N-Acetylcysteine, a Glutamate Modulator, in the Treatment of Trichotillomania: A Double-blind, Placebo-Controlled Study Archives of General Psychiatry, 07/08/09 Grant JE et al -This study found that N-acetylcysteine demonstrated statistically significant reductions in trichotillomania symptoms. No adverse events occurred in the N-acetylcysteine group, and N-acetylcysteine was well tolerated. Pharmacologic modulation of the glutamate system may prove to be useful in the control of a range of compulsive behaviors.Trial Methods * Twelve-week, double-blind, placebo-controlled trial * Fifty individuals with trichotillomania (45 women and 5 men; mean [SD] age, 34.3 [12.1] years) * N-acetylcysteine (dosing range, 1200-2400 mg/d) or placebo was administered for 12 weeks. * Patients were assessed using the Massachusetts General Hospital Hair Pulling Scale, the Clinical Global Impression scale, the Psychiatric Institute Trichotillomania Scale, and measures of depression, anxiety, and psychosocial functioning. * Outcomes were examined using analysis of variance modeling analyses and linear regression in an intention-to-treat population. Results * Patients assigned to receive N-acetylcysteine had significantly greater reductions in hair-pulling symptoms as measured using the Massachusetts General Hospital Hair Pulling Scale (P < .001) and the Psychiatric Institute Trichotillomania Scale (P = .001). * Fifty-six percent of patients "much or very much improved" with N-acetylcysteine use compared with 16% taking placebo (P = .003). Significant improvement was initially noted after 9 weeks of treatment.