N-acetylcysteine effectively treats trichotillomania symptoms

Clinical question Is N-acetylcysteine (Mucomyst) effective in the treatment of trichotillomania?

Bottom line N-acetylcysteine is effective in reducing the symptoms of trichotillomania, but does not significantly improve overall psychosocial functioning. Clinical improvement initially occurred only after at least 9 weeks of treatment. (Level of evidence = 1b)

Synopsis Trichotillomania consists of repetitive hair pulling, leading to noticeable hair loss. N-acetylcysteine may restore the natural balance of brain glutamate levels and reduce compulsive behavior. These investigators identified 50 adults, aged 18 to 59 years, meeting standard criteria for the diagnosis of trichotillomania. Eligible participants randomly received (concealed allocation assignment) N-acetylcysteine, 1,200 mg daily, or matching placebo. After 6 weeks, the dose was doubled for those not showing clinical improvement. The primary assessment tool was a previously validated 7-item scale that rates urges to pull hair, amount of pulling, perceived control of urges, and distress associated with hair pulling (0-4 for each item, for a total of 0-28, with increasing symptom severity indicated by higher scores). Patients masked to treatment group assignment self-reported outcomes. Follow-up occurred for 88% of participants at 12 weeks. Using intention-to-treat analysis, a 50% or greater reduction in severity score compared with baseline occurred significantly more often in patients receiving active treatment than placebo (44% vs 0%; number needed to treat = 2; 95% CI, 1.5-5). However, clinical improvement was first noted after 9 weeks of treatment. A secondary evaluation tool for overall psychosocial functioning and quality of life found no significant difference between the two treatment groups. No significant adverse events occurred in either group.

Grant JE, Odlaug BL, Kim SW. N-acetylcysteine, a glutamate modulator, in the treatment of trichotillomania: a double-blind, placebocontrolled study. Arch Gen Psychiatry. 2009;66(7):756-763.