Effect of xylometazoline nasal spray on nasal conductance in subjects with coryza.

The ability of xylometazoline topical spray to reduce nasal congestion was evaluated in 44 normal subjects with coryza due to upper respiratory infection. Rating scales were completed for the subjective response and nasal airway resistance (expressed as nasal conductance, Gn) measured for the objective response over six hours. In 30 subjects, post treatment Gn was compared to the measurement after their colds had subsided. The increase in Gn following xylometazoline was rapid and profound, remaining significantly elevated for the six hour period, and it was greater than the asymptomatic value from 10 minutes to nearly five hours. Other symptoms were not markedly affected by the medication. Subjective scores indicated continued relief after treatment, but the small negative correlation suggested that rating scales were not reliable indices of nasal congestion. No differences were observed in the responses when cigarette smokers were compared with nonsmokers.