Effect of pseudoephedrine on nasal airflow in patients with nasal congestion associated with common cold.

The aim of this study was to investigate the efficacy of pseudoephedrine as a nasal decongestant. Patients with nasal congestion associated with common cold received two doses of medication separated by 4 hours, either 60 mg pseudoephedrine (n = 20), or placebo (n = 20). Unilateral nasal airflow was measured over a 7-hour period to record the spontaneous changes in nasal airflow associated with the nasal cycle. Minimum (F MIN) and maximum (F MAX) unilateral nasal airflows were defined as the minimum and maximum nasal airflow values for each nasal passage recorded during the 7-hour period of the study. There was no significant difference in F MAX between the two treatment groups yet there was a significant difference in F MIN (p < 0.05). No difference in total nasal airflow (TNAF) between treatment groups was found, either before or after treatment (p > 0.05). The results demonstrate that (TNAF) is not as sensitive a measure of decongestion as F MIN. The findings of this study show that pseudoephedrine had no effect on the decongestion phase of the nasal cycle, but did significantly limit the congestion phase. The decongestant action may be explained by the sympathomimetic supplementing the natural sympathetic nervous activity to the nasal blood vessels.