 Patients with significant diseases other than COPD that may either put the patient at risk because of participation in the study or a disease which may influence the results of the study or the patients ability to participate in the study, with a history of asthma or allergic rhinitis, who regularly use daytime oxygen therapy for more than 1 hour per day and in the investigators opinion will be unable to abstain from the use of oxygen therapy or using oral corticosteroid me dication at unstable doses i.e., less than 6 weeks on a stable dose or at a dose in excess of the equivalent of 10 mg of prednisone per day or 20 mg every other day will be excluded. 