Background: Pathologic grooming disorders can lead to clinically significant distress and functional impairment. Studies on treatment of these disorders with selective serotonin reuptake inhibitors (SSRIs) and anticonvulsants have led to inconsistent findings. N-acetylcysteine (NAC) has shown promise in treatment of obsessive-compulsive and related disorders. The objective of this article is to perform an updated review of NAC in the treatment of grooming disorders.
Methods: PubMed was searched from inception to October 2017 to identify literature on the use of NAC in the management of trichotillomania, onychophagia, and pathological skin picking. Case reports, case series, and randomized controlled trials were included. Data on study design, dosing regimens, comorbidities, concurrent treatment, and side effects were extracted from the included articles.
Results: Fifteen articles were included in this review, which consisted of 10 case reports, one case series, and four randomized controlled trials. Dosing of oral NAC ranged from 450 to 2,400 mg per day, and treatment periods lasted from 1 to 8 months. Side effects were uncommon, mild, and usually gastrointestinal in nature, with severe aggression reported in one child.
Conclusions: While there are multiple reports of the safety and efficacy of NAC in the treatment of grooming disorders, there are currently few randomized controlled trials on this topic, and more research is needed to develop a formal treatment algorithm. While current data should be considered very preliminary, case reports have demonstrated mostly positive results and a lack of significant side effects. A trial of NAC may be a viable option for pathologic grooming disorders, especially in patients who have failed prior psychologic or pharmacologic treatment.
© 2019 The International Society of Dermatology.