PC20methacholine (mg/ml ) | PD30+methacholine (mg) | Recovery time (min) | |
Formoterol (n=17) | 2.23 (1.6 to 3.1)3-150 | 2.48 (0.38–25.6)3-150 3-159 | 30.6 (21 to 45)3-150 |
Salmeterol (n=16) | 1.59 (1.1 to 2.3)3-150 | 1.58 (0.28–6.4)3-150 | 25.8 (17 to 39)3-150 |
Placebo (n=16) | 0.81 (0.57 to 1.1) | 0.74 (0.08–4.8) | 6.9 (4.5 to 10) |
Values are geometric mean (95% CI) for PC20 and recovery time, and geometric mean (range) for PD30+. Values for recovery time above 60 minutes arbitrarily set at 75 minutes.
PC20 = concentration of methacholine provoking a decrease in FEV1 of 20%; PD30+ = cumulative dose of methacholine provoking a decrease in FEV1 of ⩾30%.
↵3-150 p<0.05 compared with placebo;
↵3-159 p<0.05 compared with salmeterol.