EFFECT OF INHALING HEATED VAPOR ON SYMPTOMS OF THE COMMON COLD

Objective.-To test the efficacy of steam inhalation in treating common cold symptoms. Design.-An in vitro study determined the temperature that inactivated rhinovirus: a temperature of 43-degrees-C lasting at least 1 hour was needed. We then conducted a double-blind, placebo-controlled, randomized in vivo study. Setting.-The virology laboratory and the outpatient department of the Cleveland (Ohio) Clinic Foundation. Patients.-Sixty-eight Cleveland Clinic employee volunteers with symptoms of the common cold at the time of enrollment. Intervention.-A single 60-minute treatment was given to the volunteers. The steam treatment group (n=32) received 40 L/min of heated saturated air that raised the intranasal temperature to 43-degrees-C. The placebo group (n=36) received 2 L/min of ambient air at 20-degrees-C to 24-degrees-C. Main Outcome Measures.-Subjective symptom scores for nasal congestion, nasal drainage, and sneezing and objective measures of nasal resistance were studied during a 7-day follow-up observation period. Results.-There were no significant differences in daily symptom scores between the groups (P=.59 to .83). The only statistically significant differences between the groups were lower nasal resistances at baseline in the steam group (P=.04) and percent improvement in nasal resistance favoring the placebo group on day 7 (P=.01). However, these differences were of questionable clinical significance. Conclusion.-We conclude that steam inhalation treatment had no beneficial effect on the cold symptoms of our volunteers.