The effect of sequential inhalations of metaproterenol aerosol in asthma.

In 19 asthmatic patients, three inhalations of metaproterenol (0.65 mg per puff) followed by placebo at 10 and 20 min were compared with one inhalation of the drug every 10 min for the same total of three doses. Metaproterenol 0.65 mg produced just as much increase of 1-sec forced expiratory volume (FEV1) as did the much larger dose (1.95 mg), but each subsequent inhalation of the drug produced further, significant increase of FEV1 suggesting better penetration of the bronchidilator aerosol after some bronchodilation had been achieved. After completion of treatment, the FEV1 was significantly higher when the drug was given sequentially rather than all at once. These data have important implications with respect to the utilization of bronchodilator aerosols in the treatment of asthma and indicate the unsuitability of sequential inhalation for study of dose response of these agents.

RCT Entities:   Population Interventions Outcomes