Bronchodilating effects of cumulative doses of formoterol from a novel multi-dose inhaler (Airmax)

The bronchodilating properties of formoterol from a novel multi-dose inhaler, Airmax 6 microg and from a single-dose dry powder inhaler Foradil Aeroliser 12 microg were investigated in 31 adult asthmatics with FEV1 > or = 60% predicted and a reversibility > or = 12%. Patients received on a single day four doses of formoterol: cumulative dose 6, 12, 24 and 48 microg from Airmax, or 12, 24, 48 and 96 microg from Aeroliser. The mean FEV1 (SD) from baseline to 1 h after the final cumulative dose increased by 0.81 l from 2.62 (0.58) to 3.43 l (0.70) with Airmax and by 0.85 l from 2.65 (0.60) to 3.5 l (0.68) with Aeroliser. All 90% CIs for all four dose comparisons were within the equivalence range +/- 0.11. There was a higher incidence of hypokalaemia and hyperglycaemia at highest doses during treatment with the Aeroliser than with Airmax. In conclusion, formoterol delivered from Airmax provides a dose-dependent bronchodilating effect which is similar to that obtained by Aeroliser, at double the dose.