Nasal Resistance Observations in Decongestant Spray Trials

Publisher Website
Google Scholar
Abstract
Forty-two patients with common colds entered a randomized, double-blind crossover trial of topical nasal therapy. Four sprays (phenylephrine/thenyldi-amine/benzalkonium, phenylephrine/benzalkonium, thenyldiamine/benzalko-nium, and placebo) were instilled in the right nostril. Nasal flow resistance (Rn) was measured in the treated right nostril (Rnr) and the untreated left passage (Rnl) at baseline, and over 6 hours, by electronic posterior rhinometry; an efficacy ratio was calculated for each spray. Nasal resistance rose in the untreated left nostril and the placebo-treated right nostril; the active sprays induced a drop in Rnr. Analysis of Rnr and covariant analysis of Rnr and Rnl indicated that the changes following the active solutions were statistically more significant than those following placebo, or occurring in the left nostril (p = 0.01 or better). The efficacy ratios for the active sprays did not differ from one another at the 95 per cent confidence interval. Estimates of Rn are sensitive indices of effective nasal therapy. Trials of topical medications allow two control references–a direct placebo observation in a treated nostril, and similar measurements in an untreated nostril (“no-placebo” placebo)–and enhance reliability.

This publication has 4 references indexed in Scilit: