Effect of inhaling heated vapor on symptoms of the common cold
G. J. Forstall, M. L. Macknin, B. R. Yen-Lieberman and S. V. Medendrop
Department of Infectious Disease, Cleveland Clinic Foundation, Ohio 44195.
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.
