Patterns of response to isoprenaline in asthmatic patients

Six asthmatic patients whose airway obstruction improved significantly during a trial of prednisone have been studied in detail. Serial measurements of forced expiratory volume in 1 second (FEV1) were made at specific times each day before and after isoprenaline, for 8 days. Peak response was at 5 minutes in the majority of tests. In contrast to previous studies no clear pattern of response emerged in relation either to type of asthma, length of history or initial FEV1.