Comparative study of duration of action and cardiovascular effects of bronchodilator aerosols.

The durations of action and side effects of four different pressurized bronchodilator aerosols were compared. One of the preparations contained isoprenaline alone, which was given in a dose of 400 μg. The doses of the three other preparations were adjusted to yield nearly the same peak bronchodilator response as was obtained from 400 μg isoprenaline. These doses differed from those yielded by a single discharge of the standard commercial product. The duration of action of orciprenaline was greater than those of the other preparations. There were no cardiovascular side effects from any of the four preparations. An attempt has been made to establish the principle that drugs whose primary action is similar should be given in equipotential doses when comparing duration of action and side effects.