Acute exacerbation of COPD is characterized by one or more key symptoms. Eighty percent of the cases of AECOPD are due to infection. Treatment of AECOPD is based on the number of key symptoms and risk factors that are present. Antibiotic treatment shows some immediate clinical benefits and may also minimize the frequency of further recurrences. A newer macrolide, extended-spectrum cephalosporin, or doxycycline is appropriate for an exacerbation of moderate severity, while high-dose amoxicillin/clavulanate or a respiratory fluoroquinolone should be used for a severe exacerbation. Exacerbations of chronic bronchitis are a common occurrence in clinical practice. Undoubtedly, every episode induces a temporary decline in lung function and may therefore pose a threat of respiratory failure or death in more severely obstructed patients. In conclusion, the role of antibiotic treatment in chronic bronchitis exacerbations seems to be confirmed in terms of mid-term functional recovery, and to be relevant to patients with severe functional impairment and higher number of exacerbations per year in whom antibiotic treatment induces the greatest benefit.