Few controlled clinical studies explored the effects of CBs on motor and nonmotor symptoms in PD patients.94–97 A small randomized, double-blind, placebo-controlled crossover trial (Class III) assessing the efficacy on LIDs of nabilone (CB1 and CB2 agonist) showed reduction of the Rush Dyskinesia Disability Scale and of total LID time.94 A small 4-week randomized double-blind crossover study (Class I) explored the effect of Cannador (oral cannabis extract: 1.25 mg CBD and 2.5 mg THC) on LIDs.95 Cannador failed to improve LIDs. The gene discussed is CNR1; the disease is Parkinson disease.