Beneficial and Adverse Effects of Cannabidiol in a Parkinson Patient with Sinemet-Induced Dystonic Dyskinesia

Stuart R. Snider and Paul Consroe, Tucson, AZ

"Neurology" 35 April 1985 (Suppl 1) p. 201 

In idiopathic dystonia, the therapeutic effect of marijuana smoking is reported to be comparable with diazepam (C.D. Marsden, in Disorders of Movement, 1981: 81). The non-psychoactive cannabis derivative, cannabidiol (CBD), also improves dystonia (Consroe and Snider, in Cannabinoids as Therapeutic Agents, in press). We report the effect of CBD on dystonia secondary to Sinemet in parkinsonism, a disorder thought to be a relative contraindication for cannabinoids (D. Moss et al, Pharmacol Biochem Behav 1981, 1984). The patient, a 42 year-old man with an 8-year history of parkinsonism, developed peak-dose dyskinesia about 4 years ago and action dystonia affecting all limbs more recently. Trohexyphenidyl and bromocriptine each produced only slight improvement. To stable optimal dosages of the three drugs, CBD was added, starting with 100 mg/d and increasing by 100 mg weekly. At 100 to 200 mg/d, there was a decrease in clinical fluctuations and in dyskinesia scores (by 30%) without a significant worsening of the parkinsonism. At 300 to 400 mg/d, there was no further improvement in the dyskinesia, and adverse effects (dizziness, increased Parkinson symptoms) appeared. CBD withdrawal resulted in 3 days of severe generalized dystonia and several weeks of increased sensitivity to Sinemet, suggestive of a "drug holiday" effect.