Effects of nabilone, a synthetic cannabinoid, on postoperative pain

Abstract

Purpose: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.

Cannabinoids, Endocannabinoids, and Related Analogs in Inflammation

“…Correct dosing will also be important. Indeed, a dose of nabilone of 2 mg three times daily was associated with an increase in pain scores in a trial of postoperative pain (43).…”

Dissociable Effects of the Cannabinoid Receptor Agonists Δ9-Tetrahydrocannabinol and CP55940 on Pain-Stimulated Versus Pain-Depressed Behavior in Rats

“…In view of these attributes, we have argued that assays of pain-depressed behavior may complement conventional assays of pain-stimulated behavior and increase the predictive validity of preclinical candidate analgesic assessment (Negus et al, , 2010a. Given the poor efficacy of THC and other cannabinoid receptor agonists to treat acute pain in humans (Raft et al, 1977;Buggy et al, 2003;Naef et al, 2003;Beaulieu, 2006;Kraft et al, 2008;Klooker et al, 2011) we predicted that THC and CP55940 would not produce antinociception in assays of acute pain-depressed behavior in rats despite the apparent efficacy of these drugs in standard assays of pain-stimulated behavior.…”

A User’s Guide to Cannabinoid Therapies in Oncology

“…Early studies using dronabinol, nabilone, and levonantradol demonstrated benefit, but their methodologies were not as rigorous as in more recent trials, and so the benefits might have been overestimated 36 . The few trials using cannabinoids in acute pain have shown essentially no benefit, and present recommendations are against cannabinoid use in the postoperative setting [37][38][39] .…”