A new exhalation-assisted aerosol delivery method for nasal administration

Nasal administration can be used to treat not only local and systemic diseases but also central nervous system diseases. However, the delivery efficiency to the target site needs to be improved. In this paper, a new exhalationassisted aerosol delivery method (EDM) for nasal administration is proposed. Numerical simulation model validated by experiments was applied to investigate the transport phenomenon of aerosol drugs in the nasal cavity. The effects of aerosol particle diameter and expiratory flow rate on delivery efficiency were investigated. The results show that exhalation flow prevents small-sized particles from entering the larynx and lower respiratory tract, so it will reduce drug wastage and side effects. Moreover, the delivery efficiency of EDM was compared with bi-direction nasal delivery method (BDM) to confirm that the proposed method has an advantage. A slight exhalation flow during aerosol administration can achieve higher delivery efficiency to the turbinate compared with BDM for small particles. There exists an optimum expiratory flow rate for a specific particle size that maximizes the delivery efficiency of the turbinate. The EDM has the advantages of more uniform drug distribution and higher delivery efficiency, it may be more promising for the treatment of central nervous system diseases, local diseases, and systemic diseases in the future.