John Stauffer
University of Florida
Co-Authors: Paul A Borsa, Joshua A Crow, Mark D Bishop, Robert L Cook
University of Florida
Context: Current research has shown evidence that phyto-cannabinoids may have a promising therapeutic potential in a variety of physical ailments, and cannabidiol (CBD) is of particular interest due to its positive safety profile, non-intoxicating effects, and widespread capabilities in a number of musculoskeletal diseases. Very little is known about CBD and how it functions in the body from both an efficacy and mechanistic perspective, especially in humans. Our objective was to investigate the therapeutic impact of a controlled short-term trial of CBD use for reducing symptomatic response and facilitating recovery following induced muscle injury.
Methods: A double-blind, randomized, two-arm study design was used with participants randomly assigned to either an active CBD dose group or a placebo control group. Participants completed a 15-day study trial which included baseline testing, intervention (CBD/placebo dosing regimen), and follow-up assessments. Participants self-administered the investigational product (CBD or placebo) under the tongue (sublingual) twice daily for 15 days. Daily dosage of CBD was 67mg. An experimental injury protocol for the quadriceps muscle group on day 10 induced pain and functional disability in otherwise healthy men (n=9) and women (n=20) [age: 20.1 yrs, weight: 64.2±8.5kg, height: 169±5.3cm]. Follow-up measurements occurred on days 11 through day 15 (24 to 96-hours post-exercise).
Results: There were no reports from participants of side effects or treatment-emergent adverse events from consuming the CBD or placebo (Pla). This indicates that the product was safe to use and well tolerated by the participants. The design was statistically underpowered (p-values > 0.05), but trends were observed for reduced symptomatic response and improved recovery. Symptoms and functional deficits were most pronounced 24 to 48 hrs. post-exercise and were least pronounced by day 5. Pain was reported using a numerical rating scale (0 – 100) with 0 indicating ‘no pain’ and 100 indicating ‘worst pain imaginable’. A trend was observed for CBD users to report less pain at rest (PAR) and movement-evoked pain (MEP) after exercise especially at 48-hrs post-exercise [PAR (CBD = 52/100 v. Pla 63/100)] and [MEP (CBD = 23/100 v. Pla 38/100)]. The CBD group also reported that they were more functional (CBD = 68/100 than placebo (61/100) at day 2 post-exercise.
Conclusions: CBD administered sublingually demonstrated a favorable safety profile and showed promise in reducing symptoms associated with strenuous exercise. Clinical studies using larger sample sizes are needed to confirm the reported trends in controlling pain and function post-exercise.