N-acetyl cysteine in the treatment of obsessive compulsive and related disorders: a systematic review.
OBJECTIVE
Obsessive compulsive and related disorders are a collection of debilitating psychiatric disorders in which the role of glutamate dysfunction in the underpinning neurobiology is becoming well established. N-acetyl cysteine (NAC) is a glutamate modulator with promising therapeutic effect. This paper presents a systematic review of clinical trials and case reports exploring the use of NAC for these disorders. A further objective was to detail the methodology of current clinical trials being conducted in the area.


METHODS
PubMed, Web of Science and Cochrane Library Database were searched for human clinical trials or case reports investigating NAC in the treatment of obsessive compulsive disorder (OCD) or obsessive compulsive related disorders. Researchers with known involvement in NAC studies were contacted for any unpublished data.


RESULTS
Four clinical trials and five case reports/series were identified. Study durations were commonly 12-weeks, using 2,400-3,000 mg/day of NAC. Overall, NAC demonstrates activity in reducing the severity of symptoms, with a good tolerability profile and minimal adverse effects. Currently there are three ongoing randomized controlled trials using NAC for OCD (two adults and one pediatric), and one for excoriation.


CONCLUSIONS
Encouraging results have been demonstrated from the few pilot studies that have been conducted. These results are detailed, in addition to a discussion of future potential research.
Department of Psychiatry, The Melbourne Clinic, The University of Melbourne, Melbourne, Australia.
Georgina
G
Oliver
Department of Psychiatry, The Melbourne Clinic, The University of Melbourne, Melbourne, Australia.|Innovation in Mental and Physical Health and Clinical Treatment: Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.|The Florey Institute of Neuroscience and Mental Health, Australia.
Olivia
O
Dean
Centre for Human Psychopharmacology, Swinburne University, Melbourne, Australia.|Illawarra Health and Medical Research Institute (IHMRI), Australia.|School of Psychology, University of Wollongong, Wollongong, Australia.
David
D
Camfield
Department of Psychiatry, The Melbourne Clinic, The University of Melbourne, Melbourne, Australia.
Scott
S
Blair-West
Department of Psychiatry, The Melbourne Clinic, The University of Melbourne, Melbourne, Australia.
Chee
C
Ng
Department of Psychiatry, The Melbourne Clinic, The University of Melbourne, Melbourne, Australia.|Innovation in Mental and Physical Health and Clinical Treatment: Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.|The Florey Institute of Neuroscience and Mental Health, Australia.|Centre for Human Psychopharmacology, Swinburne University, Melbourne, Australia.
Michael
M
Berk
Department of Psychiatry, The Melbourne Clinic, The University of Melbourne, Melbourne, Australia.|Centre for Human Psychopharmacology, Swinburne University, Melbourne, Australia.
Jerome
J
Sarris
Glutamate; Obsessive-compulsive disorder; Review; Trichotillomania; acetylcysteine; systematic