The effects of nabilone on sleep in fibromyalgia: results of a randomized controlled trial.
BACKGROUND
Sleep disorders affect many patients with chronic pain conditions. Cannabis has been reported by several patient populations to help sleep. We evaluated the safety and efficacy of nabilone, a synthetic cannabinoid, on sleep disturbance in fibromyalgia (FM), a disease characterized by widespread chronic pain and insomnia.


METHODS
We conducted a randomized, double-blind, active-control, equivalency crossover trial to compare nabilone (0.5-1.0 mg before bedtime) to amitriptyline (10-20 mg before bedtime) in patients with FM with chronic insomnia. Subjects received each drug for 2 wk with a 2-wk washout period. The primary outcome was sleep quality, measured by the Insomnia Severity Index and the Leeds Sleep Evaluation Questionnaire. Secondary outcomes included pain, mood, quality of life, and adverse events (AEs).


RESULTS
Thirty-one subjects were enrolled and 29 completed the trial (26 women, mean age 49.5 yr). Although sleep was improved by both amitriptyline and nabilone, nabilone was superior to amitriptyline (Insomnia Severity Index difference = 3.2; 95% confidence interval = 1.2-5.3). Nabilone was marginally better on the restfulness (Leeds Sleep Evaluation Questionnaire difference = 0.5 [0.0-1.0]) but not on wakefulness (difference = 0.3 [-0.2 to 0.8]). No effects on pain, mood, or quality of life were observed. AEs were mostly mild to moderate and were more frequent with nabilone. The most common AEs for nabilone were dizziness, nausea, and dry mouth.


CONCLUSIONS
Nabilone is effective in improving sleep in patients with FM and is well tolerated. Low-dose nabilone given once daily at bedtime may be considered as an alternative to amitriptyline. Longer trials are needed to determine the duration of effect and to characterize long-term safety.
Ware
Mark A
MA
Pain Clinic, McGill University Health Centre, Montreal, Quebec, Canada. mark.ware@muhc.mcgill.c
Fitzcharles
Mary-Ann
MA
Joseph
Lawrence
L
Shir
Yoram
Y
D000328:Adult; D000368:Aged; D000639:Amitriptyline / Q000627:therapeutic use; D014151:Anti-Anxiety Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000928:Antidepressive Agents; D018592:Cross-Over Studies; D004311:Double-Blind Method; D013759:Dronabinol / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D005356:Fibromyalgia / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D017060:Patient Satisfaction; D012890:Sleep; D007319:Sleep Initiation and Maintenance Disorders / Q000188:drug therapy* / Q000209:etiology
D014151:Anti-Anxiety Agents; D000928:Antidepressive Agents; D000639:Amitriptyline; C011941:nabilone; D013759:Dronabinol