Formoterol Turbuhaler® for as-needed therapy in patients with mild acute exacerbations of COPD

Worsening of underlying bronchospasm maybe associated with acute exacerbations of chronic obstructive pulmonary disease (COPD). As airway obstruction becomes more severe, the therapeutic option is to add a short-acting inhaled beta (2)-agonist as needed to cause rapid relief of bronchospasm. Unfortunately, however, the most effective dosage may increase above that recommended during acute exacerbations. Formoterol (Oxis(R)) Turbuhaler(R) has a rapid onset of action (within minutes) and demonstrates a maintained effect on airway function. In this study, we examined the effects of formoterol used as needed in 20 patients with acute exacerbations of COPD. A dose-response curve to inhaled formoterol (9 mug per inhalation) or placebo was constructed using three separate inhalations, i.e. a total cumulative dose of 27 mug. 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 volume in 1 sec (FEV1) [mean differences from baseline=0.1311 after 9 <mu>g formoterol (95% CI: 0.096-0.167)] 0.1811 after 18 mug formoterol (95% CI: 0.140-0.2221) and 0.2081 after 27 mug formoterol (95% CI: 0.153-0.2631). However, 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 study suggest the use of higher than customary dose of formoterol for as-needed therapy to provide rapid relief of bronchospasm in patients suffering from acute exacerbations of partially reversible COPD. (C) 2001 Harcourt Publishers Ltd.