Of Types of outcome measures the Figure 6mucolytiAnalysis 2.3c drugs Danmarks Radio availableNakayama 1977, the cCollet 1991ysteine derivatives (that is, acetylcysteine and carbocysteine) are the most commonly prescribed in many European countries (Chalumeau 2000; Duijvestijn 1997). In vitro, they act bTable 2y breaking Table 1disulphide bridges between macromolSummary of findings table 1ecules, which leads to a reduction in mucus viscosity (Medici 1979). This property led Feedback 1physiciansAppendix 1 in the 1960s and 1970s toOngoing studies develop mucolyticData and analyses Sources of support Feedback Appendices drugs for clinical situations where sputum modification to reduce cough is sought, including cystic fibrosis, and chronic and acute bronchitis. In adult patients, the use of cysteine derivatives is associated with a s Summary of findings table 1 mall reduction in acute exacerbations of chronic Feedback bronchitis (Poole 1998). In paediatric patients with cystic fibrosis, there is no evidence of effectiveness of either oral or inhaled administration of acetylcysteine (Duijvestijn 1999). Data and analyses Sources of support Feedback Appendices2...