Abstract

Significance Nasal drug delivery technology of traditional Chinese medicine （TCM） is a new administration method where Chinese herbal medicines are prepared and placed in the nasal cavity in a certain dosage form and absorbed by the nasal mucosa to exert local or systemic therapeutic effects. Compared to traditional dosage forms such as injections or oral preparations， nasal drug delivery has the advantages of convenient administration， good targeting， high safety， and fast absorption. It is particularly effective for the treatment of upper respiratory tract infection and other diseases. Therefore， this technology has been widely used in recent years and has become a hot spot in the research and development of new TCM drug delivery systems.

Progress Various nasal dosage forms of TCM have been developed， including nasal drops， lotions， emulsions， aerosols，sprays， powder sprays， sniffing agents， gels， and films. Among them， nasal drops are easy to prepare and cost-effective， but have some shortcomings such as inaccurate dosage， uneven distribution， and easy loss in the nasal cavity. Powder sprays，which do not require propellants and pressure devices， are environmentally friendly， more stable， and have sustained and controlled release. However， they may not deliver the drug effectively to nasal cavity due to varying particle sizes. Aerosols and sprays distribute evenly， are not easily lost， and can achieve bioavailability of 70%~80%. However， they require special injection valve systems and specific containers， which are costly to manufacture and contain propellants that may cause mucosal irritation. Gels， films， and microemulsions can extend the residence time of the drug in the nasal mucosa， improving bioavailability and reducing the administration frequency while increasing drug loading. However， their preparation processes are complex，and their efficacy is unstable. The paper reviews the characteristics and applications of TCM nasal dosage forms， including nasal drops， aerosols， powders， gels， film agents， microemulsions， introduces the theoretical basis， and summarizes the research progress in pharmacology， pharmacokinetics， quality control， irritant studies， and device development.

Conclusions and Prospects Current TCM nasal drug delivery systems face several challenges：1） Most of the TCM nasal administrations involve strong odor and irritating drugs， which can easily cause nasal allergies or injuries. 2） TCM nasal administration mainly focuses on symptom relief， causing diseases prone to relapse. 3） The preparation of TCM nasal formulations is simple，with low drug utilization， typically involving direct grinding or decoction. 4） Absorption enhancers used in clinical studies are often toxic， and may cause greater irritation to the nasal mucosa. They have a greater impact on nasal cilia function and lead to adverse reactions in patients. To address these issues， specific drug and prescription analysis are needed. It is necessary to optimize prescription drugs， select appropriate excipients such as absorption enhancers， and develop effective drug delivery devices. Future studies should emphasize both basic and applied research in TCM nasal drug delivery systems， focusing on pharmacology and pharmacokinetics， quality control methods， and toxic side effects. In addition， new technologies， processes， and methods should be developed to leverage the potential of TCM nasal drug delivery technologies.

Keywords：traditional Chinese medicine；nasal administration technology； quality control