Influence of the nasal mucociliary system on intranasal drug administration

Objective To study the influence of the nasal mucociliary system on intranasal drug administration and ways of reducing its influence on nasal absorption. Methods Rabbit nasopharynx was closed to stop mucociliary function in one group.In the other group, rabbits maintained their mucociliary function.Both groups were given a nasal drip of gentamycin and the serum levels were measured from 0 to 180 minutes after drug administration.To reduce the undesirable effects of the nasal mucociliary system, acetylcysteine was mixed into the gentamycin drops. In addition, nasal nebulization was evaluated in human volunteers as a means of increasing absorption of the drug in the non-ciliary area of the nasal cavity. Results Nasal mucociliary function reduced intranasal absorption of drug and made the highest absorbing rate and area under the curve (AUC) decrease by 25.1% and 18.2%, respectively.Both the nasal drip containing acetylcysteine and the nebulizer could promote drug absorption in the nasal mucosa.The former made the highest intranasal absorption and AUC increase by 18.0% and 10.7%, respectively.The latter made the absorption increase 1.5-1.6 times. Conclusion The mucociliary system can decrease intranasal drug absorption.Application of acetylcysteine or the use of nebulizer can increase drug absorption.