N-acetylcysteine for therapy-resistant tobacco use disorder: a pilot study

Redox Rep. 2015 Sep;20(5):215-22. doi: 10.1179/1351000215Y.0000000004. Epub 2015 Mar 2.


Introduction: N-Acetylcysteine (NAC) may have efficacy in treating tobacco use disorder (TUD) by reducing craving and smoking reward. This study examines whether treatment with NAC may have a clinical efficacy in the treatment of TUD.

Methods: A 12-week double blind randomized controlled trial was conducted to compare the clinical efficacy of NAC 3 g/day versus placebo. We recruited 34 outpatients with therapy resistant TUD concurrently treated with smoking-focused group behavioral therapy. Participants had assessments of daily cigarette use (primary outcome), exhaled carbon monoxide (CO(EXH)) (secondary outcome), and quit rates as defined by CO(EXH) < 6 ppm. Depression was measured with the Hamilton Depression Rating Scale (HDRS). Data were analyzed using conventional and modified intention-to-treat endpoint analyses.

Results: NAC treatment significantly reduced the daily number of cigarettes used (Δ mean ± SD = -10.9 ± 7.9 in the NAC-treated versus -3.2 ± 6.1 in the placebo group) and CO(EXH) (Δ mean ± SD = -10.4 ± 8.6 ppm in the NAC-treated versus -1.5 ± 4.5 ppm in the placebo group); 47.1% of those treated with NAC versus 21.4% of placebo-treated patients were able to quit smoking as defined by CO(EXH) < 6 ppm. NAC treatment significantly reduced the HDRS score in patients with tobacco use disorder.

Conclusions: These data show that treatment with NAC may have a clinical efficacy in TUD. NAC combined with appropriate psychotherapy appears to be an efficient treatment option for TUD.

Keywords: Depression; Glutathione.; Inflammation; N-Acetylcysteine; Oxidative stress; Smoking cessation.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcysteine / administration & dosage
  • Acetylcysteine / therapeutic use*
  • Adolescent
  • Adult
  • Aged
  • Double-Blind Method
  • Female
  • Glutathione / metabolism
  • Humans
  • Male
  • Middle Aged
  • Oxidative Stress / drug effects
  • Pilot Projects
  • Tobacco Use Disorder / drug therapy*
  • Tobacco Use Disorder / metabolism
  • Treatment Outcome
  • Young Adult


  • Glutathione
  • Acetylcysteine