title: Challenges in nasal drug absorption: how far have we come?
abstract: The nasal route is commonly used for local delivery of drugs to treat inflammatory conditions. It is also an attractive route for systemic delivery of some drugs. Irrespective of intended use, administered drugs must permeate the epithelial or olfactory membrane to be effective. The enthusiasm for potential use of the nasal route for systemic drug delivery has not been met by comparable success. In this paper, the anatomical and physiological attributes of the nasal cavity and paranasal sinuses important for drug delivery and challenges limiting drug absorption are discussed. Efforts made so far in improving nasal drug absorption such as overcoming restrictive nasal geometry and paranasal sinuses accessibility, mucociliary clearance, absorption barriers, metabolism and drug physicochemical challenges are discussed. Highlights on future prospects of nasal drug delivery/absorption were discussed.
authors.affiliation: Biopharmaceutics & Drug Delivery Lab, College of Pharmacy, 5968 College Street, PO Box 15000, Halifax, NS B3H 4R2, Canada.
authors.forename: Remigius U
authors.initials: RU
authors.lastname: Agu
mesh_terms: D000281:Administration, Intranasal; D016503:Drug Delivery Systems; D006801:Humans; D009079:Mucociliary Clearance; D004364:Pharmaceutical Preparations
chemical_list: D004364:Pharmaceutical Preparations
keywords: drug transport; nasal drug absorption; nasal epithelium; olfactory epithelium; sinusitis