Hexoprenaline and terbutaline administered by inhalation. A comparison between two beta2-adrenoreceptor agonists with respect to effect on bronchial obstruction, heart rate, blood pressure and muscle tremor.

In a controlled double-blind cross-over study in 15 patients with reversible bronchial obstruction hexoprenaline (Ipradol, 0.20 mg/puff) and terbutaline (Bricanyl, 0.25 mg/puff) when administered as metered aerosol in a dosage of one puff followed by two puffs 30 min later produced the same maximum improvement of ventilatory function. However, after inhalation of terbutaline a more sustained broncholytic effect was obtained than after hexoprenaline. Similar results were obtained in six patients after doubling the dose of each agent. The influence on pulse rate and blood pressure was negligible with either agent. The amplitude of finger tremor was measured after 2 + 4 puffs. No significant changes in mean values occurred after either of the two agents although after hexoprenaline an increase in amplitude of more than 100% was recorded in two out of six patients 30 min after the second dose.