A new systematic review and meta-analysis showed a small but significant reduction in subjective pain scores for cannabinoid treatment compared to placebo in patients experiencing acute pain.
No increase in serious adverse events suggested the safety of using cannabinoids to treat acute pain, according to the study published in Cannabis and Cannabinoid Research, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. Click here to read the full-text article free on the Cannabis and Cannabinoid Research website through April 23, 2020.
The article, “Cannabinoids in the Management of Acute Pain: A Systematic Review and Meta-analysis” was coauthored by Herman Johal, MD, MPH, PhD, McMaster University, Hamilton, Canada and colleagues from McMaster University and Northern Ontario School of Medicine, Thunder Bay.
The researchers included six trials in their study, five using oral cannabinoids, and one using intramuscular cannabinoids. They reported a significant difference in effect size between the oral and nonoral routes of administration, with intramuscular cannabinoids yielding a significant reduction in pain relative to placebo. There was no difference in effect between oral cannabinoids and placebo.
- There were five studies (7 comparisons and 622 patients) that reported on oral cannabinoids and found no significant treatment effect when compared with placebo (−0.21, 95% CI −0.64 to 0.22, i2=3%, p=0.41.
- There was one trial (4 comparisons, 56 participants) that evaluated intramuscular administration of cannabinoids and found a significant treatment effect favoring the use of cannabinoids over placebo (−2.98, 95% CI −4.09 to −1.87, i2=39%, p<0.0001).
- There were 14/374 (3.7%) serious adverse effects in the cannabinoid arms and 8/304 (2.6%) in the control group. Serious adverse effects in the treatment groups consisted of nausea (5), headache (4), sedation (3), dysphagia (1), and pharyngolaryngeal pain (1).
- Side effects in the placebo group consisted of headache (3), nausea (2), myalgia (1), pain (1), and swelling (1).
Conclusion/ “The usefulness of cannabis-derived medicines in the treatment of pain, both acute and chronic, is still vigorously debated. The meta-analysis conducted in this study reinforces the need for more rigorous studies to assess whether cannabis might be effective in the treatment of acute pain conditions,” said editor-in-chief Daniele Piomelli, PhD University of California-Irvine, School of Medicine.