Tomer Goldberg, Yonatan Redlich, David Yogev, Tsvia Fay-Karmon, Sharon Hassin-Baer, Saar Anis


May 4,  2023



Whole-plant medical cannabis (MC) products are widely used for controlling symptoms associated with Parkinson’s disease (PD). Despite its widespread use, few studies have investigated the long-term impact of MC on the progression of PD or its safety profile. This study examined the effects of MC on PD in a real-life setting.


A retrospective case-control study of 152 idiopathic PD patients (mean age 69.1 ± 9.0 years), followed at the Sheba Medical Center Movement Disorders Institute (SMDI) from 2008 to 2022 was conducted. Seventy-six patients who used licensed whole-plant medical cannabis (MC) for at least a year were compared to a matched group who did not receive MC in terms of their Levodopa Equivalent Daily Dose (LEDD), Hoehn and Yahr (H&Y) stage, and cognitive, depressive, and psychotic symptoms.


The median monthly dose of MC was 20 g (IQR: 20–30), with a median Tetrahydrocannabinol (THC) percentage of 10 (IQR: 9.5–14.15) and a median Cannabidiol (CBD) percentage of 4 (IQR: 2–10). There were no significant differences between the MC and the control groups for LEDD or H&Y stage progression (p = 0.90, 0.77, respectively). A Kaplan-Meier analysis showed no evidence of relative worsening of psychotic, depressive, or cognitive symptoms reported by patients to their treating physicians over time in the MC group (p = 0.16–0.50).


Over the 1–3 years of follow-ups, the MC treatment regimens appeared to be safe. MC did not exacerbate neuropsychiatric symptoms and had no detrimental effects on disease progression.

DOI: 10.1016/j.parkreldis.2023.105406


Goldberg, T., Redlich, Y., Yogev, D., Fay-Karmon, T., Hassin-Baer, S., & Anis, S. (2023). Long-term safety of medical Cannabis in Parkinson’s disease: A retrospective case-control study. Parkinsonism & Related Disorders, 105406.