Aerosolized Beta-Agonist Isomers in Asthma

Dr. MacIntyre and his colleagues are studying inhaled medications in asthma. There are two new medications that have been approved by the United States Food and Drug Administration (FDA): levalbuterol and formoterol. Both of these drugs are similar to standard asthma bronchodilator drugs but offer theoretical advantages in terms of fewer side effects. There are also newer devices to deliver these medications into the lungs: breath actuated nebulizers (BANs) and non-static chambers (Aerochamber-max) that can be used with metered dose inhalers (MDIs or "puffers"). The purpose of this study is to deliver these new medications using several different devices and measuring lung function, heart rate, and sensations of breathlessness.

Patients will be studied on five separate mornings. The duration of the study and frequency of the visits will be solely dependant on the subject availability. Each subject will receive all 5 treatments in the same order.

Tremor assessment will be made on outstretched hands (0 = none, 1+ = fine tremor, barely perceptible, 2+ = obvious tremor).

Change in Dyspnea Response as Measured by the University of California, San Diego (UCSD) Dyspnea Scale

Inclusion Criteria: stable mild to moderate persistent asthma as defined by the National Asthma Education and Prevention Program greater than 18 years of age requiring bronchodilator therapy either routinely or on a as needed (PRN)basis stable with respect to respiratory disease and at least four weeks removed from the most recent acute exacerbation of the disease patients may or may not be on inhaled corticosteroids Exclusion Criteria: no unstable cardiovascular symptoms no unstable angina must be at least four weeks removed from an acute coronary syndrome