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. © 2026 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.