title: Reversion of methacholine induced bronchoconstriction with inhaled diazepam in patients with asthma.
abstract: BACKGROUND
  Benzodiazepines have a direct bronchodilatory effect. Methacholine is a non-selective muscarinic receptor agonist causing bronchoconstriction.
  
  
  OBJECTIVE
  To examine the effects of inhaled benzodiazepines, modulating bronchoconstriction induced by methacholine in patients with asthma.
  
  
  METHODS
  Twelve patients with well controlled asthma were studied. On the first day, after determining the initial values of pulmonary function, a dose response curve was carried out with progressive doses of methacholine. After the last dose, when at least a 20% drop of the initial forced expiratory volume in the first second (FEV1) was achieved, vital capacity (VC) and FEV1 were measured at 7, 15 and 30 minutes after provocation. On the second day a diazepam aerosol was inhaled by the patients prior to the same protocol with methacholine.
  
  
  RESULTS
  In the first day of testing, methacholine inhalation (6 mg/mL) led to a significant drop in FEV1 from 2.98 to 1.69 L. On the second day of study, in the same patients, previous inhalation with diazepam reduced the changes of FEV1 after inhalation of methacholine. This parameter decreased from 2.48 to 2.21 L.
  
  
  CONCLUSIONS
  Inhalation of benzodiazepines reduce bronchoconstriction after a methacholine challenge in patients with asthma.
authors.forename: Mirjana
authors.initials: M
authors.lastname: Miric
authors.forename: Sinisa
authors.initials: S
authors.lastname: Ristic
authors.forename: Bojan N
authors.initials: BN
authors.lastname: Joksimovic
authors.forename: Snezana
authors.initials: S
authors.lastname: Medenica
authors.forename: Maja
authors.initials: M
authors.lastname: Racic
authors.forename: Slavica
authors.initials: S
authors.lastname: Ristic
authors.forename: Vedrana R
authors.initials: VR
authors.lastname: Joksimovic
authors.forename: Mirjana
authors.initials: M
authors.lastname: Skipina
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000886:Anthropometry; D001249:Asthma / Q000503:physiopathology / Q000517:prevention & control*; D001569:Benzodiazepines / Q000627:therapeutic use; D001985:Bronchial Provocation Tests / Q000379:methods; D016084:Bronchoconstriction / Q000187:drug effects*; D016085:Bronchoconstrictor Agents / Q000037:antagonists & inhibitors*; D003975:Diazepam / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008297:Male; D016210:Methacholine Chloride / Q000037:antagonists & inhibitors*; D008875:Middle Aged; D011963:Receptors, GABA-A / Q000627:therapeutic use*; D012016:Reference Values; D015203:Reproducibility of Results; D013997:Time Factors; D014797:Vital Capacity / Q000502:physiology
chemical_list: D016085:Bronchoconstrictor Agents; D011963:Receptors, GABA-A; D016210:Methacholine Chloride; D001569:Benzodiazepines; D003975:Diazepam