Cannabinoid-based medications for pain
Interest in these agents may be outpacing the evidence supporting their analgesic benefits.
Other chronic pain conditions. CBM have also been studied for their usefulness in several other noncancer chronic conditions, including Crohn’s disease, inflammatory bowel disease, fibromyalgia, and other rheumatologic pain conditions.22,31,38-40 However, a solid foundation of empirical work to inform their utility for managing pain in these conditions is lacking.
CBM for cancer pain
Anecdotal evidence suggests that inhaled cannabis has promising pain-mitigating effects in patients with advanced cancer.41-43 There is a dearth of high-quality RCTs assessing the utility of CBM in patients with cancer pain.43-45 The types of CBM used and dosing strategies varied across RCTs, which makes it difficult to infer how best to treat patients with cancer pain. The agents studied included nabiximols, THC spray, and synthetic THC capsules.43-45 Although some studies have demonstrated that synthetic THC and nabiximols have potential for reducing subjective pain ratings compared with placebo,46,47 these results were inconsistent.46,48 Oromucosal nabiximols did not appear to confer any additional analgesic benefit in patients who were already prescribed opioids.31,45
The benefit of CBM for mitigating cancer pain is promising, but it remains difficult to know how to position the use of CBM in managing cancer pain. Limitations in the cancer literature include:
- the RCTs addressing CBM use for cancer pain were often brief, which raises questions about the long-term effectiveness and adverse effects of these agents
- tolerability and dosing limits encountered due to adverse effects were seldom reported43,45
- the types of cancer pain that patients had were often quite diverse. The small sample sizes and the heterogeneity of conditions included in these RCTs limit the ability to determine whether pain-mitigating effects might vary according to type of cancer-related pain.31,45
Despite these limitations, some clinical guidelines and systematic reviews have suggested that CBM have some role in addressing refractory malignant pain conditions.49
Psychiatric considerations related to CBM
As of November 2020, 36 states had legalized the use of cannabis for medical purposes, typically for painful conditions, despite the fact that empirical evidence to support their efficacy is mixed.50 In light of recent changes in both the legal and popular attitudes regarding cannabis, the implications of legalizing CBM remains to be seen. For example, some research suggests that adults with pain are vulnerable to frequent nonmedical cannabis use and/or cannabis use disorder.51 Although well-intended, the legalization of CBM use might represent society’s next misstep in the quest to address the suffering of patients with chronic pain. Some evidence shows that cannabis use and cannabis use disorders increase in states that have legalized medical marijuana.52,53 Psychiatrists will be on the front lines of addressing any potential consequences arising from the use of CBM for treating pain.
Continue to: Psychiatric disorders and CBM
