Effects of Cannabidiol in Adolescent and Young Adult Depressive and Anxiety Disorders: A Systematic Review of Clinical and Preclinical Research

Background: Adolescents and young adults may use cannabidiol (CBD) products in an attempt to reduce depression and anxiety symptoms, despite little research examining this use. This systematic review evaluated preclinical and clinical research on the effects of CBD on depressive and anxiety disorders in adolescence and young adulthood. To provide context, we discuss CBD's mechanism of action and neurodevelopmental effects. Methods: PubMed was searched for articles published through June 2022. Preclinical or clinical CBD administration studies with N > 1 that examined depressive and/or anxiety disorders were eligible. Results: Initially, 224 publications were identified. After excluding duplicates and applying eligibility criteria, 6 preclinical (depression: n approximate to 133; anxiety: n approximate to 161) and 4 clinical (anxiety: n=113) articles remained. Due to the low number of studies, results were synthesized qualitatively. The Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence were used to rate each study's evidence. The preclinical effects of CBD on depression-like behavior appear to differ by sex, early life stress, and duration of use. Despite no evidence that CBD exerts anxiolytic effects in preclinical adolescent models, CBD may reduce anxiety symptoms in human adolescents and young adults with anxiety disorders. Conclusion: The existing evidence suggests that CBD may reduce symptoms of anxiety in adolescents and young adults. However, the evidence is sparse and limited by variations in samples and CBD dosing duration. Further research is needed to understand the potential benefits and/or harms of CBD for depression and anxiety disorders in this population. Implications for clinical practice and research are discussed.