title: The assessment of the optimal duration of early intervention with montelukast in the treatment of Japanese cedar pollinosis symptoms induced in an artificial exposure chamber.
abstract: OBJECTIVE
  The study objective was to investigate the prophylactic efficacy of montelukast (MLK) 10 mg in suppressing seasonal allergic rhinitis (SAR) symptoms induced by Japanese cedar (JC) pollen and to determine how many days before exposure to JC in the artificial exposure chamber (OHIO chamber) would be optimal to start administration.
  
  
  METHODS
  This was a single-institution, double-blind, randomized placebo-controlled four-group parallel inter-group comparison study. Adult volunteers with JC pollinosis were divided into four groups: an MLK 7-day administration group (n = 27), an MLK 3-day administration group (n = 27), an MLK 1-day administration group (n = 26), and a placebo group (n = 26). The mean change in total nasal symptom scores (nasal obstruction, nasal discharge and sneezing) (TNSS) and each of the nasal symptom scores during exposure of JC pollen in the OHIO chamber were investigated.
  
  
  RESULTS
  The mean change in TNSS was significantly lower in the MLK treatment group, regardless of the number of days of administration, than in the placebo group (p = 0.0192). The results for the individual nasal symptoms showed that nasal obstruction was significantly suppressed in the 1-day administration group as compared with placebo (p = 0.0076), but no differences were found in sneezing score between any of the groups. For nasal discharge, we found a trend towards the effect clearing up after 3 days of administration. No serious adverse events were observed during the study.
  
  
  CONCLUSIONS
  Although this study was acute and this artificial exposure model was conducted out of the pollen season, nasal symptoms that developed in the pollen exposure chamber, especially nasal obstruction, were significantly suppressed by starting oral administration of MLK 10 mg at least 1 day before exposure. These results suggest that prophylactic administration of MLK is effective and safe in the treatment of SAR.
authors.affiliation: Department of Otolaryngology, Futaba Clinic, TokyoJapan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hashiguchi
authors.affiliation: Department of Otolaryngology, Nippon Medical School, TokyoJapan.
authors.forename: Kimihiro
authors.initials: K
authors.lastname: Okubo
authors.affiliation: Department of Otorhinolaryngology, Kitasato Institute Hospital, TokyoJapan.
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Wakabayashi
authors.affiliation: Tanaka ENT Clinic, Tokyo, Japan; Department of Otorhinolaryngology, Tokyo Women's Medical University Medical Center East, TokyoJapan.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Tanaka
authors.affiliation: Department of Otorhinolaryngology, Keio University School of Medicine, TokyoJapan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Watada
authors.affiliation: Pharmaceutical Department, Medical Corporation Shinanokai, Samoncho Clinic, TokyoJapan.
authors.forename: Kiyochika
authors.initials: K
authors.lastname: Suematsu
authors.affiliation: Department of Otolaryngology, Nippon Medical School, TokyoJapan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Gotoh
keywords: Early intervention; Environmental exposure chamber; Japanese cedar pollinosis; Montelukast Clinical Trial Registration: UMIN Clinical Trials Registry number