N-acetylcysteine augmentation in serotonin reuptake inhibitor refractory obsessive-compulsive disorder

Psychopharmacology (Berl). 2006 Jan;184(2):254-6. doi: 10.1007/s00213-005-0246-6. Epub 2005 Dec 22.


Rationale: Dysfunction of glutamatergic neurotransmission has been implicated in the pathophysiology of obsessive-compulsive disorder (OCD) and recent clinical reports suggest that some glutamate modulating agents are efficacious in the treatment of this disorder. N-acetylcysteine (NAC) is a readily available amino acid compound that is thought to attenuate glutamatergic neurotransmission. NAC may be useful in treating psychiatric disorders involving glutamatergic dysfunction such as OCD.

Objectives: To examine the efficacy of augmentation with NAC in a patient with serotonin reuptake inhibitor (SRI)-refractory OCD.

Methods: A patient with SRI-refractory OCD was treated with an off-label use of NAC augmentation of fluvoxamine over several weeks.

Results: NAC augmentation of fluvoxamine resulted in a marked decrease in Yale-Brown Obsessive Compulsive Scale (Y-BBOCS) score and a clinically significant improvement in OCD symptoms.

Conclusions: NAC augmentation was effective in treating SRI-refractory OCD in this single case. Further research is warranted to investigate the use of NAC and other glutamate modulating agents in the treatment of OCD.

Publication types

  • Case Reports
  • Letter
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acetylcysteine / therapeutic use*
  • Drug Resistance
  • Drug Synergism
  • Female
  • Fluvoxamine / therapeutic use*
  • Humans
  • Middle Aged
  • Obsessive-Compulsive Disorder / drug therapy*
  • Obsessive-Compulsive Disorder / psychology
  • Psychiatric Status Rating Scales
  • Serotonin Uptake Inhibitors / therapeutic use*


  • Serotonin Uptake Inhibitors
  • Fluvoxamine
  • Acetylcysteine