Evaluating Long Acting Beta Agonists Used to Treat Asthma Among Those With Either Arg/Arg or Gly/Gly Genotypes

The investigators are conducting a study of asthma patients who use fluticasone with salmeterol (Advair) or any other combination of an inhaled corticosteroid (ICS) and a long acting beta agonist (LABA) to manage their asthma symptoms. Participants begin the study by continuing to use fluticasone with salmeterol or substituting fluticasone with salmeterol for their current ICS/LABA medication at their regular dose or the comparable dose(all study medications are provided) for a six-week period. Patients are then separated into 2 groups: one group is asked to use fluticasone (Flovent), the other to use fluticasone with salmeterol , twice daily over a 16-week period (patients will need to be seen monthly during this time). Neither study personnel nor patients will know which drug is being used. Patients are also asked to use a peak flow meter and record their daily results on a form, along with the number of puffs they use of their rescue inhaler each day. They also record any changes in asthma medications and information on any asthma episodes. The investigators hypothesize that there are certain patients with asthma who will do better when a long acting beta agonist is removed from their maintenance asthma medications.