High-dose N-acetylcysteine in stable COPD: the 1-year, double-blind, randomized, placebo-controlled HIACE study.

Background: The mucolytic and antioxidant effects of N-acetylcysteine (NAC) may have great value in COPD treatment. However, beneficial effects have not been confirmed in clinical studies, possibly due to insufficient NAC doses and/or inadequate outcome parameters used. The objective of this study was to investigate high-dose NAC plus usual therapy in Chinese patients with stable COPD.