The anxiolytic effects of cannabis based medicinal products (CBMPs) have been touted for decades. Medical cannabis was legalised in the UK in November 2018 and observational, prospective studies of private prescriptions have demonstrated that patients taking CBMPs show significant reductions in anxiety. CBMPs vary in cannabinoid content, including their cannabidiol (CBD) & delta-9-tetrahydrocannabinol (THC) content and formulation (e.g. oil, oral capsule, vaporised flower). There is promising evidence that CBD may reduce social anxiety following a single dose in laboratory-models and following four weeks of daily treatment. However, more research is needed to unpack the separate and combined anxiolytic effects of CBD and THC.
The overarching aims of the project are: (1) understand the long-term, real-world associations between use of different CBMPs and anxiety outcomes; (2) test the separate and combined acute effects of CBD and THC on state anxiety in vulnerable individuals.
Study 1 (Year 1): meta-analysis of CBD’s anxiolytic effects in the lab and meta-analysis of prospective associations between CBMP usage and reduced anxiety.
Study 2 (Year 1 & 2): mega-analysis of combined prospective, observational studies tracking CBMP patients’ anxiety levels, moderated by CBMP type.
Study 3 (Years 2 & 3): a randomised, placebo-controlled, double-blind, crossover, non-CTIMP experiment comparing the one-off effects of: placebo, oral CBD (800mg), dronabinol (oral THC, 5mg), and CBD (800mg) + dronabinol (5mg), on laboratory measures of anxiety (including a social stress test) in participants (n=24) with high, subclinical baseline anxiety.
Translation to the clinic:
• Collaborate with clinicians
• Conduct public & patient involvement (PPI) in people with anxiety
• Results will inform a clinical trial application
Techniques: meta-analysis, longitudinal data analysis, multilevel modelling, RStudio, randomised controlled trial, psychopharmacology