 The NIOX MINO was initially cleared by the FDA on March 4, 2008 as a new hand-held device for the measurement of exhaled Nitric Oxide, a marker of eosinophilic airway inflammation. The most recent clearance by the FDA was on September 2, 2010 for Instrument 09-1100, which will be used in this study. NIOX MINO can be used in children 7-17 years of age and in adults 18 years of age or older in the initial assessment and management of asthma. 