A study with cumulative doses of formoterol and salbutamol in children with asthma.

In a double-blind, cross-over study, 9 children (7-13 yrs old) with stable, moderate asthma inhaled formoterol (6, 18 and 54 micrograms) and salbutamol (100, 300 and 900 micrograms) at hourly intervals, in order to compare the peak effect of cumulative doses of the two drugs. One hour after the last dose, 1 mg salbutamol was inhaled to ensure that maximum bronchodilatation was obtained. The forced expiratory volume in one second (FEV1), peak expiratory flow rate (PEFR), forced vital capacity (FVC), pulse rate, blood pressure and tremor were measured regularly after each dose and the PEFR 5, 7, 9 and 20 h after the last dose. The first dose of each drug improved the FEV1, PEFR and FVC substantially while the following doses only gave minor improvement. The final addition of 1 mg salbutamol produced no further improvement. No statistically significant difference in bronchodilating effect was seen between the two drugs at any point in time. Side-effects were minimal. Our data indicate that doses of 6-24 micrograms formoterol can be recommended for school children. For most patients with mild to moderate bronchial asthma higher doses will not add much to the bronchodilating effect.