Johnson, J.R., Burnell-Nugent, M., Lossignol, D., Ganae-Motan, E.D., Potts, R., & Fallon, M.T. (2010). Multicenter, double-blind, randomized, placebo-controlled, parallel-group study of the efficacy, safety, and tolerability of THC:CBD extract and THC extract in patients with intractable cancer-related pain. Journal of Pain and Symptom Management, 39(2), 167–179.doi: 10.1016/j.jpainsymman.2009.06.008
To compare the efficacy of a tetrahydrocannabinol:cannabidiol (THC:CBD) extract, a nonopioid analgesic endocannabinoid system modulator, and a THC extract to the efficacy of placebo in relieving the pain of patients with advanced cancer; to compare the safety and tolerability of the treatments with those of placebo
Patients with cancer pain, who experienced inadequate analgesia despite chronic opioid dosing, were randomized to THC:CBD extract (n = 60 patients), THC extract (n = 58), or placebo (n = 59) for a two-week, multicenter randomized double-blind, placebo-controlled trial.
Randomized, double-blind, placebo-controlled, parallel-group study
THC:CBD may be of benefit as an adjunct to opioid when pain is not fully controlled despite chronic opioid therapy. However, this conclusion warrants further investigation; the EORTC questionnaire showed a worsening of nausea and vomiting in the THC:CBD group, compared to the placebo group. In addition, patients in this study reported a consistent impairment of cognitive function. In addition, though authors reported at least a 30% reduction in NRS from baseline in the THC:CBD group, from baseline no change occurred, across treatment groups, in median dose of opioid background medication or mean number of doses of breakthrough medication.
THC:CBD extract—a nonopioid analgesic, endocannabinoid system modulator—may be a useful adjunct in managing the pain of patients who have inadequate analgesia from chronic opioids. However, one must consider the potential side effects (i.e. nausea, vomiting, impaired cognitive functions) that may occur as a result of adding this medication.