A 10 year old male with asthma returns to his physician for follow up. Two months ago, his teacher noted him wheezing after playing on the playground, and pulmonary function testing confirmed a diagnosis of asthma. Since that time, he has been using a rescue inhaler approximately one time a week at school to relieve wheezing and chest tightness that seem to occur following strenuous activity. He has also been using his rescue inhaler approximately one time a week at home at night when he awakens with chest tightness or difficulty breathing. Current medications include albuterol and atomoxetine. On physical exam, the patient is comfortable and afebrile. The patient's lungs are clear to auscultation, and no wheezing or prolonged expiration is noted. What is the most appropriate next step in the management of this patient?
1) Increase the dose of albuterol
2) Add a long-acting beta-agonist
3) Add an inhaled corticosteroid
4) Discontinue atomoxetine