A comparison of the duration of action of fenoterol and salbutamol in asthma.

Nine asthmatic subjects were given fenoterol or salbutamol aerosol in a double-blind, placebo controlled, crossover study to compare the duration of action of these two drugs. The dose of each drug used was determined in a separate study in 2 asthmatics when 400 micrograms of each drug by aerosol was found to produce the same degree of bronchodilatation. Both drugs produced significant bronchodilator response compared to placebo but, in the doses used, namely, salbutamol 4 puffs (equivalent to 1.6 mumol free base) fenoterol 2 puffs (equivalent to 1.0 mumol free base), only salbutamol showed a significant increase in FEV1 at 8 hours. There were no significant side-effects, or changes in pulse and blood pressure with either drug.