Azithromycin Treatment for the Airway Microbiome in Asthma

Inclusion criteria (All participants): 1. Age 18 - 55 years 2. Able to provide informed consent 3. Smoking history \< 10 pack-years Inclusion Criteria for subjects with poorly controlled asthma 1. Methacholine PC20 \< 16 mg/ml or PD 20 \< 400 mcg/ml or albuterol response \> 12% on FEV1 after 4 puffs of albuterol 2. Currently prescribed ICS + LABA 3. Meet definition for Th2-low asthma: peripheral blood eosinophil count \< 300 and exhaled nitric oxide level \< 30 ppb. Exclusion Criteria (All participants) 1. History of allergy or intolerance to any medications used in this study 2. Medication exclusions: 1. Current use of medications that prolong QTc interval 2. Current use of omalizumab or other ant-IgE therapies 3. Current use of anti-IL 5 therapies 4. Current use of anticoagulants 3. Prednsione or other oral steroids within past 3 months 4. Pregnancy or lactation, or plans to become pregnant 5. Other respiratory or inflammatory disorders (e.g., sarcoidosis, emphysema) 6. Pre-existing liver disease by history 7. Smoking within the last 6 months 8. Exacerbation of asthma in past 3 months 9. Affected by a hearing disorder 10. Clinically significant medical condition (e.g., heart failure, seizure disorder) which may in-crease risk as determined by study investigator 11. Corrected QT interval \> 450 msec. Patients with known cardiac history or prolonged QT interval on a screening EKG are excluded given the small but real potential for macrolide-related side effects