Elsevier created a COVID-19 resource centre in January 2020, offering free information in English and Mandarin. The centre is hosted on Elsevier Connect, and the company grants permission for free access to its research in PubMed Central and other repositories for unrestricted reuse. The article discusses COPD exacerbations, which are worsening episodes of symptoms leading to significant morbidity and mortality. These exacerbations are often triggered by respiratory viruses and bacteria, causing airway and systemic inflammation. Pharmacological treatments like inhaled steroids and long-acting bronchodilators help reduce exacerbation frequency and severity, while non-pharmacological therapies such as pulmonary rehabilitation and self-management are increasingly important. COPD exacerbations are complex, with some patients being more susceptible. They are associated with increased airway inflammation, hyperinflation, and systemic inflammation. Definitions of exacerbations vary, with some based on healthcare use, such as hospital admission or antibiotic use. The latest GOLD guidelines suggest that some exacerbations may be self-limiting. Exacerbations are often inflammatory events, with several markers increasing. Research into biomarkers is ongoing, with studies showing that combinations of biomarkers can improve diagnostic accuracy. Pathophysiological changes include increased airway and systemic inflammation, with studies showing increased neutrophils and inflammatory markers during exacerbations. COPD exacerbations are caused by a complex interaction of host factors, viruses, bacteria, and environmental pollution. Viral infections, particularly respiratory viruses like rhinovirus, are common triggers, often leading to more severe exacerbations. Bacterial infections also play a role, with studies showing that antibiotics can reduce exacerbation severity. However, the role of bacteria in exacerbations is not fully understood. Environmental pollution is a significant factor, with increased pollution levels linked to more frequent and severe exacerbations. COPD exacerbations have functional consequences, including reduced physical activity and increased hospital admissions. Patients with frequent exacerbations have worse quality of life and higher mortality. Pharmacological therapies include vaccines, inhaled corticosteroids, long-acting bronchodilators, and phosphodiesterase inhibitors. Vaccines like influenza and pneumococcal vaccines are recommended for COPD patients. Inhaled corticosteroids and long-acting beta-agonists (LABAs) have shown benefits in reducing exacerbation frequency. Tiotropium, a long-acting anticholinergic, also reduces exacerbation frequency. Non-pharmacological therapies include pulmonary rehabilitation and self-management, which can reduce exacerbation severity and hospital admissions. Home oxygen therapy and non-invasive ventilation are used in severe cases. However, the evidence for mucolytic agents in preventing exacerbations is not convincing. The article concludes that while many interventions help prevent COPD exacerbations, more research is needed to develop new and effective strategies. Combinations of interventions are likely to be most effective, and future studies should focus on well-designed, adequately powered trials.Elsevier created a COVID-19 resource centre in January 2020, offering free information in English and Mandarin. The centre is hosted on Elsevier Connect, and the company grants permission for free access to its research in PubMed Central and other repositories for unrestricted reuse. The article discusses COPD exacerbations, which are worsening episodes of symptoms leading to significant morbidity and mortality. These exacerbations are often triggered by respiratory viruses and bacteria, causing airway and systemic inflammation. Pharmacological treatments like inhaled steroids and long-acting bronchodilators help reduce exacerbation frequency and severity, while non-pharmacological therapies such as pulmonary rehabilitation and self-management are increasingly important. COPD exacerbations are complex, with some patients being more susceptible. They are associated with increased airway inflammation, hyperinflation, and systemic inflammation. Definitions of exacerbations vary, with some based on healthcare use, such as hospital admission or antibiotic use. The latest GOLD guidelines suggest that some exacerbations may be self-limiting. Exacerbations are often inflammatory events, with several markers increasing. Research into biomarkers is ongoing, with studies showing that combinations of biomarkers can improve diagnostic accuracy. Pathophysiological changes include increased airway and systemic inflammation, with studies showing increased neutrophils and inflammatory markers during exacerbations. COPD exacerbations are caused by a complex interaction of host factors, viruses, bacteria, and environmental pollution. Viral infections, particularly respiratory viruses like rhinovirus, are common triggers, often leading to more severe exacerbations. Bacterial infections also play a role, with studies showing that antibiotics can reduce exacerbation severity. However, the role of bacteria in exacerbations is not fully understood. Environmental pollution is a significant factor, with increased pollution levels linked to more frequent and severe exacerbations. COPD exacerbations have functional consequences, including reduced physical activity and increased hospital admissions. Patients with frequent exacerbations have worse quality of life and higher mortality. Pharmacological therapies include vaccines, inhaled corticosteroids, long-acting bronchodilators, and phosphodiesterase inhibitors. Vaccines like influenza and pneumococcal vaccines are recommended for COPD patients. Inhaled corticosteroids and long-acting beta-agonists (LABAs) have shown benefits in reducing exacerbation frequency. Tiotropium, a long-acting anticholinergic, also reduces exacerbation frequency. Non-pharmacological therapies include pulmonary rehabilitation and self-management, which can reduce exacerbation severity and hospital admissions. Home oxygen therapy and non-invasive ventilation are used in severe cases. However, the evidence for mucolytic agents in preventing exacerbations is not convincing. The article concludes that while many interventions help prevent COPD exacerbations, more research is needed to develop new and effective strategies. Combinations of interventions are likely to be most effective, and future studies should focus on well-designed, adequately powered trials.