Nail-biting stuff? The effect of N-acetyl cysteine on nail-biting.
N-acetyl cysteine (NAC) is a widely available nutraceutical with a variety of actions. As a precursor of cysteine and glutathione, it has antioxidant properties that may impact on mood and contribute to an effect on impulsivity and obsessive behaviour. Via its additional effect on glutamate via the cystine-glutamate exchange system, NAC has been shown to mediate impulsivity in preclinical models of addiction, reduce craving, and cue extinction. Further, by boosting glutathione, NAC acts as a potent antioxidant and has been shown in two positive, large-scale randomized placebo-controlled trials to affect negative symptoms in schizophrenia and depression in bipolar disorder. We describe three cases in which its actions specifically on nail-biting and associated anxiety may offer a potential treatment. The spontaneous findings are reported as part of an ongoing treatment trial examining the utility of NAC in bipolar disorder. Its actions, if robustly replicated, also point to potential treatment targets in glutathione or glutamate pathways in the brain.
Department of Clinical and Biomedical Sciences, University of Melbourne, Australia. mikebe@barwonhealth.org.au
Michael
M
Berk
Sue
S
Jeavons
Olivia M
OM
Dean
Seetal
S
Dodd
Kirsteen
K
Moss
Clarissa S
CS
Gama
Gin S
GS
Malhi
D000111:Acetylcysteine / Q000627:therapeutic use*; D000328:Adult; D001007:Anxiety / Q000188:drug therapy*; D005260:Female; D016166:Free Radical Scavengers / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009259:Nail Biting
D016166:Free Radical Scavengers; D000111:Acetylcysteine