Formoterol Turbuhaler (R) for as-needed therapy in patients with mild acute exacerbations of COPD

Worsening of underlying bronchospasm maybe associated with acute exacerbati ons of chronic obstructive pulmonary disease (COPD). As airway obstruction becomes more severe, the therapeutic option is to add a short-acting inhale d beta (2)-agonist as needed to cause rapid relief of bronchospasm. Unfortu nately, however, the most effective dosage may increase above that recommen ded during acute exacerbations. Formoterol (Oxis(R)) Turbuhaler(R) has a ra pid onset of action (within minutes) and demonstrates a maintained effect o n airway function. In this study, we examined the effects of formoterol use d as needed in 20 patients with acute exacerbations of COPD. A dose-respons e curve to inhaled formoterol (9 mug per inhalation) or placebo was constru cted using three separate inhalations, i.e. a total cumulative dose of 27 m ug. Dose increments were given at 20-min intervals, with measurements being made 15 min after each dose. Formoterol, but not placebo, induced a large and significant (P<0.001) dose-dependent increase in forced expiratory volu me in 1 sec (FEV1) [mean differences from baseline=0.1311 after 9 <mu>g for moterol (95% CI: 0.096-0.167)] 0.1811 after 18 mug formoterol (95% CI: 0.14 0-0.2221) and 0.2081 after 27 mug formoterol (95% CI: 0.153-0.2631). Howeve r, 27 mug formoterol did not induce further benefit [0.0271 (95% CI: -0.008 -0.0621); P=0.121] when compared with 18 mug formoterol. Results of this st udy suggest the use of higher than customary dose of formoterol for as-need ed therapy to provide rapid relief of bronchospasm in patients suffering fr om acute exacerbations of partially reversible COPD. (C) 2001 Harcourt Publ ishers Ltd.