In recent years, acute bronchitis has become one of the most widespread lung diseases. Therefore, there is a need for effective prevention and treatment procedures, with nutrition being one of the important factors to be taken into account. The present paper discusses the properties and efficacy of a new plant based dietary supplement that contains ingredients with synergistic properties and can be successfully applied to regulate metabolism when treating bronchopulmonary pathology. The plant based dietary supplement was administered to enhance the traditional treatment. One capsule was taken by the patients of the experimental group three times a day at breakfast, lunch and dinner for the period of 30 days. While the control group did not receive the plant based dietary supplement and undertook the standard form of treatment. By comparing all the data collected during the clinical trial, positive impact of the new plant based dietary supplement was observed, i.e. the exacerbation phase was shortened by two or three days, the period of the hospital treatment was reduced by five and a half days. Alongside the ease of the shortness of breath, improved lung function and lung vital capacity, were the increased volume of forced inhalation, the rallied mucociliary apparatus, and bronchial mucosal swelling reduction. The experimental group patients demonstrated both the increased tocopherol level and the growth in oxygen concentration. The positive changes were observed in metabolic process, i.e. lipid peroxidation, which in turn provides better exercise capacity. The data collected during the clinical trial is of huge importance and can help improve the life of the patients with acute bronchitis. Active ingredients of the new plant based dietary supplement influence both the chemistry of lipid peroxidation and antioxidant protection process against free-radical damage. This influence is particularly notable in the early stages of the disease. The clinical trial findings indicate that administering the new plant based dietary supplement as a part of a standard treatment is justified and effective. Moreover, the supplement can be successfully taken to prevent the acute bronchitis.