Cannabis in Parkinson's Disease - the patient's perspective versus clinical trials: a systematic literature review.

Cannabis and cannabinoids are often considered in the treatment of Parkinson's Disease (PD). The purpose of this paper was to perform a systematic review of the available data on cannabis treatment. We aimed to assess randomised trials as well as surveys among patients. We identified 569 papers on PD and cannabinoid treatment. Of these, there were only seven papers featuring randomised trials on the effects of different cannabinoids on PD. The results of these trials did not support the efficacy of cannabinoids in the treatment of motor signs of PD. Based on the available data, we conclude that there is currently insufficient data to support the administration of cannabinoids to PD patients. Larger, randomised studies of cannabis use in PD should be conducted.