Effect on Adrenal Function of Budesonide Versus Fluticasone in Chronic Obstructive Pulmonary Disease (COPD)

National Institute for Clinical Excellence (NICE) guidelines recommend high dose inhaled steroids for patients with moderate to severe Chronic Obstructive Pulmonary Disease (COPD, a common chronic disease related to smoking) who are having two or more exacerbations requiring treatment with antibiotics or oral steroids in a 12 month period. The preparations licensed for this indication commercially available are Symbicort® and Seretide®. High dose inhaled steroids (contained in both) can cause suppression of the adrenal glands. The investigators want to assess adrenal suppression caused by the two preparations and compare. The results could guide investigators in prescribing these preparations.