The extrapulmonary effects of inhaled hexoprenaline and salbutamol in healthy individuals.

We have investigated the cardiovascular and metabolic effects of multiple inhaled doses of salbutamol and hexoprenaline in 12 healthy volunteers. They inhaled 200 micrograms of salbutamol or hexoprenaline at 15 min intervals for 60 min from a metered dose inhaler (total dose 1000 micrograms). We measured heart rate, blood pressure, total electromechanical systole (as a measure of inotropic response), QTc interval on the ECG, and plasma potassium at baseline, 10 min after each inhalation, and 30 and 60 min after the last inhalation. There was no difference in the effects of the two drugs on blood pressure, total electromechanical systole, or QTc interval. Salbutamol significantly increased heart rate compared with hexoprenaline. Hexoprenaline caused a significantly greater fall in plasma potassium compared with salbutamol.