and onset of therapeutic action. Intranasal administration is a non - invasive route for drug delivery, which is widely used for the local treatment of rhinitis or nasal polyposis. Since drugs can be absorbed into the systemic circulation through the nasal mucosa, this route may also be used in a range of acute or chronic conditions requiring considerable systemic ex posure. In addition it minimizes the lag time associated with oral drug delivery and offers non - invasiveness, self medication, patient comfort and patient compliance which are hurdled in intravenous drug therapy. The objective of this revie w is to provide an anatomical, histological and physiological overview of nose, absorption enhancers, barriers related to nasal drug delivery, physicochemic al, biological and formulation related factors affecting nasal drug delivery system and its advantages. It also high lights research approaches on brain targeting through nasal cavity.