title: Acute and short-term effect of an extra dose of formoterol in COPD patients.
abstract: BACKGROUND
  Formoterol action may decrease progressively after its inhalation. It is unknown if this decrease of bronchodilation following formoterol use could be associated with worsening hyperinflation.
  
  
  OBJECTIVE
  To investigate whether the use of an extra daily dose of formoterol could promote a greater reduction in lung hyperinflation and a greater improvement in inspiratory capacity (IC) compared to usual doses.
  
  
  METHODS
  56 hyperinflated COPD patients were divided into two groups: F2 and F3. Basal evaluation was carried out after 5 days of formoterol washout. In order to evaluate the acute effect, spirometry and body plethysmography were performed 8 h after the first formoterol dose in both groups and repeated 1 h after an additional formoterol dose (F3) or placebo (F2). The short-term effect was evaluated by measuring the resting lung function after a 14-day period of formoterol t.i.d. (F3) or formoterol b.i.d. + placebo (F2).
  
  
  RESULTS
  A second formoterol dose inhaled 8 h after the previous dose promoted additional improvements in lung function, as demonstrated by higher IC (118 ± 140 mL, p < 0.001) and lower functional residual capacity (FRC) (-383 ± 367 mL, p < 0.001). On day 15, the mean differences from baseline regarding all lung function variables were similar between the groups.
  
  
  CONCLUSIONS
  An extra daily dose of formoterol inhaled 8 h after a previous dose could result in an acute additional peak of bronchodilation. However, short-term formoterol t.i.d. showed no advantages over formoterol b.i.d. concerning reduction of hyperinflation in resting lung function.
authors.affiliation: Respiratory Division of Federal University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Fernando Sérgio
authors.initials: FS
authors.lastname: Studart
authors.forename: Meyer
authors.initials: M
authors.lastname: Izbicki
authors.forename: Luiz Eduardo
authors.initials: LE
authors.lastname: Nery
authors.forename: Luís Vicente Franco
authors.initials: LV
authors.lastname: Oliveira
authors.forename: Claudio F
authors.initials: CF
authors.lastname: Donner
authors.forename: José Roberto
authors.initials: JR
authors.lastname: Jardim
authors.forename: Oliver Augusto
authors.initials: OA
authors.lastname: Nascimento
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D001993:Bronchodilator Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004983:Ethanolamines / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D005260:Female; D000068759:Formoterol Fumarate; D006801:Humans; D008297:Male; D008875:Middle Aged; D010993:Plethysmography, Whole Body / Q000379:methods; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy* / Q000503:physiopathology; D015656:Respiratory Mechanics / Q000187:drug effects; D013147:Spirometry / Q000379:methods; D016896:Treatment Outcome
chemical_list: D001993:Bronchodilator Agents; D004983:Ethanolamines; D000068759:Formoterol Fumarate