Placebo Versus Antibiotics in Acute Exacerbations of Chronic Obstructive Pulmonary Disease (COPD)

Inclusion Criteria: * Acute exacerbation of COPD type I or II according to GOLD * Ability to perform lung function tests * Ability to take oral medication Exclusion Criteria: * Pregnant or lactating women, or women of childbearing age not using an acceptable method of contraception. * Pretreatment ( \> 24 hours) with an antibiotic for the present exacerbation. * Pretreatment with corticosteroids (\>30 mg for more than 4 days) for the present exacerbation. * Progression or new radiographic abnormalities on the chest X-ray. * Severe exacerbation that required mechanical ventilation. * History of bronchiectasis * Recent or unresolved lung malignancy. * Other disease likely to require antibiotic therapy. * Significant gastrointestinal or other conditions that may affect study drug absorption. * Class III or IV congestive heart failure or stroke. * Immunodeficiency disorders such as AIDS, humoral immune defect, ciliary dysfunction etc. and the use of immunosuppressive drugs (\>30 mg prednisolone maintenance dose or equivalent for more than 4 weeks). * Cystic fibrosis * Tuberculosis. * Impaired renal function (creatinine clearance \< 20 ml/min).