Medicinal cannabis for the treatment of anxiety disorders

Abstract

Background: Anxiety is second most common reason for medicinal cannabis prescription in Australia and is being treated with both Δ9-tetrahydrocannabinol (THC)-containing and cannabidiol (CBD)-dominant products.

Objective: The aim of this article is to summarise recent advances in the understanding of medicinal cannabis in treating anxiety and recent trends in prescribing.

Discussion: Clinical trials and laboratory studies provide evidence of anxiolytic effects of CBD in healthy volunteers and clinical populations, although current evidence is insufficient to support CBD as a first-line treatment. The evidence regarding the use of THC-dominant products for anxiety is ambiguous, with exacerbation of anxiety in some individuals and relief in others. Caution is required as THC can impair driving and cognitive function. Despite the lack of robust supportive evidence, prescription of medicinal cannabis products for anxiety is increasing rapidly, while illicit cannabis is widely used in the community to self-medicate anxiety. Approximately 17% of current prescriptions for anxiety are for CBD- dominant liquid products (oils), wafers and capsules, while the remainder are for THC-containing liquid products (33%) and herbal cannabis for vaporisation (50%). Medical practitioners should carefully consider potential risks and benefits when prescribing medicinal cannabis for anxiety disorders and should 'start low and go slow'.