We were impressed by a recent study of n-acetyl cysteine as a treatment for marijuana dependence. It was a well designed study from a very reputable research group and the results were significant: the number of clean urines in the group getting NAC was twice as high as in the placebo group.
It got us more interested in the agent and other potential uses for it.
N-acetyl cysteine (NAC) is a modified form of the dietary amino acid cysteine. It is not found in food.
NAC is thought to help the body make the important antioxidant enzyme glutathione. It also has direct antioxidant effects. And, by blocking action of the excitatory neurotransmitter glutamate, it reduces brain damage in a number of situations (such as stroke and possibly stress) associated with excessive brain activation. Finally it increases the release of the neurotransmitter dopamine. A summary of these effects is to be found in this picture.
It has shown promise for a number of conditions, especially chronic bronchitis.
Optimal levels of NAC have not been determined. The amount used in studies has varied from 250 to 1,500 mg daily.
The dose in the marijuana study was 1200 mg a day. And it is reasonable to use that does since it seems to be quite safe.
Several studies have suggested that NAC may be beneficial as an aid to treating various mental health disorders including schizophrenia, hair pulling, cocaine-dependence, and even pathological gambling.
One study found that it may be helpful for the depressive phase of bipolar.
NAC appears to be a very safe supplement by itself, although one study of rats suggested that doses that are 60 to 100 times the normal dose can cause liver injury.
The combination of nitroglycerin and NAC can cause severe headaches. Safety in young children, women who are pregnant or nursing, and individuals with severe liver or kidney disease has not been established.
Unfortunately, Consumer Laboratories, which is the only reputable source of information about the quality of supplements, has not yet tested NAC supplements. Still these sources appear to be reputable…
REFERENCES
Berk M, Copolov DL, Dean O, et al. N-acetyl cysteine for depressive symptoms in bipolar disorder–a double-blind randomized placebo-controlled trial. Biol Psychiatry. 2008;64:468–75.
Dean O, Giorlando F, Berk M. N-acetylcysteine in psychiatry: current therapeutic evidence and potential mechanisms of action. J Psychiatry Neurosci. 2011 Mar;36(2):78-86.
Grant JE, Kim SW, Odlaug BL. N-acetyl cysteine, a glutamate-modulating agent, in the treatment of pathological gambling: a pilot study. Biol Psychiatry. 2007 Apr 17.
Grant JE, Odlaug BL, Kim SW. N-acetylcysteine, a glutamate modulator, in the treatment of trichotillomania: a double-blind, placebo-controlled study. Arch Gen Psychiatry. 2009 Jul;66(7):756-63.
Gray KM, Carpenter MJ, Baker NL, et al. A Double-Blind Randomized Controlled Trial of N-Acetylcysteine in Cannabis-Dependent Adolescents. Am J Psychiatry 2012;169:805-812.
Larowe SD, Myrick H, Hedden S, et al. Is cocaine desire reduced by N-acetylcysteine? Am J Psychiatry. 2007;164:1115-1117.
Berk M, Copolov D, Dean O, et al. N-acetyl cysteine as a glutathione precursor for schizophrenia—A double-blind, randomized, placebo-controlled trial. Biol Psychiatry. 2008 Apr 22.