Effects of nabilone, a synthetic cannabinoid, on postoperative pain.
OBJECTIVE
Cannabinoids have been shown to have analgesic properties in animal studies, but a potential role for these drugs in acute pain management has not been established. It was hypothesized that nabilone, an oral cannabinoid synthetic tetrahydrocannabinol analogue, decreases morphine consumption, pain scores, nausea and vomiting following major surgery.


METHODS
A double-blind, randomized, placebo-controlled, parallel-group pilot trial compared the effects of two different doses, 1 mg (n = 11) and 2 mg (n = 9) of nabilone, ketoprofen 50 mg (n = 11) or placebo (n = 10), given at eight-hour intervals for 24 hr. Outcomes included morphine consumption, pain scores and emesis after major surgery. Secondary outcomes included patient tolerability of the study medication.


RESULTS
Forty-one patients (mean age 52 +/- 2 yr) undergoing gynecologic (46%), orthopedic (44%), or other (10%) surgery were recruited. Cumulative 24-hr morphine consumption was not different between the four groups, but pain scores at rest and on movement were significantly higher in the 2 mg nabilone group compared to the other groups. There were no significant differences between groups with respect to episodes of nausea and vomiting, quality of sleep, sedation, euphoria, pruritus, or the number and severity of adverse events. No serious adverse event was recorded.


CONCLUSIONS
Contrary to the main hypothesis, high dose nabilone in the presence of morphine patient controlled analgesia is associated with an increase in pain scores in patients undergoing major surgery.
Beaulieu
Pierre
P
Department of Anesthesiology, Faculty of Medicine, Université de Montréal, Québec, Canada. pierre.beaulieu@umontreal.ca
D000293:Adolescent; D000328:Adult; D000368:Aged; D016058:Analgesia, Patient-Controlled; D000700:Analgesics / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects / Q000627:therapeutic use; D004311:Double-Blind Method; D013759:Dronabinol / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D013509:Gynecologic Surgical Procedures; D006801:Humans; D007660:Ketoprofen / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D009294:Narcotics / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D019637:Orthopedic Procedures; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*; D017060:Patient Satisfaction; D010865:Pilot Projects; D010919:Placebos; D020250:Postoperative Nausea and Vomiting / Q000209:etiology; D012890:Sleep / Q000187:drug effects; D016896:Treatment Outcome
D000700:Analgesics; D000894:Anti-Inflammatory Agents, Non-Steroidal; D009294:Narcotics; D010919:Placebos; C011941:nabilone; D009020:Morphine; D013759:Dronabinol; D007660:Ketoprofen