Asthma sufferers number approximately 200 million worldwide, with 15-20 million of those in the United States. Multiple comorbid conditions occur with asthma, including rhinitis, rhinosinusitis, gastroesophageal reflux disease, sleep apnea, vocal cord dysfunction syndrome, obesity, and chronic obstructive pulmonary disease (COPD). Without identifying and caring for comorbid conditions, asthma cannot be treated appropriately. Comorbidity of allergic diseases emphasizes that we must understand more about why different organs in individuals express allergy and others do not. The increase in...