Cannabis‐Based Oil for Pain and Other Non‐Motor Symptoms in Parkinson's Disease: A Randomized Controlled Trial

Background There is a lack of treatments for non‐motor symptoms (NMS) in Parkinson's disease (PD). Objective To assess the safety and effectiveness of an oral Cannabis sativa L. extract on pain and other NMS of PD. Methods This phase II, randomized, placebo‐controlled trial evaluated a formulation containing cannabidiol (CBD; 96 mg/ml) and Δ9‐tetrahydrocannabinol (THC; 2.1 mg/ml) in PD patients with chronic pain over 9 weeks. The final daily dosage was 43.88 mg CBD and 0.96 mg THC. The primary outcome was the between‐group difference in PD‐Pain Classification System (PCS) scores at final visit. Results We enrolled 101 participants, and 87 completed the study. No significant differences were observed between the CBD/THC and placebo groups in PD‐PCS scores ( P = 0.757) or in other non‐motor scales. No serious adverse events were reported. Conclusion A cannabis oil formulation did not improve pain or other NMS compared with placebo in people with PD.