Patients with asthma and concomitant allergic rhinitis are among the most costly patients. A survey of over 34,000 patients with asthma indicated that the cost of those patients who have asthma alone without allergic rhinitis was roughly half the overall cost of patients who had concomitant allergic rhinitis and asthma. Asthma and allergic rhinitis are linked in several ways. The shared immunologic pathogenesis are nasal bronchial reflex, allergen sensitization, and epidemiologic studies that link asthma and allergy. There is an interrelatedness of the upper and lower airway function, the link operating directionally from the sinuses to the lungs. In addition, there is a co-occurrence of asthma and allergic rhinitis in the population. Furthermore, both conditions respond to similar treatments, including antihistamine-containing therapies that may ameliorate allergic rhinitis and also potentially help alleviate asthma symptoms.