title: Intranasal delivery--modification of drug metabolism and brain disposition.
abstract: Intranasal route continues to be one of the main focuses of drug delivery research. Although it is generally perceived that the nasal route could avoid the first-pass metabolism in liver and gastrointestinal tract, the role of metabolic conversions in systemic and brain-targeted deliveries of the parent compounds and their metabolites should not be underestimated. In this commentary, metabolite formations after intranasal and other routes of administration are compared. Also, the disposition of metabolites in plasma and brain after nasal administrations of parent drugs, prodrugs and preformed metabolites will be discussed. The importance and implications of metabolism for future nasal drug development are highlighted.
authors.affiliation: School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Room 610, Basic Medical Sciences Building, Shatin, New Territories, Hong Kong.
authors.forename: Yin Cheong
authors.initials: YC
authors.lastname: Wong
authors.forename: Zhong
authors.initials: Z
authors.lastname: Zuo
mesh_terms: D000281:Administration, Intranasal; D001921:Brain / Q000378:metabolism*; D016503:Drug Delivery Systems; D006801:Humans; D009296:Nasal Cavity / Q000378:metabolism*