Patients with chronic obstructive pulmonary disease (COPD) are at high risk for poor COVID-19 outcomes. To answer the question why patients with COPD are susceptible to severe COVID-19, experts suggest looking at various aspects, including angiotensin-converting enzyme type 2 (ACE2) expression, smoking, innate immune dysregulation, acquired immune status disorders in patients with COPD. On the other hand, the risks for patients with COPD increase due to the characteristic features of the pathogenesis of COVID-19, such as hypoxemia against the background of lung tissue damage, diffuse damage and swelling of the alveoli, thrombotic complications, and ventilation-perfusion imbalance. In a pandemic or a continuing significant postpandemic incidence of COVID-19, it is important to provide a complete pharmacological treatment of COPD to prevent the development of any exacerbation of the disease, including complications developing against the background of infection with the SARS-CoV-2 virus. With the development of COPD exacerbation, therapeutic recommendations should be followed, which do not lose their relevance during the COVID-19 pandemic. Several classes of drugs are recommended to quickly eliminate the symptoms of an exacerbation and reduce the risk of severe course and complications; these primarily include bronchodilators, glucocorticosteroids, antibiotics, and mucoactive drugs. Mucolytics are used to improve mucociliary clearance in COPD, in addition, they have antioxidant and anti-inflammatory properties. Mucolytic therapy is not the primary pharmacological option in the management of a patient with COPD exacerbation, however, the addition of an effective mucolytic, such as N-acetylcysteine, can lead not only to a decrease in the viscosity of the bronchial secretion and improve its expectoration, but also to a decrease in clinical symptoms and an increase in functional parameters. Moreover, N-acetylcysteine therapy may reduce the risk of future COPD exacerbations.

Keywords: mucolytic therapy for COPD, COVID-19, N-acetylcysteine, pharmacotherapy, chronic obstructive pulmonary disease