Controlled trial of oral N-acetylcysteine in cystic fibrosis

To assess the efficacy of oral N-acetylcysteine (NAC) 200mg given thrice daily in cystic fibrosis (CF) we conducted a double blind placebo controlled cross over trial on 20 patients with mild to moderate pulmonary disease. No significant difference between the 3 month treatment periods with NAC and placebo were detected on daily peak expiratory flow rates (PEFR), subjective sputum viscosity, and cough frequency scores. Neither was there any statistically significant difference in weight gain, antibiotic usage or chest radiograph (CXR) scores.