A Pilot Examination of Oxidative Stress in Trichotillomania

The Potential of N-Acetyl-L-Cysteine (NAC) in the Treatment of Psychiatric Disorders

N-acetyl-L-cysteine (NAC) is a compound of increasing interest in the treatment of psychiatric disorders. Primarily through its antioxidant, anti-inflammatory, and glutamate modulation activity, NAC has been investigated in the treatment of neurodevelopmental disorders, schizophrenia spectrum disorders, bipolar-related disorders, depressive disorders, anxiety disorders, obsessive compulsive-related disorders, substance-use disorders, neurocognitive disorders, and chronic pain. Whilst there is ample preclinical evidence and theoretical justification for the use of NAC in the treatment of multiple psychiatric disorders, clinical trials in most disorders have yielded mixed results. However, most studies have been underpowered and perhaps too brief, with some evidence of benefit only after months of treatment with NAC. Currently NAC has the most evidence of having a beneficial effect as an adjuvant agent in the negative symptoms of schizophrenia, severe autism, depression, and obsessive compulsive and related disorders. Future research with well-powered studies that are of sufficient length will be critical to better understand the utility of NAC in the treatment of psychiatric disorders.

Recent advances in the treatment of trichotillomania (hair-pulling disorder)

Trichotillomania (TTM) is a condition in which affected individuals pull out their hair resulting in hair loss. This disorder affects roughly 0.5% to 2.0% of the population and can have significant psychological morbidity. Behavioral therapy has been used with success in the treatment of TTM, but not all patients are willing or able to comply with this treatment strategy. There is a need for effective pharmacological treatment options. Historically, pharmacotherapy for TTM has been inadequate in most cases, but recent advances have been made in this regard. Fluoxetine, clomipramine, olanzapine, and naltrexone have all been used in the treatment of TTM, but evidence of benefit has varied, and side effect profiles can limit practical utility. Recent advances in the understanding of the pathophysiology of TTM, as well as evidence of benefit seen with some glutamate-modulating agents such as N-acetylcysteine and dronabinol, have provided newer potential pharmacotherapy options.

Milk Thistle Treatment for Children and Adults with Trichotillomania: A Double-Blind, Placebo-Controlled, Crossover Negative Study

BACKGROUND

Data on the pharmacological treatment of trichotillomania are limited. Milk thistle has antioxidant properties and showed promise in trichotillomania in a prior case report. The goal of the current study was to determine the efficacy and tolerability of silymarin in children and adults with trichotillomania.

METHODS

Twenty individuals (19 [95.0%] women; 16 adults; mean age, 27.9 [11.5] years) with trichotillomania entered a 12-week, double-blind, placebo-controlled crossover study (6 weeks of milk thistle and 6 weeks of placebo with a 1-week wash-out in between). Dosing of milk thistle ranged from 150 mg twice a day to 300 mg twice a day. Subjects were assessed with the National Institute of Mental Health Trichotillomania Severity Scale (primary outcome), the Massachusetts General Hospital Hair Pulling Scale, Clinical Global Impression scale, and measures of depression, anxiety, and psychosocial functioning. Outcomes were examined using linear mixed models with a random intercept for subject and t tests.

RESULTS

There were no statistically significant treatment type-by-time interactions for the main outcome measure, but significant effects were seen for secondary measures (eg, time spent pulling per day for the past week). From baseline to week 6, there was a significant decrease in Clinical Global Impression severity for the milk thistle group but not in the placebo group.

CONCLUSIONS

This trial failed to show that milk thistle was more effective than placebo on the main outcome measure, but milk thistle did demonstrate significant improvements on select secondary outcome measures. These findings may shed light on important neurochemical targets worthy of future investigation.