 This is an open-label, multicenter, TMAI study with Levalbuterol HFA MDI in adult and pediatric subjects with asthma or COPD. Period I: One week, open-label, run-in period during which subjects must have asthma or COPD symptoms requiring use of, as needed, Levalbuterol HFA MDIwithout TMAI on at least half of the days 4-12 actuations on a single day. Period II: Nine week, open-label period during which subjects will use the Levalbuterol HFA MDI with TMAI PRN. The total study duration for a subject will not exceed 10 weeks. This study was previously posted by Sepracor Inc. In October 2009, Sepracor Inc. was acquired by Dainippon Sumitomo Pharma., and in October 2010, Sepracor Incs name was changed to Sunovion Pharmaceuticals Inc. 