Influence of preservatives and topical steroids on ciliary beat frequency in vitro.

OBJECTIVE To measure the influence of topical steroids and the preservative potassium sorbate on the ciliary beat frequency (CBF) of human nasal mucosa in vitro. DESIGN In vitro study of cultured ciliated cells of human nasal mucosa. METHODS Human nasal mucosa was removed endoscopically and cultured for 10 days. Cell cultures with ciliated cells grown on an object slide were exposed to benzalkonium chloride and topical steroids in an exposure chamber. The CBF was measured with a photometer. RESULTS The preservative potassium sorbate did not influence CBF in different concentrations. The glucocorticoid budesonide spray containing potassium sorbate did not affect CBF at 10% dilution and showed moderate reversible decrease of CBF at 50% dilution. The glucocorticoid sprays fluticasone propionate and mometasone fuorate containing the preservative benzalkonium chloride caused a reversible decrease of CBF at 10% dilution and a complete irreversible standstill at 50% dilution. CONCLUSIONS In vitro, the steroid sprays containing fluticasone or mometasone, both with benzalkonium chloride, caused slowing or standstill of CBF depending on the concentration. The isolated preservative potassium sorbate and the budesonide nasal spray containing this preservative did not have negative influence on CBF in vitro. Potassium sorbate can therefore be considered harmless to the motility of ciliated cells.