Objective: An imbalance between oxidants-antioxidants is known to play an important role in the pathogenesis of asthma, especially during exacerbation. The aim of this study was to investigate the effect of N-acetyl-L-cysteine (NAC) treatment on the levels of sputum nitrit (NO₂^-) and reduced glutathione (GSH) contents in patients with asthma during exacerbations.

Materials and Methods: The study had a double blind, placebo controlled design. Induced sputum GSH, NO₂ ^-, cell counts and plasma NO₂ ^– contents were evaluated in 11 healthy controls (HCs) and 25 patients with asthma during exacerbation before and after treatment. Fifteen patients with acute asthma attack were treated with inhaled NAC during exacerbation.

Results: Plasma-sputum NO₂ ^- and sputum GSH contents were significantly higher in subjects with asthma subgroups than HCs (p<0.01 for NAC treatment group, p<0.005 for placebo treatment group, for plasma NO₂ ^-; p<0.001 for both groups for sputum NO₂ ^-; p<0.001 for both groups for sputum GSH). NAC treatment group had higher GSH contents in sputum samples after treatment which were, however, not significantly different from those before treatment. There was a significant decrease in sputum (p<0.005 for NAC treatment group, p<0.01 for placebo group) and plasma NO₂ ^- (p<0.005 for NAC treatment group, p<0.01 for placebo group) levels in both NAC treatment group and placebo group after treatment when compared with the pretreatment levels.

Conclusion: These findings indicated that addition of NAC to standard attack therapy does not modify the oxidant-antioxidant status in asthma patients during exacerbation.©2008, Firat University, Medical Faculty.