title: Randomized, controlled trial of cannabis-based medicine in central pain in multiple sclerosis.
abstract: BACKGROUND
  Central pain in multiple sclerosis (MS) is common and often refractory to treatment.
  
  
  METHODS
  We conducted a single-center, 5-week (1-week run-in, 4-week treatment), randomized, double-blind, placebo-controlled, parallel-group trial in 66 patients with MS and central pain states (59 dysesthetic, seven painful spasms) of a whole-plant cannabis-based medicine (CBM), containing delta-9-tetrahydrocannabinol:cannabidiol (THC:CBD) delivered via an oromucosal spray, as adjunctive analgesic treatment. Each spray delivered 2.7 mg of THC and 2.5 of CBD, and patients could gradually self-titrate to a maximum of 48 sprays in 24 hours.
  
  
  RESULTS
  Sixty-four patients (97%) completed the trial, 34 received CBM. In week 4, the mean number of daily sprays taken of CBM (n = 32) was 9.6 (range 2 to 25, SD = 6.0) and of placebo (n = 31) was 19.1 (range 1 to 47, SD = 12.9). Pain and sleep disturbance were recorded daily on an 11-point numerical rating scale. CBM was superior to placebo in reducing the mean intensity of pain (CBM mean change -2.7, 95% CI: -3.4 to -2.0, placebo -1.4 95% CI: -2.0 to -0.8, comparison between groups, p = 0.005) and sleep disturbance (CBM mean change -2.5, 95% CI: -3.4 to -1.7, placebo -0.8, 95% CI: -1.5 to -0.1, comparison between groups, p = 0.003). CBM was generally well tolerated, although more patients on CBM than placebo reported dizziness, dry mouth, and somnolence. Cognitive side effects were limited to long-term memory storage.
  
  
  CONCLUSIONS
  Cannabis-based medicine is effective in reducing pain and sleep disturbance in patients with multiple sclerosis related central neuropathic pain and is mostly well tolerated.
authors.affiliation: Walton Centre for Neurology and Neurosurgery, University of Liverpool, Liverpool, United Kingdom. djrdjr@doctors.org.uk
authors.forename: David J
authors.initials: DJ
authors.lastname: Rog
authors.forename: Turo J
authors.initials: TJ
authors.lastname: Nurmikko
authors.forename: Tim
authors.initials: T
authors.lastname: Friede
authors.forename: Carolyn A
authors.initials: CA
authors.lastname: Young
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000700:Analgesics / Q000008:administration & dosage* / Q000009:adverse effects; D002186:Cannabinoids / Q000008:administration & dosage* / Q000009:adverse effects; D002490:Central Nervous System / Q000187:drug effects / Q000503:physiopathology; D006970:Disorders of Excessive Somnolence / Q000139:chemically induced; D004244:Dizziness / Q000139:chemically induced; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D013759:Dronabinol / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000139:chemically induced; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications*; D010147:Pain Measurement / Q000187:drug effects; D017288:Pain Threshold / Q000187:drug effects / Q000502:physiology; D010148:Intractable Pain / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D008517:Phytotherapy; D010919:Placebos; D028321:Plant Preparations / Q000008:administration & dosage* / Q000009:adverse effects; D012893:Sleep Wake Disorders / Q000188:drug therapy / Q000209:etiology; D016896:Treatment Outcome
chemical_list: D000700:Analgesics; D002186:Cannabinoids; D010919:Placebos; D028321:Plant Preparations; D013759:Dronabinol