Chronic obstructive pulmonary disease (COPD) and chronic bronchitis are highly prevalent diseases. Studies designed to analyze the economic impact of these diseases in Latin American countries have not previously been published. In the present study we analyzed the direct health care costs of treating patients with exacerbations of chronic bronchitis and COPD in Argentina, Brazil, Colombia, Ecuador, Mexico, Peru, and Venezuela, applying the real cost of drugs and medical acts in those 7 countries to the pattern of treatment and outcomes obtained from a study carried out in primary care settings in Spain. The mean direct health care cost ranged from US $98 in Colombia to $329 in Argentina. Most of the cost was related to failure of therapy, which accounted for 52% of the total cost of exacerbation, with the lowest rate in Colombia at 28.6% and the highest in Ecuador at 59.3% The cost of antibiotic therapy represented 19% of the total cost; the rest was owing to other drugs or medical visits. Exacerbations generate significant costs for health care systems. There are considerable variations related mainly to differences between systems. Antibiotic therapy represents a small part of the overall cost. The use of more effective antibiotics, if they can reduce failure rates, may be a cost-effective strategy.