Objective: To evaluate clinical data using oral n-acetylcysteine (NAC) in obsessive-compulsive and related disorders (OCDRD) treatment.
Data sources: PubMed, Ovid MEDLINE (1946-July 2022), and the Cochrane Library database were searched using the terms NAC, children, adolescent, obsessive-compulsive disorder (OCD), trichotillomania (TTM), excoriation, hoarding disorder, and body dysmorphic disorder. Bibliographies were reviewed for relevant trials and case studies.
Study selection and data extraction: English language, clinical trials, or case studies analyzing NAC use in patients aged 3 to 21 years old with OCDRD as determined by the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition.
Data synthesis: Three randomized double-blind placebo-controlled trials of NAC in children and adolescents studied 121 patients with OCDRD. Trials assessed symptom severity from baseline to 10 to 12 weeks of NAC therapy. Two OCD trials identified statistically significant improvements, with only 1 trial demonstrating a clear clinically relevant difference from placebo. One trial in TTM found no difference between the NAC and placebo. Adverse effects were mild and included nausea, blurred vision, fatigue, tremor, and sweats. N-acetylcysteine titrated to 2400 or 2700 mg/day in divided doses was the most studied regimen.
Relevance to patient care and clinical practice: Many OCDRD patients fail to completely respond to first-line treatment with cognitive behavioral therapy (CBT) and/or selective serotonin reuptake inhibitors (SSRIs) leaving practitioners with few additional treatment options. Preliminary efficacy and safety data are presented in this review.
Conclusions: Limited evidence suggests children and adolescents with OCD refractory to SSRIs or CBT may benefit from NAC augmentation.
Keywords: dietary supplements; glutamate; neuropharmacology; obsessive/compulsive disorder; pediatrics; psychiatry.