Antimicrobial safety of a preservative-free nasal multiple-dose drug administration system.

Recent technical developments in metered-dose pumps allow preservative-free nasal drug application with multiple-dose systems, avoiding the cytotoxic and allergic problems of preservatives. The use of the 3K System as a representative of those systems is demonstrated as microbiologically safe and without risk for the user and for the product during shelf life, under challenge up to 24 weeks, as well as under worst-case conditions with heavy bacterial contamination on the outlet surface. Therefore, the authors assess preservative-free pump systems as the new gold standard for mucosal drug application.