Abstract: Nanotechnology has significantly improved drug delivery and targeting in central nervous system diseases and neurodegenerative diseases. Intranasal drug delivery has emerged as a promising approach for enhancing therapeutic outcomes by leveraging the unique anatomical and physiological characteristics of the nasal cavity. This route offers several advantages, including rapid absorption, bypassing the blood-brain barrier for central nervous system targeting, and improved patient compliance. The highly vascularized nasal mucosa facilitates efficient systemic drug absorption, making it an attractive option for both local and systemic treatments. This article explores the principles of intranasal drug delivery, the influence of nasal anatomy on drug bioavailability, and advancements in formulation strategies to optimize efficacy. Additionally, it addresses current challenges, including mucociliary clearance and enzymatic degradation, as well as innovative solutions designed to enhance drug stability and absorption. Understanding the interplay between nasal anatomy and drug delivery mechanisms can pave the way for novel therapeutic interventions and enhance the effectiveness of intranasal medications in various clinical applications. It also highlights challenges in the nasal delivery of therapeutics.