[N-acetylcystein in the therapy of chronic bronchitis]

Chronic bronchitis (CB) shows an increasing global morbidity and mortality with major impact on socioeconomics. N-Acetylcysteine (NAC), previously used as a mucolytic compound in CB, has also antioxidative effects. Furthermore it influences intrabronchial bacterial colonisation. In a randomised pilot study of 24 patients (16-male, 8 female, mean age 66 +/- 10 years) with acute exacerbation of CB and positive bacterial culture in the sputum, the addition of twice daily 600 mg NAC to standard antibiotic therapy lead to a significantly higher bacterial eradication rate (70 % versus 36 %, p < 0.03). Clinical studies suggest that treatment with NAC has different effects in CB including a reduction of the number and duration of acute exacerbation episodes and possibly influences lung function. The improvement of symptoms and quality of life also has an impact on socio-economic costs. The use of NAC in CB as an antioxidative rather than a mucolytic compound should be considered. However, further placebo controlled studies are undergoing to definitively establish the role of NAC for the treatment of CB and COPD.