[Clinical pharmacological trials of a new metered dose inhaler, IK-6, a combination of the bronchodilators fenoterol and ipratropium bromide (author's transl)].

IK-6, a combination of the sympathomimetic fenoterol (low dose) and the anticholinergic ipratropium bromide (normal dose), was tested single-blind and cross-over in outpatients with intrinsic asthma and in healthy volunteers. In 12 patients IK-6 resulted in a good acute bronchodilatation, the onset was as quick as following fenoterol and the maximum was as good as following ipratropium bromide. In another 12 patients the protective effect against an acetylcholine-induced bronchoconstriction was better after IK-6 than after ipratropium bromide and much better than after salbutamol. In these patients IK-6 caused no unwanted side effects. In 10 healthy volunteers the effect on heart rate was tested after inhalation of 20 puffs of bronchodilators applied by metered dose inhaler. The anticholinergics (ipratropium bromide, oxitropium bromide, dibenzothiepine-derivative) caused no effect. Following fenoterol a marked increase in heart rate could be observed, whereas the combination IK-6 caused only a slight increase.