Fenoterol plus ipratropium ('Duovent') aerosol therapy delivered by a tube spacer

A randomized crossover study was carried out in 12 patients with reversible airflow obstruction to investigate the bronchodilator effects of a single metered dose of fenoterol hydrobromide (200 micrograms) plus ipratropium bromide (80 micrograms) delivered by the standard aerosol inhaler or by the inhaler with an extension tube spacer. The results of lung function tests showed that there were significant increases from baseline values in FEV1, FVC and PEFR by 15 minutes using both drug delivery methods, and the improvement in PEFR was maintained for at least 8 hours in 11 of the 12 patients. Although no significant differences in the results was demonstrated between the two methods, which were used correctly by all the participants, it is suggested that the spacer device method would be particularly useful for patients who have difficulty in co-ordinating drug delivery with inhalation.