Short-Term Effects of Medicinal Cannabis Therapy on Spasticity in Multiple Sclerosis

The purpose of this study is to determine whether or not smoked marijuana improves spasticity in patients with multiple sclerosis.

Studies of cannabinoids for spasticity in MS have had mixed results but clinical studies have been small, generally not properly controlled, with results controversial, and difficult to interpret. Recently, investigators in the UK and US tested the ability of cannabinoids to control spasticity and tremor symptoms of the MS-like disease, experimental allergic encephalomyelitis, in mice (Baker et al, 2000). The authors found that four different cannabinoids quantitatively ameliorated both tremor and spasticity in diseased mice; thus providing rationale for patients' reports of the therapeutic effects of cannabis in the control of their MS symptoms.

The present study will be a randomized, placebo-controlled, crossover design of 30 patients who will be assessed before and after treatment for 3 consecutive days (Phase I), undergo washout-out for a total of 11 days, and then cross over to either the placebo or active treatment phase (Phase II), depending on what they received during Phase I. At each study visit, patients will utilize a controlled puff procedure to help ensure stable intake (Levin et al, 1989).

Comparisons: A single dose of 4% THC marijuana cigarette each day for 3 days will be compared to a placebo administered under the same dosing conditions for the relief of spasticity, drug tolerability, and changes in global functioning and quality of life indices.