Evaluation of Decongestive Effect of Topical Imidazoline Derivatives and Oral Pseudoephedrine with Acoustic Rhinometry in Healthy Subjects

Abstract

Objectives:To evaluate the decongestive effects of topical imidazoline derivatives and oral pseudoephedrine in healthy subjects and to compare their decongestive potentials by using acoustic rhinometry (AR).Materials and Methods:Seven groups each containing 13 cases were included in this study. Each group was tested with one of the 7 test medications [5 different imidazoline derivatives (oxymetazoline 0.05%, indanazoline 1.18 mg/ml, xylometazoline 0.1%, tetrahydrozoline 0.1%, naphazoline 0.5 mg/ml), oral pseudoephedrine (60 mg) and physiologic saline]. AR measurements were conducted just before and 20, 40, 240 and 480 minutes after the administration of test medication [investigation time (IT) 0-4]. Measured total nasal volumes (tVOL) at each IT were compared with each other to evaluate the decongestive effect of each medication and to compare their decongestive potentials.Results:Oral pseudoephedrine showed a decongestive effect only at IT3. All imidazoline derivatives showed significant nasal decongestion at IT1 and IT2. These decongestive effects have continued at IT3 for all imidazoline derivatives except indanazoline. No test medication showed nasal decongestion at IT4. Comparison of decongestive effects of medications with physiologic saline showed that a single dose oral pseudoephedrine has no superior decongestive effect than physiologic saline. The most potent decongestive effect was achieved with tetrahydrozoline.Conclusion:As far as AR evaluations are concerned, one single dose of oral pseudoephedrine has no decongestive effect on healthy nasal mucosa. Tetrahydrozoline was found to be most potent nasal decongestant.

Keywords

• nasal decongestion
• acoustic rhinometry
• imidazoline derivatives
• oral pseudoephedrine.