Human Factors and Device Engineering in OTC Intranasal Drug Delivery: GentleMist Technology™.

Intranasal drug delivery is noninvasive, rapid-acting, and well suited to self-administration, yet the real-world performance of nasal sprays depends on the interaction among formulation, device mechanics, nasal anatomy, and user technique rather than on the active ingredient alone. This narrative review examines how aerosol science, regional targeting, and human factors jointly shape intranasal performance, using GentleMist Technology™ as a representative example of emerging device-centered development. Computational fluid dynamics (CFD) and anatomically informed in vitro models indicate that device geometry, plume characteristics, and administration angle can significantly alter where a dose is deposited, while human factors research identifies priming, positioning, and angulation as key determinants of successful over-the-counter (OTC) use. We summarize early feasibility data suggesting that angle-optimized administration may increase posterior nasopharyngeal delivery and that essential tasks are feasible for lay users, with priming emerging as a specific usability vulnerability. We also review preliminary clinical evidence on a chlorpheniramine maleate (CPM)-based intranasal formulation in allergic rhinitis and viral upper respiratory illness. Although the strongest device-specific findings remain preliminary and require independent replication, they support an emerging shift from a formulation-centered model toward an integrated device-formulation-user paradigm.