Influence of topical phenylpropanolamine on tachyphylaxis and mucociliary clearance in the human nose.

Topical nasal phenylpropanolamine in a 2.5 per cent solution (PPA) was used in an evaluation of the possible development of tachyphylaxis and of possible effects on the mucociliary system after one week of treatment in healthy humans. The tendency of PPA to produce tachyphylaxis was evaluated by rhinomanometrie measurements of nasal airway resistance after repeated dose-response provocations. The mucociliary transport time was tested with the saccharine-dye test. No reduced dose-response effect or change in mucociliary transport time was found with PPA, thus indicating that one week of treatment does not contribute to such adverse effects.