Cannabinoids as a Potential Alternative to Opioids in the Management of Various Pain Subtypes: Benefits, Limitations, and Risks

Cannabinoids in neuropathic pain treatment: pharmacological insights and clinical outcomes from recent trials

Neuropathic pain, a complex and often devastating condition, poses significant challenges for its effective management. Despite promising research on various cannabis formulations and delivery methods for neuropathic pain, significant gaps remain in our knowledge. While inhaled cannabis shows analgesic effects and alternative delivery methods may improve bioavailability, oral formulations have yielded mixed results, often limited by small sample sizes and placebo effects. Therefore, further research is essential to optimize cannabis formulations, identify responder profiles to tailor treatments effectively, and, most critically, confirm the long-term safety and efficacy of cannabis-based therapies in managing NP. This review article aims to provide a comprehensive analysis of the therapeutic potential of cannabis-based medicines, with a particular focus on cannabinoids. This review, though not systematic, examines 11 clinical studies, specifically Randomised Clinical Trials) published from 2014 to 2024, highlighting the efficacy of numerous cannabis formulations, in alleviating neuropathic pain. Key findings show that cannabinoids can reduce pain perception, improve patient quality of life, and mitigate other symptoms associated with neuropathic pain. The synergistic effects of tetrahydrocannabinol and cannabidiol are discussed, emphasizing their ability to enhance analgesic effects, while potentially reducing the psychoactive side effects of tetrahydrocannabinol. This review emphasizes the importance of the personalized approach to improve therapeutic outcomes. Limitations of the existing research focusing on cannabis for neuropathic pain are limited by heterogeneity, lack of standardization, small sample sizes, and reliance on subjective outcomes, impacting the reliability and generalizability of findings. However, this exhaustive review aims to inform clinicians and researchers about the evolving role of cannabis in contemporary pain management strategies, illustrating the diverse pharmacological profiles of cannabinoids and their potential as adjunct therapies for neuropathic pain management.

Biochemical strategies for opioid-sparing pain management in the operating room

The opioid epidemic has highlighted the increasing need for alternative pain relievers in surgical settings. This review explores non-opioid approaches for managing pain in the ever-changing operating room. The review examines the molecular basis of pain perception, with a focus on receptor-targeted treatments that offer effectiveness without the risks associated with opioids. Despite the demonstrated benefits and improved side effect profiles, our literature analysis reveals the challenges that hinder the integration of innovative pain relievers. We explore the potential of neuroimmune modulators, peptide disruptors, and new neurotransmitter analogs in the quest for effective pain relief, paving the way for a future of anesthesia without opioids.

Cannabis use and illicit opioid cessation among people who use drugs living with chronic pain

INTRODUCTION

Amidst the opioid overdose crisis, there is interest in cannabis use for pain management and harm reduction. We investigated the relationship between cannabis use and cessation of unregulated opioid use among people who use drugs (PWUD) living with chronic pain.

METHOD

Data for analyses were collected from three prospective cohort studies in Vancouver, Canada. All cohort participants who completed at least two study visits and reported both pain and unregulated opioid use in the past 6 months were included in the present study. We analysed the association between cannabis use frequency and opioid cessation rates using extended Cox regression models with time-updated covariates.

RESULTS

Between June 2014 and May 2022, 2340 PWUD were initially recruited and of those 1242 PWUD reported chronic pain, use of unregulated opioids and completed at least two follow-up visits. Of these 1242 participants, 764 experienced a cessation event over 1038.2 person-years resulting in a cessation rate of 28.5 per 100 person-years (95% confidence interval [CI] 25.4-31.9). Daily cannabis use was positively associated with opioid cessation (adjusted hazard ratio 1.40, 95% CI 1.08-1.81; p = 0.011). In the sex-stratified sub-analyses, daily cannabis use was significantly associated with increased rates of opioid cessation among males (adjusted hazard ratio 1.50, 95% CI 1.09-2.08; p = 0.014).

DISCUSSION AND CONCLUSIONS

Participants reporting daily cannabis use exhibited higher rates of cessation compared to less frequent users or non-users. Observed sex-specific differences in cannabis use and opioid cessation suggest potential differences in cannabis use behaviours and effects. Our findings add to the growing evidence supporting the potential benefits of cannabis use among PWUD, underlining the need for further research.

Associations of discomfort intolerance, discomfort avoidance, and cannabis and alcohol use among persons with chronic pain receiving prescription buprenorphine for opioid use disorder

BACKGROUND

Chronic pain and non-prescribed substance use are associated with lower retention in opioid use disorder (OUD) treatment. We examined the associations of perceived capacity to tolerate uncomfortable physical sensations (discomfort intolerance and discomfort avoidance) and cannabis and alcohol use among persons with chronic pain receiving prescription buprenorphine for OUD.

METHODS

This study utilizes baseline data from 163 persons with chronic pain receiving prescription buprenorphine for OUD enrolled in the Treating Opioid use, Persistent Pain, and Sadness (TOPPS) intervention trial. We used negative-binomial regression models, adjusted for age, education, gender, race/ethnicity, pain interference, depression, generalized anxiety disorder, and average cigarettes smoked/day to estimate the associations of discomfort tolerance and discomfort avoidance with frequency of cannabis and alcohol use.

RESULTS

Participants (n=163) were on average 45 years old (standard deviation=10.6) and predominantly White (86 %, n=141). Forty-one percent (n=66) used cannabis and 24 % (n=30) used alcohol use in the past 30 days. In adjusted models, discomfort intolerance was positively associated with days of cannabis use (IRR = 1.11, p =.016) and days of alcohol use (IRR = 1.14, p =.022). Discomfort avoidance was not associated with cannabis or alcohol use.

CONCLUSION

Individuals with chronic pain receiving prescribed buprenorphine for treatment of OUD with lower tolerance for physical discomfort may augment pain management with cannabis and alcohol. Given the intersections between substance use and retention in care for OUD, future work should extend this preliminary work by exploring these relationships over time and in experimental settings. Clinical Trial # NCT03698669.

Medical Misinformation and Quality of Public Video Content on Cannabis for Chronic Pain Management: A Cross-Sectional Analysis of the YouTube Platform

Background

As cannabis legalization expands nationally and globally, its use for chronic pain increases, prompting people to seek information on social media platforms like YouTube. This study evaluates the accuracy and quality of information of popular YouTube videos on cannabis for chronic pain.

Methods

Using search terms related to cannabis for pain, the top 66 videos by view count were selected. Each video was classified as useful, misleading, or neither. The quality and reliability of each video were assessed using the modified DISCERN, mDISCERN, score and the Global Quality Scale, GQS. The video characteristics, usefulness classification, mDISCERN scores, and GQS scores were summarized. Continuous and categorical outcomes were compared using t-test and chi-square, respectively.

Results

Of the 66 videos, 22.73% (n=15) were classified as useful, and 77.27% (n=51) were classified as neither. Of useful videos, 40.00% (n=6) were uploaded by physicians, 40.00% (n=6) were uploaded by corporations, and 6.67% (n=1) were uploaded by an independent user. Of videos classified as neither useful nor misleading, news sources uploaded 27.45% (n=14) of these videos (P=0.02). Physicians uploaded 37.50% (n = 18) of videos with a GQS score ≥3 (P=0.04), while independent users uploaded significantly more videos with a mDISCERN score <3 (22.20%, P=0.02). Useful videos had a mean GQS of 4.00 ± 0.65 compared to a mean GQS of 2.76 ± 0.86 for videos deemed neither (P<0.0001).

Conclusion

This study suggests a moderate quality of YouTube content on cannabis use for chronic pain. Given cannabis's growing popularity and potential for misinformation on popular social media platforms, healthcare professionals and organizations should consider uploading educational videos on this topic on YouTube.

"It frees your body from that pain thought": A mixed-methods exploration of patterns, contexts, and experiences of cannabis use for pain in rural communities

U.S. adults increasingly report using cannabis to manage chronic pain and rural areas have inadequate comprehensive pain management. Using mixed methods, we aimed to understand how and why some rural adults use cannabis for pain, including within the context of co-use with opioids. Participants (N = 14, Oklahoma) were rural-dwelling adults who used tobacco and ≥1 other substance, including cannabis and opioids, ≥3 days per week. Participants completed 14 days of ecological momentary assessment (EMA) regarding substance use and subsequent in-depth interviews discussing maps of their substance use reports. Half (7/14) described cannabis use for chronic pain, and most of these (85%) reported use on ≥75% of EMA days. The most frequently reported cannabis use motive was therapeutic/medicinal (90% of use reports). Most reports were of combusted cannabis (88% of use reports) at home (99% of use reports). Same-day use of cannabis and opioids was relatively common (45% of daily surveys), but seemingly not within close temporal proximity. Interview narratives characterized cannabis as modifying pain-adjacent factors (eg, thoughts), not eliminating pain itself. They recounted using a repertoire of substances to manage different pain dimensions (eg, intensity, quality) and balance perceived trade-offs of different substances. Participants described high medical cannabis access, low pain specialist access, and most physicians as unwilling to discuss cannabis for pain. The findings suggest that rural-dwelling patients could benefit from increased access to comprehensive pain management, having cannabis addressed within pain management provider discussions, and that risks and benefits of cannabis use for pain must be better established. PERSPECTIVE: This study used a geographically explicit EMA mixed method to gather rich, intensive pilot data on cannabis use and co-use for chronic pain in rural Oklahoma. It provides unique insights to inform future research on cannabis use among a vulnerable and understudied subgroup of adults with pain-rural residents.

Endocannabinoid system and phytocannabinoids in the main species of veterinary interest: a comparative review

Since the discovery of the endocannabinoid system and due to the empirical evidence of the therapeutic effects on several illnesses both in humans and animals that follow the administration of exogenous cannabinoids (i.e., phytocannabinoids), numerous studies have been conducted. These investigations aimed to identify the expression and distribution of cannabinoid receptors in healthy and pathologic organs and tissues of different animal species and to define the interactions of phytocannabinoids with these receptors. In the last decade, pharmacokinetics, efficacy and tolerability of many Cannabis derivatives formulations, mainly containing cannabidiol, in the main species of veterinary interest, have been also investigated. This manuscript summarizes the findings reported by the scientific studies published so far on the molecular mode of action of the main phytocannabinoids, the localization of cannabinoid receptors in organs and tissues, as well as the pharmacokinetics, efficacy and tolerability of Cannabis derivatives in dogs, cats, horses and other species of veterinary interest. A deep knowledge of these issues is crucial for the use of phytocannabinoids for therapeutic purposes in animal species.

Neuropharmacology of Neuropathic Pain: A Systematic Review

Neuropathic pain, a debilitating condition, remains challenging to manage effectively. An insight into neuropharmacological mechanisms is critical for optimizing treatment strategies. This systematic review aims to evaluate the role of neuropharmacological agents based on their efficacy, involved neurotransmitters, and receptors. A manual literature search was undertaken in PubMed including Medline, Cochrane Library, Google Scholar, Plos One, Science Direct, and clinicaltrials.gov from 2013 until 2023. Out of the 13 included studies, seven evaluated the role of gabapentinoids. Two main drugs from this group, gabapentin and pregabalin, function by binding voltage-gated calcium channels, lowering neuronal hyperexcitability and pain signal transmission, thereby relieving neuropathic pain. Four of the pooled studies reported the use of tricyclic antidepressants (TCAs) including amitriptyline and nortriptyline which work by blocking the reuptake of norepinephrine and serotonin, their increased concentration is thought to be central to their analgesic effect. Three articles assessed the use of serotonin-norepinephrine reuptake inhibitors (SNRIs) and reported them as effective as the TCAs in managing neuropathic pain. They work by augmenting serotonin and norepinephrine. Three studies focused on the use of selective serotonin reuptake inhibitors (SSRIs), modulating their effect by increasing serotonin levels; however, they were reported as not a highly effective treatment option for neuropathic pain. One of the studies outlined the use of cannabinoids for neuropathic pain by binding to cannabinoid receptors with only mild adverse effects. It is concluded that gabapentinoids, TCAs, and SNRIs were reported as the most effective therapy for neuropathic pain; however, for trigeminal neuralgia, anticonvulsants like carbamazepine were considered the most effective. Opioids were considered second-line drugs for neuropathic pain as they come with adverse effects and a risk of dependence. Ongoing research is exploring novel drugs like ion channels and agents modulating pain pathways for neuropathic pain management. Our review hopes to inspire further research into patient stratification by their physiology, aiding quicker and more accurate management of neuropathic pain while minimizing inadvertent side effects.

The association of perceived cannabis risks and benefits with cannabis use since cancer diagnosis

BACKGROUND

Many patients with cancer use cannabis to help alleviate untreated cancer symptoms and side effects.

METHODS

We examined associations of perceived benefits and risks and postdiagnosis cannabis use in a weighted sample of adult cancer survivors through a 1-time survey. Fifteen perceived cannabis use benefits and 19 perceived risks were operationalized as both summary scores and report of any benefits or risks. Survey-weighted logistic regression provided covariate-adjusted odds of postdiagnosis cannabis use for each benefit-risk measure.

RESULTS

Among the weighted population of 3785 survivors (mean [SD] age = 62.2 [13.5] years), one-third used cannabis after diagnosis. Perceiving any benefits increased the odds of postdiagnosis cannabis use more than 500%, and perceiving any risks lowered the odds by 59%. Each SD increase in endorsed benefits doubled the odds of postdiagnosis cannabis use, while each SD increase in endorsed risks reduced the odds by 36%.

CONCLUSION

An accurate understanding of benefits and risks is critical for informed decision making.

Cannabidiol and pain

Chronic pain presents significant personal, psychological, and socioeconomic hurdles, impacting over 30% of adults worldwide and substantially contributing to disability. Unfortunately, current pharmacotherapy often proves inadequate, leaving fewer than 70% of patients with relief. This shortfall has sparked a drive to seek alternative treatments offering superior safety and efficacy profiles. Cannabinoid-based pharmaceuticals, notably cannabidiol (CBD), hold promise in pain management, driven by their natural origins, versatility, and reduced risk of addiction. As we navigate the opioid crisis, ongoing research plunges into CBD's therapeutic potential, buoyed by animal studies revealing its pain-relieving prowess through various system tweaks. However, the efficacy of cannabis in chronic pain management remains a contentious and stigmatized issue. The International Association for the Study of Pain (IASP) presently refrains from endorsing cannabinoid use for pain relief. Nevertheless, evidence indicates their potential in alleviating cancer-related, neuropathic, arthritis, and musculoskeletal pain, necessitating further investigation. Crucially, our comprehension of CBD's role in pain management is a journey still unfolding, with animal studies illustrating its analgesic effects through interactions with the endocannabinoid, inflammatory, and nociceptive systems. As the plot thickens, it's clear: the saga of chronic pain and CBD's potential offers a compelling narrative ripe for further exploration and understanding.

Cannabinoids' Role in Modulating Central and Peripheral Immunity in Neurodegenerative Diseases

Cannabinoids (the endocannabinoids, the synthetic cannabinoids, and the phytocannabinoids) are well known for their various pharmacological properties, including neuroprotective and anti-inflammatory features, which are fundamentally important for the treatment of neurodegenerative diseases. The aging of the global population is causing an increase in these diseases that require the development of effective drugs to be even more urgent. Taking into account the unavailability of effective drugs for neurodegenerative diseases, it seems appropriate to consider the role of cannabinoids in the treatment of these diseases. To our knowledge, few reviews are devoted to cannabinoids' impact on modulating central and peripheral immunity in neurodegenerative diseases. The objective of this review is to provide the best possible information about the cannabinoid receptors and immuno-modulation features, peripheral immune modulation by cannabinoids, cannabinoid-based therapies for the treatment of neurological disorders, and the future development prospects of making cannabinoids versatile tools in the pursuit of effective drugs.

Perioperative Cannabinoids Significantly Reduce Postoperative Opioid Requirements in Patients Undergoing Coronary Artery Bypass Graft Surgery

Background Opioids, commonly used to control pain associated with surgery, are known to prolong the duration of mechanical ventilation and length of hospital stay. A wide range of adjunctive strategies are currently utilized to reduce postoperative pain, such as local and regional nerve blocks, nerve cryoablation, and adjunctive medications. We hypothesized that dronabinol (a synthetic cannabinoid) in conjunction with standard opioid pain management will reduce opioid requirements to manage postoperative pain. Methods Sixty-eight patients who underwent isolated first-time coronary artery bypass graft surgery were randomized to either the control group, who received only standard opioid-based analgesia, or the dronabinol group, who received dronabinol (a synthetic cannabinoid) in addition to standard opioid-based analgesia. Dronabinol was given in the preoperative unit, before extubation in the ICU, and after extubation on the first postoperative day. Preoperative, intraoperative, and postoperative parameters were compared under an IRB-approved protocol. The primary endpoints were the postoperative opioid requirement, duration of mechanical ventilation, and ICU length of stay, and the secondary endpoints were the duration of inotropic support needed, left ventricular ejection fraction (LVEF), and the change in LVEF. This study was undertaken at Northwest Medical Center, Tucson, AZ, USA. Results Sixty-eight patients were randomized to either the control group (n = 37) or the dronabinol group (n = 31). Groups were similar in terms of demographic features and comorbidities. The total postoperative opioid requirement was significantly lower in the dronabinol group [39.62 vs 23.68 morphine milligram equivalents (MMEs), p = 0.0037], representing a 40% reduction. Duration of mechanical ventilation (7.03 vs 6.03h, p = 0.5004), ICU length of stay (71.43 vs 63.77h, p = 0.4227), and inotropic support requirement (0.6757 vs 0.6129 days, p = 0.7333) were similar in the control and the dronabinol groups. However, there was a trend towards lower durations in each endpoint in the dronabinol group. Interestingly, a significantly better preoperative to postoperative LVEF change was observed in the dronabinol group (3.51% vs 6.45%, p = 0.0451). Conclusions Our study found a 40% reduction in opioid use and a significantly greater improvement in LVEF in patients treated with adjunctive dronabinol. Mechanical ventilation duration, ICU length of stay, and inotropic support requirement tended to be lower in the dronabinol group, though did not reach statistical significance. The results of this study, although limited by sample size, are very encouraging and validate our ongoing investigation.

Significant use of non-evidence-based therapeutics in a cohort of Australian fibromyalgia patients

BACKGROUND

Fibromyalgia is a common condition characterised by chronic widespread musculoskeletal pain and central sensitivity features. Appropriate management requires a multidisciplinary approach prioritising non-pharmacological strategies. Evidence-based fibromyalgia medications are not always easily available, effective or tolerated.

AIM

To characterise actual medication usage in Australian fibromyalgia patients.

METHODS

Demographic and clinical data, including medication use information, were gathered by chart review from patients attending the Monash Fibromyalgia Clinic between January 2019 and June 2022. Eligible patients were invited to complete an anonymous questionnaire between June and August 2022 to assess current therapeutic use. The questionnaire assessed fibromyalgia clinical features by using the Revised Fibromyalgia Impact Questionnaire and the 2016 modified American College of Rheumatology Fibromyalgia criteria.

RESULTS

The chart review included 474 patients, and 108 participants completed the questionnaire. Most chart review (78.7%) and questionnaire participants (85.2%) reported using at least one medication for their fibromyalgia. 48.5% of chart review patients and 58.3% of questionnaire participants reported using at least one evidence-based medication, usually amitriptyline, duloxetine or pregabalin. However, the most common individual medications for questionnaire participants were non-steroidal anti-inflammatory drugs (48.2%), paracetamol (59.3%) and opioids (34.3%), with most opioids being typical opioids. Among questionnaire participants, 14.8% reported using cannabinoids, and 70.4% reported using at least one supplement, vitamin or herbal/naturopathic preparation. Not all medication or substance use was recorded during clinic appointments.

CONCLUSION

Fibromyalgia patients engage in various pharmacotherapeutic strategies that are not always evidence-based or disclosed to their treating clinicians.

Cannabis use in the intensive care setting: A scoping review

PURPOSE

Cannabis is the most used recreational drug worldwide, and is increasingly used for medicinal purposes, however little is known about its impact on patients in intensive care units (ICU). Our objective was to identify key themes in the literature surrounding cannabis in the ICU and identify future research priorities.

METHODS

Four databases were systematically searched for literature investigating the impact of cannabis, and evidence for its therapeutic use, in adult ICU patients.

RESULTS

Of 2589 articles screened, 22 articles were included for analysis. Cannabis-associated admissions were primarily related to an outbreak of vaping associated lung injury, and synthetic cannabinoid toxicity. Studies on the impact of cannabis use on outcomes were mostly limited to trauma and burns populations, with an inconsistent mortality benefit, and a trend towards increased pain scores and analgesic requirements found. There is minimal research on its therapeutic uses in ICU, with two trials investigating the use of a synthetic cannabinoid in patients with severe traumatic brain injury, with ultimately no significant effect on intracranial pressure found.

CONCLUSIONS

There is a paucity of studies investigating the impact of cannabinoids or their therapeutic uses in critically ill patients, with further research in this area needed.

Therapeutic Potential of Minor Cannabinoids in Dermatological Diseases-A Synthetic Review

Dermatological diseases pose a significant burden on the quality of life of individuals and can be challenging to treat effectively. In this aspect, cannabinoids are gaining increasing importance due to their therapeutic potential in various disease entities including skin diseases. In this synthetic review, we comprehensively analyzed the existing literature in the field of potential dermatological applications of a lesser-known subgroup of cannabinoids, the so-called minor cannabinoids, such as cannabidivarin (CBDV), cannabidiforol (CBDP), cannabichromene (CBC), tetrahydrocannabivarin (THCV), cannabigerolic acid (CBGA), cannabigerol (CBG), cannabielsoin (CBE), cannabimovone (CBM) or cannabinol (CBN), while drawing attention to their unique pharmacological properties. We systematically searched the available databases for relevant studies and analyzed the data to provide an overview of current thematic knowledge. We looked through the full-text, bibliographic and factographic databases, especially Scopus, Web of Science, PubMed, Polish Scientific Journals Database, and selected the most relevant papers. Our review highlights that minor cannabinoids exhibit diverse pharmacological activities, including anti-inflammatory, analgesic, antimicrobial, and anti-itch properties. Several studies have reported their efficacy in mitigating symptoms associated with dermatological diseases such as psoriasis, eczema, acne, and pruritus. Furthermore, minor cannabinoids have shown potential in regulating sebum production, a crucial factor in acne pathogenesis. The findings of this review suggest that minor cannabinoids hold therapeutic promise in the management of dermatological diseases. Further preclinical and clinical investigations are warranted to elucidate their mechanisms of action, determine optimal dosage regimens, and assess long-term safety profiles. Incorporating minor cannabinoids into dermatological therapies could potentially offer novel treatment options of patients and improve their overall well-being.

Deciphering Complex Interactions in Bioactive Lipid Signaling

Lipids are usually viewed as metabolic fuel and structural membrane components. Yet, in recent years, different families of lipids able to act as authentic messengers between cells and/or intracellularly have been discovered. Such lipid signals have been shown to exert their biological activity via specific receptors that, by triggering distinct signal transduction pathways, regulate manifold pathophysiological processes in our body. Here, endogenous bioactive lipids produced from arachidonic acid (AA) and other poly-unsaturated fatty acids will be presented, in order to put into better perspective the relevance of their mutual interactions for health and disease conditions. To this end, metabolism and signal transduction pathways of classical eicosanoids, endocannabinoids and specialized pro-resolving mediators will be described, and the intersections and commonalities of their metabolic enzymes and binding receptors will be discussed. Moreover, the interactions of AA-derived signals with other bioactive lipids such as shingosine-1-phosphate and steroid hormones will be addressed.