Anti-inflammatory Activity and Mucolytic Effect of Ambroxol in Patients with Stable Chronic Bronchitis-A Preliminary Report

Abstract

Chronic bronchitis is a clinical disorder characterized by excessive mucus secretions and manifested by chronic or productive cough on most days, for a minimum of 3 months in a year and for not less than 2 successive years. Unfortunately, other disorders with similar manifestations, such as bronchiectasis, tuberculosis, and lung abscess, must be excluded. Patients with predominant asthma or emphysema may fit this definition, and many patients with pathological or physiological hallmarks or chronic bronchitis may not qualify, since they do not cough. Hyper-viscosity and overproduction of sputum often increase morbidity. Mucolytics might alleviate patients' symptoms and improve their daily activity. Ambroxol was first introduced as a mucoactive agent with anti-inflammatory activity. We investigated the benefits of this compound in reducing cytokine concentrations of sputum, sputum viscosity, and pulmonary symptoms in chronic bronchitis patients. Twenty-five chronic bronchitis patients were recruited and 20 completed the study. We found that 2-week oral administration of ambroxol did not improve static lung function (FVC, FEV1 and FEV1%) and 6-minute walking test distance. The sputum myeloperoxidase (MPO) activity and IL-8 level were reduced significantly, the sputum TNF-α and IL-1β levels had a tendency to decrease, and the measured sputum viscosity at 1 radian was significantly reduced. These preliminary results support the assumption that ambroxol is a mucolytic agent with anti-inflammatory activity, which might be helpful in terms of sputum clearance and reduction of airway inflammation in chronic bronchitis patients.