European Pain Federation (EFIC) position paper on appropriate use of cannabis-based medicines and medical cannabis for chronic pain management

Clinical Benefits and Safety of Medical Cannabis Products: A Narrative Review on Natural Extracts

Interest in medical cannabis and cannabis-based medicinal products (CBMPs) has increased greatly in recent years. Two cannabinoids are of principal importance; delta-9-tetrahydrocannabinol (∆9-THC), the primary psychoactive component, and also cannabidiol (CBD), considered non-intoxicating. Each has distinct mechanisms of action and different therapeutic potentials. CBMPs differ in their ∆9-THC and CBD components; predominantly ∆9-THC, balanced formulations with equivalent ∆9-THC and CBD elements, and CBD-predominant products. In this narrative review, we evaluate the published evidence for the clinical benefits of CBMPs and overall benefits in well-being. We also review the overall safety profile and discuss the potential for dependence with CBMPs. Evidence can be drawn from a wide range of randomized and other controlled studies and from observational real-world studies. Most data from observational registry studies are supportive of ∆9-THC-based products (∆9-THC-predominant or balanced CBMPs) in the management of chronic neuropathic pain. Balanced products are also effective in reducing spasticity in multiple sclerosis. Most CBMPs show benefit in providing symptomatic benefits in reducing anxiety, nausea, and in improving sleep, but the place of specific products is more subtle, and choice guided by specific circumstances. Symptomatic improvements are accompanied by improved quality of life and well-being. Safety data indicate that CBMPs are generally well tolerated in most patients without specific contraindications. The majority of adverse effects are non-serious, and transient; most are principally associated with ∆9-THC and are dose-dependent. In contrast to recreational cannabis use, there is little evidence from clinical studies that CBMPs have any potential for dependence.

Medical cannabis for refractory cancer-related pain in a specialised clinical service: a cross-sectional study

BACKGROUND AND OBJECTIVES

Cancer-related pain management in advanced stages presents a significant challenge that often requires a multidisciplinary approach. Although advancements in pharmacological and interventional therapies, a considerable number of patients still suffer from refractory pain, leading to unmet clinical needs. This study shares our experience with medical cannabis (MC) as a potential therapy for this specific population of patients with cancer-related refractory pain.

METHODS

In a cross-sectional study, 252 consecutive refractory cancer-related pain patients (mean age=61.71, SD=14.02, 47.6% males) filled out detailed self-report questionnaires. Of these, 126 patients (55%) were treated with MC and 105 patients (45%) were not.

RESULTS

Most patients received pain management from their oncologist, not a pain specialist. MC was mainly started for pain relief, sleep difficulties and anorexia. About 70% of patients reported subjective improvement from MC, with almost 40% reporting a significant improvement in coping with their illness. Side effects were generally mild, with fatigue and dizziness being the most common (21.78% and 23.46%, respectively). No patient required dedicated medical care for side effects. Of non-users, 65% had tried MC before and stopped due to lack of effectiveness or side effects (39.7% and 34.6%, respectively).

CONCLUSION

Refractory cancer pain necessitates innovative approaches. This registry highlights that MC can effectively improve symptoms in non-responsive patients, with favourable safety profiles for this vulnerable population.

The State of Synthetic Cannabinoid Medications for the Treatment of Pain

Synthetic cannabinoids are compounds made in the laboratory to structurally and functionally mimic phytocannabinoids from the Cannabis sativa L. plant, including delta-9-tetrahydrocannabinol (THC). Synthetic cannabinoids (SCs) can signal via the classical endogenous cannabinoid system (ECS) and the greater endocannabidiome network, highlighting their signalling complexity and far-reaching effects. Dronabinol and nabilone, which mimic THC signalling, have been approved by the Food and Drug Administration (FDA) for treating nausea associated with cancer chemotherapy and/or acquired immunodeficiency syndrome (AIDS). However, there is ongoing interest in these two drugs as potential analgesics for a variety of other clinical conditions, including neuropathic pain, spasticity-related pain, and nociplastic pain syndromes including fibromyalgia, osteoarthritis, and postoperative pain, among others. In this review, we highlight the signalling mechanisms of FDA-approved synthetic cannabinoids, discuss key clinical trials that investigate their analgesic potential, and illustrate challenges faced when bringing synthetic cannabinoids to the clinic.

[Benefits and harms of cannabis-based medicines from the viewpoint of patients with chronic pain and their physicians : A cohort study in three pain centers of the German federal state Saarland]

BACKGROUND

There are no studies available that have simultaneously assessed the benefits and harms of cannabis-based medicines from the viewpoint of patients and their physicians.

METHODS

All chronic pain patients at three pain centres in the German federal state of Saarland who had received at least one prescription of cannabis-based medicines (CbMs) in the past from the study centre were included in a cross-sectional study from January 1 to December 31, 2021. Patients and their physicians completed a self-developed questionnaire separately.

RESULTS

All 187 contacted patients participated in the study. Since the start of CbM therapy, 44.9% of patients reported to be much or very much, 43.3% to be moderately and 8.0% to be slightly improved overall. A total of 2.7% reported no change and 1.1% a moderate deterioration of overall wellbeing. From the patients' point of view, the symptoms most frequently reported to have substantially improved were sleep problems (36.4%), muscle tension (25.1%) and appetite problems (22.1%). The most frequent bothersome side effects were sweating (6.4%), concentration problems (4.2%) and nausea (4.1%). Physicians noted substantial pain relief in 60.7%, improvement of sleep in 65.7% and of mental well-being in 34.3%. A complete cessation of opioids was achieved in 64.7%, of anticonvulsants in 57.9% and of antidepressants in 60% of patients that had received these medications before the start of CbM therapy.

CONCLUSIONS

CbMs can contribute to a clinically relevant reduction in pain, sleep problems and muscle tension and can improve daily functioning in carefully selected and supervised patients with chronic pain. CbM can contribute to the reduction or complete cessation of other pain medications (antidepressants, anticonvulsants, opioids).

[Patient-reported outcomes in chronic diseases under treatment with cannabis medicines : Analysis of the results of the Copeia survey]

BACKGROUND

The survey of Copeia captured early 2022 patient-reported outcomes (PRO) in Germany under cannabis medicinal product (CAM) therapy, with particular attention to symptoms, symptom changes, indications, side effects, dosages, and cost bearers.

GOAL

This study investigated the question of whether associations emerge from the results that could play a role in the indication and treatment monitoring of CAM in chronically ill patients.

MATERIALS AND METHODS

A standardized questionnaire was administered online nationwide in dialogue form over a 15-week period to collect itemized symptoms and PRO. Recruitment was supported by pharmacies, prescribing physicians, and patient associations. Inclusion criteria included physician-prescribed CAM therapy.

RESULTS AND DISCUSSION

Of 1582 participants, 1030 data sets (65%) could be completely analyzed. There was a heterogeneous patient population, whose common feature was disease chronicity. The frequency distribution of symptoms showed a homogeneous pattern for the respective indications, in which the most frequent six (pain 71%, sleep disturbance 64%, stress/tension 52%, inner restlessness 52%, depressive mood 44% and muscle tension 43%) seem to have a special significance. According to subjective assessment, quality of life improved significantly in 84% of all participating patients.

CONCLUSION

A symptom matrix (SMX) composed of different symptoms seems to play a special role in CAM therapy to improve the quality of life of chronically ill patients, regardless of the underlying disease. The SMX could contribute to the identification of an indication and to targeted treatment monitoring.

Knowledge, Attitudes, and Beliefs Regarding Medical Cannabis Among Patients and Providers in Florida's Long-Term Care Facilities

OBJECTIVES

Medical cannabis (MC) has been found effective in treating multiple symptoms commonly experienced by older adults; however, residents in long-term care (LTC) often lack access to MC products. This study seeks to identify patterns and barriers to recommending MC to patients and to explore the knowledge and attitudes toward MC use among patients and providers.

METHODS

The quantitative portion of this study employed a survey to assess the knowledge of, attitudes toward, and barriers to MC among 126 providers in Florida LTC. Frequencies were reported, bivariate associations were analyzed, and a final regression model predicting MC knowledge was tested. In-depth interviews were conducted with 25 LTC patients, and content was analyzed using the RADaR method.

RESULTS

The age of the providers ranged from 21 to 74; 74% were female, 18% were Black/African American, and 17% reported Hispanic ethnicity. Less than half (37.2%) felt they received adequate training on MC. Having accurate knowledge about MC was associated with greater confidence in answering patients' questions (p=0.002). Although most providers (94.2%) felt MC is a viable treatment option, the main barriers to recommending it to patients were a lack of proper training or clinical guidelines. Regarding patients, 16% reported ever using MC, and less than half (32%) had knowledge of MC or how to obtain products. Many believed it could help with symptoms and would consider its use if recommended by a doctor. However, they reported that MC was rarely recommended by providers and that they knew little about the use of this therapy.

CONCLUSION

This study underscores access challenges among seniors in LTC who might benefit most from MC's therapeutic properties. Complex MC policy implementation issues are discussed. State and federal policy issues around cannabis contribute to limited research on the therapeutic uses of cannabis, as well as the MC access problem addressed in this study.

Cannabinoid products for pain management: recommendations from the São Paulo State Society of Anesthesiology

There is growing interest in using cannabinoids across various clinical scenarios, including pain medicine, leading to the disregard of regulatory protocols in some countries. Legislation has been implemented in Brazil, specifically in the state of São Paulo, permitting the distribution of cannabinoid products by health authorities for clinical purposes, free of charge for patients, upon professional prescription. Thus, it is imperative to assess the existing evidence regarding the efficacy and safety of these products in pain management. In light of this, the São Paulo State Society of Anesthesiology (SAESP) established a task force to conduct a narrative review on the topic using the Delphi method, requiring a minimum agreement of 60% among panelists. The study concluded that cannabinoid products could potentially serve as adjuncts in pain management but stressed the importance of judicious prescription. Nevertheless, this review advises against their use for acute pain and cancer-related pain. In other clinical scenarios, established treatments should take precedence, particularly when clinical protocols are available, such as in neuropathic pain. Only patients exhibiting poor therapeutic responses to established protocols or demonstrating intolerance to recommended management may be considered as potential candidates for cannabinoids, which should be prescribed by physicians experienced in handling these substances. Special attention should be given to individual patient characteristics and the likelihood of drug interactions.

Unraveling the Tapestry of Pain: A Comprehensive Review of Ethnic Variations, Cultural Influences, and Physiological Mechanisms in Pain Management and Perception

The medical management of pain is a nuanced challenge influenced by sociocultural, demographic, and ethical factors. This review explores the intricate interplay of these dimensions in shaping pain perception and treatment outcomes. Sociocultural elements, encompassing cultural beliefs, language, societal norms, and healing practices, significantly impact individuals' pain experiences across societies. Gender expectations further shape these experiences, influencing reporting and responses. Patient implications highlight age-related and socioeconomic disparities in pain experiences, particularly among the elderly, with challenges in managing chronic pain and socioeconomic factors affecting access to care. Healthcare provider attitudes and biases contribute to disparities in pain management across racial and ethnic groups. Ethical considerations, especially in opioid use, raise concerns about subjective judgments and potential misuse. The evolving landscape of placebo trials adds complexity, emphasizing the importance of understanding psychological and cultural factors. In conclusion, evidence-based guidelines, multidisciplinary approaches, and tailored interventions are crucial for effective pain management. By acknowledging diverse influences on pain experiences, clinicians can provide personalized care, dismantle systemic barriers, and contribute to closing knowledge gaps, impacting individual and public health, well-being, and overall quality of life.

The Therapeutic Potential and Molecular Mechanisms Underlying the Neuroprotective Effects of Sativex® - A Cannabis-derived Spray

Sativex is a cannabis-based medicine that comes in the form of an oromucosal spray. It contains equal amounts of Δ9-tetrahydrocannabinol and cannabidiol, two compounds derived from cannabis plants. Sativex has been shown to have positive effects on symptoms of amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), and sleep disorders. It also has analgesic, antiinflammatory, antitumoral, and neuroprotective properties, which make it a potential treatment option for other neurological disorders. The article reviews the results of recent preclinical and clinical studies that support the therapeutic potential of Sativex and the molecular mechanisms behind its neuroprotective benefits in various neurological disorders. The article also discusses the possible advantages and disadvantages of using Sativex as a neurotherapeutic agent, such as its safety, efficacy, availability, and legal status.

The holistic effects of medical cannabis compared to opioids on pain experience in Finnish patients with chronic pain

BACKGROUND

Medical cannabis (MC) is increasingly used for chronic pain, but it is unclear how it aids in pain management. Previous literature suggests that MC could holistically alter the pain experience instead of only targeting pain intensity. However, this hypothesis has not been previously systematically tested.

METHOD

A retrospective internet survey was used in a sample of Finnish chronic pain patients (40 MC users and 161 opioid users). The patients evaluated statements describing positive and negative phenomenological effects of the medicine. The two groups were propensity score matched to control for possible confounding factors.

RESULTS

Exploratory factor analysis revealed three experience factors: Negative Side Effects, Positive Holistic Effects, and Positive Emotional Effects. The MC group (matched n = 39) received higher scores than the opioid group (matched n = 39) in Positive Emotional Effects with large effect size (Rank-Biserial Correlation RBC = .71, p < .001), and in Holistic Positive Effects with medium effect size (RBC = .47, p < .001), with no difference in Negative Side Effects (p = .13). MC and opioids were perceived as equally efficacious in reducing pain intensity. Ratings of individual statements were exploratively examined in a post hoc analysis.

CONCLUSION

MC and opioids were perceived to be equally efficacious in reducing pain intensity, but MC additionally positively affected broader pain-related factors such as emotion, functionality, and overall sense of wellbeing. This supports the hypothesis that MC alleviates pain through holistically altering the pain experience.

Looking Back, Moving Forward in Pain Medicine

Pain is an ancient medical complaint and a clinical riddle that has never been entirely solved. Looking back into history was the springboard to a look into the future of pain medicine. This article was based on a series of presentations given in a recent congress (May 2023) and represents the research, views, and opinions of the authors. Opium has been used for millennia to treat pain, but when it gained broad use in the United States in the 1980s and 1990s, it was so vastly overprescribed and mis-prescribed that it led to a public health crisis. This, in turn, led to the reaction where opioids at times were under-prescribed, leaving out many patients who may have benefited from opioids while leaving many legacy pain patients to manage withdrawal on their own and with few analgesic options. Cannabinoids (CB) were likewise widely used for various conditions, including pain, but were outlawed in the 20th century, only to be brought back as a potential analgesic agent. Interventional pain medicine is a developing discipline and has reinforced the concept of the interdisciplinary pain clinic. It plays an increasingly important part in modern medicine overall, especially with the support of ultrasound, for both diagnosis and therapy. Today, the views about pain have changed. Anyone has accepted that pain is not purely a physical phenomenon but a biopsychosocial phenomenon that occurs within a cultural context. Pain management remains a small but vitally important medical subspecialty that is critical from a functional enablement and population health perspective, which is helping to navigate new therapeutic targets, new drugs and routes of administration, greater understanding of pain psychology, and new technologies. Pain control today means early intervention, functional enablement through pain alleviation, educating patients about pain management, and minimizing the transition from acute to chronic pain.

Analgesic Effect of Buprenorphine for Chronic Noncancer Pain: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Buprenorphine is a partial agonist at the µ-opioid receptor and an antagonist at the delta and kappa opioid receptors. It has high affinity and low intrinsic activity at the µ-opioid receptor. Buprenorphine demonstrates no ceiling effect for clinical analgesia, but demonstrates this for respiratory depression and euphoria. It may provide effective analgesia while producing less adverse effects, making it a promising opioid analgesic. A systematic review and meta-analysis were performed to examine the analgesic efficacy of buprenorphine for patients with chronic noncancer pain.

METHODS

PubMed, MEDLNE, Embase, and the Cochrane Library were searched up to January 2022. Randomized controlled trials were included if they compared buprenorphine versus placebo or active analgesic in patients with chronic noncancer pain, where pain score was an outcome. Nonrandomized controlled trials, observational studies, qualitative studies, case reports, and commentaries were excluded. Two investigators independently performed the literature search, study selection, and data collection. A random-effects model was used. The primary outcome was the effect of buprenorphine on pain intensity in patients with chronic noncancer pain based on standardized mean difference (SMD) in pain score. Quality of evidence was assessed using the Grade of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

Two separate literature searches were conducted for patients with and without opioid use disorder (OUD). Only one study met the search criteria for those with OUD. Fourteen randomized controlled trials were included for those without OUD. Buprenorphine was associated with reduced pain score (SMD = -0.368, P < .001, I 2 = 89.37%) compared to placebo or active analgesic. Subgroup meta-analyses showed statistically significant differences in favor of buprenorphine versus placebo (SMD = -0.404, P < .001), for chronic low back pain (SMD = -0.383, P < .001), when administered via the transdermal route (SMD = -0.572, P = .001), via the buccal route (SMD = -0.453, P < .001), with length of follow-up lasting <12 weeks (SMD = -0.848, P < .05), and length of follow-up lasting 12 weeks or more (SMD = -0.415, P < .001). There was no significant difference when compared to active analgesic (SMD = 0.045, P > .05). Quality of evidence was low to moderate.

CONCLUSIONS

Buprenorphine was associated with a statistically significant and small reduction in pain intensity compared to placebo. Both the transdermal and buccal routes provided pain relief. There was more evidence supporting its use for chronic low back pain.

Cannabis: a multifaceted plant with endless potentials

Cannabis sativa, also known as "hemp" or "weed," is a versatile plant with various uses in medicine, agriculture, food, and cosmetics. This review attempts to evaluate the available literature on the ecology, chemical composition, phytochemistry, pharmacology, traditional uses, industrial uses, and toxicology of Cannabis sativa. So far, 566 chemical compounds have been isolated from Cannabis, including 125 cannabinoids and 198 non-cannabinoids. The psychoactive and physiologically active part of the plant is a cannabinoid, mostly found in the flowers, but also present in smaller amounts in the leaves, stems, and seeds. Of all phytochemicals, terpenes form the largest composition in the plant. Pharmacological evidence reveals that the plants contain cannabinoids which exhibit potential as antioxidants, antibacterial agents, anticancer agents, and anti-inflammatory agents. Furthermore, the compounds in the plants have reported applications in the food and cosmetic industries. Significantly, Cannabis cultivation has a minimal negative impact on the environment in terms of cultivation. Most of the studies focused on the chemical make-up, phytochemistry, and pharmacological effects, but not much is known about the toxic effects. Overall, the Cannabis plant has enormous potential for biological and industrial uses, as well as traditional and other medicinal uses. However, further research is necessary to fully understand and explore the uses and beneficial properties of Cannabis sativa.

Cannabis-based medicines and medical cannabis for adults with cancer pain

BACKGROUND

Pain is a common symptom in people with cancer; 30% to 50% of people with cancer will experience moderate-to-severe pain. This can have a major negative impact on their quality of life. Opioid (morphine-like) medications are commonly used to treat moderate or severe cancer pain, and are recommended for this purpose in the World Health Organization (WHO) pain treatment ladder. Pain is not sufficiently relieved by opioid medications in 10% to 15% of people with cancer. In people with insufficient relief of cancer pain, new analgesics are needed to effectively and safely supplement or replace opioids.

OBJECTIVES

To evaluate the benefits and harms of cannabis-based medicines, including medical cannabis, for treating pain and other symptoms in adults with cancer compared to placebo or any other established analgesic for cancer pain.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 26 January 2023.

SELECTION CRITERIA

We selected double-blind randomised, controlled trials (RCT) of medical cannabis, plant-derived and synthetic cannabis-based medicines against placebo or any other active treatment for cancer pain in adults, with any treatment duration and at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. The primary outcomes were 1. proportions of participants reporting no worse than mild pain; 2. Patient Global Impression of Change (PGIC) of much improved or very much improved and 3. withdrawals due to adverse events. Secondary outcomes were 4. number of participants who reported pain relief of 30% or greater and overall opioid use reduced or stable; 5. number of participants who reported pain relief of 30% or greater, or 50% or greater; 6. pain intensity; 7. sleep problems; 8. depression and anxiety; 9. daily maintenance and breakthrough opioid dosage; 10. dropouts due to lack of efficacy; 11. all central nervous system adverse events. We used GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We identified 14 studies involving 1823 participants. No study assessed the proportions of participants reporting no worse than mild pain on treatment by 14 days after start of treatment. We found five RCTs assessing oromucosal nabiximols (tetrahydrocannabinol (THC) and cannabidiol (CBD)) or THC alone involving 1539 participants with moderate or severe pain despite opioid therapy. The double-blind periods of the RCTs ranged between two and five weeks. Four studies with a parallel design and 1333 participants were available for meta-analysis. There was moderate-certainty evidence that there was no clinically relevant benefit for proportions of PGIC much or very much improved (risk difference (RD) 0.06, 95% confidence interval (CI) 0.01 to 0.12; number needed to treat for an additional beneficial outcome (NNTB) 16, 95% CI 8 to 100). There was moderate-certainty evidence for no clinically relevant difference in the proportion of withdrawals due to adverse events (RD 0.04, 95% CI 0 to 0.08; number needed to treat for an additional harmful outcome (NNTH) 25, 95% CI 16 to endless). There was moderate-certainty evidence for no difference between nabiximols or THC and placebo in the frequency of serious adverse events (RD 0.02, 95% CI -0.03 to 0.07). There was moderate-certainty evidence that nabiximols and THC used as add-on treatment for opioid-refractory cancer pain did not differ from placebo in reducing mean pain intensity (standardised mean difference (SMD) -0.19, 95% CI -0.40 to 0.02). There was low-certainty evidence that a synthetic THC analogue (nabilone) delivered over eight weeks was not superior to placebo in reducing pain associated with chemotherapy or radiochemotherapy in people with head and neck cancer and non-small cell lung cancer (2 studies, 89 participants, qualitative analysis). Analyses of tolerability and safety were not possible for these studies. There was low-certainty evidence that synthetic THC analogues were superior to placebo (SMD -0.98, 95% CI -1.36 to -0.60), but not superior to low-dose codeine (SMD 0.03, 95% CI -0.25 to 0.32; 5 single-dose trials; 126 participants) in reducing moderate-to-severe cancer pain after cessation of previous analgesic treatment for three to four and a half hours (2 single-dose trials; 66 participants). Analyses of tolerability and safety were not possible for these studies. There was low-certainty evidence that CBD oil did not add value to specialist palliative care alone in the reduction of pain intensity in people with advanced cancer. There was no difference in the number of dropouts due to adverse events and serious adverse events (1 study, 144 participants, qualitative analysis). We found no studies using herbal cannabis.

AUTHORS' CONCLUSIONS

There is moderate-certainty evidence that oromucosal nabiximols and THC are ineffective in relieving moderate-to-severe opioid-refractory cancer pain. There is low-certainty evidence that nabilone is ineffective in reducing pain associated with (radio-) chemotherapy in people with head and neck cancer and non-small cell lung cancer. There is low-certainty evidence that a single dose of synthetic THC analogues is not superior to a single low-dose morphine equivalent in reducing moderate-to-severe cancer pain. There is low-certainty evidence that CBD does not add value to specialist palliative care alone in the reduction of pain in people with advanced cancer.

Medicinal Cannabis Guidance and Resources for Health Professionals to Inform Clinical Decision Making

PURPOSE

Interest in the use of cannabis as a medicine has markedly increased during the last decade, with an unprecedented number of patients now seeking advice or prescriptions for medicinal cannabis. Unlike other medicines prescribed by physicians, many medicinal cannabis products have not undergone standard clinical trial development required by regulatory authorities. Different formulations with varying strengths and ratios of tetrahydrocannabinol and cannabidiol are available, and this diversity of medicinal cannabis products available for a myriad of therapeutic indications adds to the complexity. Physicians face challenges and barriers in their clinical decision making with medicinal cannabis because of current evidence limitations. Research efforts to address evidence limitations are ongoing; in the interim, educational resources and clinical guidance are being developed to address the gap in clinical information and support the needs of health professionals.

METHODS

This article provides an overview of various resources that health professionals may use when seeking information about medicinal cannabis in the absence of high-quality evidence and clinical guidelines. It also identifies examples of international evidence-based resources that support clinical decision making with medicinal cannabis.

FINDINGS

Similarities and differences between international examples of guidance and guideline documents are identified and summarized.

IMPLICATIONS

Guidance can help guide physicians in the individualized choice and dose of medicinal cannabis. Before quality clinical trials and regulator-approved products with risk management programs, safety data require clinical and academic collaborative pharmacovigilance.

Cannabis use disorder in patients with chronic pain: overestimation and underestimation in a cross-sectional observational study in 3 German pain management centres

ABSTRACT

There are concerns that cannabis use disorder (CUD) may develop in patients with chronic pain prescribed medical cannabis (MC). The criteria for CUD according to the Statistical Manual for Mental Disorders Version 5 (DSM-5) were not developed for the identification of patients using cannabis for therapeutic reasons. In addition, some items of CUD might be attributed to the desire of the patient to relieve the pain. Therefore, alternative strategies are needed to identify the true prevalence of CUD in persons with chronic pain being treated with MC. The prevalence of CUD in patients with chronic pain according to the DSM-5 criteria was assessed using an anonymous questionnaire in 187 consecutive patients attending 3 German pain centres in 2021. Questionnaires were rated as follows: (1) all criteria included, (2) removal of items addressing tolerance and withdrawal, and (3) removal of positive items if associated with the desire to relieve pain. Abuse was assessed by self-report (use of illegal drugs and diversion and illegal acquisition of MC) and urine tests for illegal drugs. Physicians recorded any observation of abuse. Cannabis use disorder according to the DSM-5 criteria was present in 29.9%, in 13.9% when items of tolerance and withdrawal were removed, and in 2.1% when positive behaviour items were removed. In 10.7%, at least 1 signal of abuse was noted. Urine tests were positive for nonprescribed drugs (amphetamines and tranquilizer) in 4.8% of subjects. Physicians identified abuse in 1 patient. In this study, the DSM-5 criteria overestimated and physicians underestimated the prevalence of CUD in patients prescribed MC for chronic pain.

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

INTRODUCTION

Pain is a global phenomenon encompassing many subtypes that include neuropathic, musculoskeletal, acute postoperative, cancer, and geriatric pain. Traditionally, opioids have been a mainstay pharmacological agent for managing many types of pain. However, opioids have been a subject of controversy with increased addiction, fatality rates, and cost burden on the US healthcare system. Cannabinoids have emerged as a potentially favorable alternative or adjunctive treatment for various types of acute and chronic pain. This narrative review seeks to describe the efficacy, risks, and benefits of cannabinoids as an adjunct or even potential replacement for opioids in the treatment of various subtypes of pain.

METHODS

In June of 2022, we performed a comprehensive search across multiple databases for English-language studies related to the use of cannabinoids in the treatment of various types pain: neuropathic pain, musculoskeletal pain, acute postoperative pain, cancer pain, and geriatric pain. Data from meta-analyses, systematic reviews, and randomized control trials (RCTs) were prioritized for reporting. We sought to focus our reported analysis on more recent literature as well as include older relevant studies with particularly notable findings.

RESULTS

There is conflicting evidence for the use of cannabinoids in the management of pain. While cannabinoids have shown efficacy in treating specific chronic pain subtypes such as neuropathic pain, fibromyalgia pain, and geriatric pain, they do not show as clear benefit in acute postoperative and the majority of musculoskeletal pain syndromes. Data trends towards cannabinoids having a positive effect in treating cancer pain, but results are not as conclusive. To date, there is a paucity of data comparing cannabinoids directly to opioids for pain relief. Overall, the side effects of cannabinoids appear to be relatively mild. However, there is still potential for addiction, altered brain development, psychiatric comorbidities, and drug-drug interactions.

CONCLUSION

Cannabinoids may be effective in specific subtypes of pain, but current evidence and guidelines do not yet support its use as the first-line treatment for any type of acute or chronic pain. Rather, it may be considered a good adjunct or alternative for patients who have failed more typical or conservative measures. Additional studies are needed with standardized forms of cannabinoids, route of delivery, and dosing for greater-powered analysis. Providers must weigh the individualized patient risks, benefits, and concurrent medication list in order to determine whether cannabinoids are appropriate for a patient's pain treatment plan.

Cannabis use, risk behaviours and harms in Brazil: A comprehensive review of available data indicators

ISSUES

Cannabis use and related health/social outcome indicator data for Brazil-where non-medical cannabis is generally illegal-are limited.

APPROACH

Towards a comprehensive overview of relevant indicators, we searched primary databases by combining MeSH-index terms related to cannabis, geographic location and subtopic terms (e.g., use, health, mortality) focusing on cannabis use and key outcome indicators in Brazil since 2010. In addition, relevant 'grey literature' (e.g., survey reports) was identified. Key indicator data were mainly narratively summarised.

KEY FINDINGS

Overall, cannabis use has increased somewhat since pre-2010, with (past-year) use rates measured at 2-3% for general population adults, yet 5% or higher among youth and/or (e.g., post-secondary) student populations. For key risk behaviours, the presence of tetrahydrocannabinol-positivity among motor-vehicle drivers has been measured at <2%. While the prevalence of cannabis use disorder appears to have decreased, the relative proportion of treatment provided for cannabis-related problems increased. National- and local-based studies indicated an association of cannabis use with mental health harms, including depression and suicidality. Although some non-representative and/or local studies contain information, other monitoring data, including cannabis-related risks and harms (e.g., cannabis-related driving, mortality, hospitalisations), are limited in availability.

IMPLICATIONS AND CONCLUSION

The prevalence of cannabis use in Brazil is comparably low (e.g., relative to elsewhere in the Americas). Data on numerous key cannabis-related indicators is absent, or limited in scope for Brazil. Considering ongoing evolutions in cannabis control and its status as the most common illicit drug, more comprehensive surveillance of cannabis use and related outcomes is advised.

Safety and effectiveness of cannabinoids to Danish patients with treatment refractory chronic pain-A retrospective observational real-world study

BACKGROUND

Cannabinoids are considered a therapeutic option to patients suffering from treatment refractory chronic pain (TRCP) insufficiently relieved by conventional analgesics or experiencing intolerable adverse events (AEs) from those. This study aimed to explore safety and effectiveness of oral cannabinoids among patients with TRCP.

METHODS

A retrospective study was conducted among Danish patients with TRCP being prescribed oral cannabinoids. Data on AEs and changes in pain intensity by numeric rating scale (NRS) before and after initiation of oral cannabinoid therapy were analysed.

RESULTS

Among 826 eligible patients ≥18 years old, 529 (64%) were included for data analysis at first follow-up (F/U1) (median 56 days from baseline) and 214 (26%) for second follow-up (F/U2) (median 126 days from F/U1). Mean age was 60 ± 15.9 years and 70% were females. AEs were in general reported mild to moderate by 42% of patients at F/U1 and 34% at F/U2. AEs were mainly related to gastrointestinal (F/U1: 17% and F/U2: 13%) and nervous system disorders (F/U1: 14% and F/U2: 11%). Reduction in NRS was significantly different at both follow-up consultations compared with baseline (<0.0001). Clinically relevant pain reduction (NRS ≥30%) was reported by 17% at F/U1 and 10% of patients at F/U2 in intention-to-treat analysis whereas the figures were 32% and 45% respectively, in per-protocol analysis.

CONCLUSION

Oral cannabinoid therapy seems to be safe and mildly effective in patients with TRCP. Randomized controlled trials with focus on comparable pain characteristics in diagnostical homogenous patient subgroups are needed for further improvement of evidence level for relief of chronic pain using oral cannabinoids.

SIGNIFICANCE

The findings in this retrospective study conducted in a real-world clinical setting suggest a favourable safety profile of cannabinoids. Moreover, one-sixth (intention-to-treat) and one-third (per-protocol) of patients with chronic pain refractory to conventional analgesics, or experiencing intolerable adverse effects, benefited significantly from therapy with oral cannabinoid regimens. Combination of THC and CBD seems overall more effective than cannabinoid monotherapy. Conduction of randomized controlled trials investigating safety and efficacy of cannabinoid therapy to diagnosis specific patient subgroups with comparable clinical and pathophysiological chronic pain characteristics is warranted, hence contributing further to the process of clinical evidence clarification currently in progress.

Off-label pharmacological treatment for neuropathic pain: A Delphi study by the Spanish Pain Society Neuropathic Pain Task Force

OBJECTIVES

The use of off-label pharmacotherapies for neuropathic pain (NP) is growing relating to the many unmet needs of patients. However, clinical guidelines fail to address it, and the available evidence is sparse and fragmented. We arranged a formal expert consensus to address this controversial issue and provide some guidance on judicious use.

METHODS

A two-round standard Delphi survey that involved pain clinic specialists with experience in the research and management of NP was done over an ad hoc 40-item questionnaire prepared by the authors. Consensus on each statement was defined as at least either 80% endorsement or rejection after the second round.

RESULTS

Forty-three and thirty-seven panelists participated in the first and second round, respectively. Consensus was reached in 34 out of 40 statements. Endorsed alternatives for unresponsive patients include non-gabapentinoid antiepileptics (oxcarbazepine and eslicarbazepine), venlafaxine, intravenous lidocaine (when doses can be optimized), and some vaporized cannabinoids (under appropriate surveillance). In addition, lacosamide, low-dose naltrexone, propofol, or ketamine could prove beneficial if subjected to more research. Other options were rejected, and there was controversy about the usefulness of topical preparations.

DISCUSSION

For patients who do not respond to standard NP treatments, some other viable pharmacological options can be attempted before advancing to other therapeutic stages. This may help patients who are reluctant to or have some contraindication for interventional therapies.

Mental disorders are no predictors to determine the duration of cannabis-based treatment for chronic pain

Background

Chronic pain (CP), a complex biopsychosocial disorder with a global prevalence of up to 33%, can be treated by following multidisciplinary approaches that may include cannabis-based medicine (CBM). However, because CBM continues to be a new treatment, questions remain regarding the ideal duration for CBM and its psychosocial determinants, including mental comorbidities.

Methods

In a retrospective cross-sectional study involving 46 patients with CP (ICD-10 code F45.4-), three validated instruments-the German Pain Questionnaire, the Depression Anxiety Stress Scale (DASS), and the Marburg Questionnaire of Habitual WellBeing-were used to identify pain-specific psychosocial determinants and mental disorders. Descriptive analyses, a group differences analysis, and a logistic regression analysis were performed using SPSS.

Results

The patients most frequently reported low back pain as the primary location of their CP, and in attributing the condition to tissue damage, most had largely adopted a somatic orientation in conceptualizing their illness. Most had experienced CP for more than 5 years (M = 5.13 years, SD = 1.41) and, as a consequence, faced significant restrictions in their everyday life and exhibited low subjective wellbeing (MFHW median = 4.00, N = 43, Q1: 2.00, Q3: 9.00, range: 0-20). Comorbidities among the patients included depression, (DASS-Depression, median: 11.50, Q1: 7.00, Q3: 16.25), anxiety (DASS-Anxiety, median: 4.50, Q1: 2.75, Q3: 8.00), and stress (DASS-Stress, median: 11.00, Q1: 7.00, Q3: 15.00). Between the two cannabis-based treatments with a course lasting either less or more than a year, the duration of treatment showed no between-group differences in terms of sociodemographic factors, pain-specific factors, conceptualizations of the illness, or mental disorders. Psychosocial determinants such as subjective wellbeing and mental comorbidities were not significant predictors of the duration of cannabis-based treatment.

Conclusion

We found no evidence indicating that the benefits of short-term vs. long-term cannabis-based treatment can be predicted by mental comorbidities or psychosocial factors. However, because CBM may be included in approaches to treat CP, questions about the ideal duration of such treatment remain to be answered.

Cannabinoids as Prospective Anti-Cancer Drugs: Mechanism of Action in Healthy and Cancer Cells

Endogenous and exogenous cannabinoids modulate many physiological and pathological processes by binding classical cannabinoid receptors 1 (CB1) or 2 (CB2) or non-cannabinoid receptors. Cannabinoids are known to exert antiproliferative, apoptotic, anti-migratory and anti-invasive effect on cancer cells by inducing or inhibiting various signaling cascades. In this chapter, we specifically emphasize the latest research works about the alterations in endocannabinoid system (ECS) components in malignancies and cancer cell proliferation, migration, invasion, angiogenesis, autophagy, and death by cannabinoid administration, emphasizing their mechanism of action, and give a future perspective for clinical use.

[Diabetic neuropathy and diabetic foot syndrome (update 2023)]

These are the guidelines for diagnosis and treatment of diabetic neuropathy and diabetic foot.The position statement summarizes characteristic clinical symptoms and techniques for diagnostic assessment of diabetic neuropathy, including the complex situation of the diabetic foot syndrome. Recommendations for the therapeutic management of diabetic neuropathy, especially for the control of pain in sensorimotor neuropathy, are provided. The needs to prevent and treat diabetic foot syndrome are summarized.

[Cannabinoids reduce opioid use in older patients with pain : Retrospective three-year analysis of data from a general practice]

BACKGROUND

Relevant data for the prescription and therapeutic effects of medical cannabinoids (CAM) are still missing in everyday medicine especially for elderly and geriatric patients.

AIM OF THE STUDY

Documentation of prescription (duration, age) of CAM (dronabinol, nabiximols, cannabinoid extracts) and co-medicated opioids in a doctor's office specializing in pain.

METHODS

Analysis of the consumption of opioids (morphine equivalent) and CAM (THC equivalent) for age and gender.

RESULTS

In all, 178 patients with chronic pain were treated for a period of 366 days (median; range 31-2590 days). Median age was 72 years (26-96 years); 115 were women (64.8%). Of these, 34 were younger than 65 years, 42 were 65-80 years and 40 were more than 80 years old. Of the 63 men, 29 were younger than 65 years, 24 were 65-80 years and 10 were older than 80 years. Indications for CAM were chronic pain and the limitations for opioids because of side effects and worsening of quality of life. To total of 1001 CAM were prescribed, 557 (55.6%) dronabinol as liquid, 328 (32.7%) as full spectrum extracts and 66 (6.6%) as oro-mucosal nabiximols spray. 50 prescriptions (5%) contained more than one CAM simultaneously. The daily consumption of dronabinol liquor and extracts were 9.6 mg/day (median), and of spray 13.6 mg. The dosage over time did not change in patients older than 64; in younger patients, there was a non-significant increasing trend. Women requested lower THC dosages compared to men (8.1 mg vs. 14.8 mg). Furthermore, 10 patients (5.6%) stopped CAM because of failing effectivity, 7 (3.9%) because of failing cost coverage and only 5 because of adverse side effects. 115 patients (65%) with CAM also received opioids a median 65 mg/day morphine equivalents. This opioid dosage was significantly reduced in course of time by 24 mg/day morphine equivalents or 50%. This reduction was independent on CAM dosage, age and gender.

DISCUSSION

Patients with chronic pain profit from long-term CAM which safely and significantly lower the consumption of comedicated opioids, even at low dosages (< 7.5 mg/day). For women, low-dose THC may be sufficient. Older patients benefit from CAM, and adverse effects do not limit the (chronic) use and prescription of CAM in the elderly.

Cannabis in der Onkologie – viel Rauch um nichts?

Die medizinische Verwendung von Cannabis hat in den letzten Jahren in Europa und Nordamerika an Popularität gewonnen. Cannabinoide sind sowohl als Fertigarzneimittel als auch in Blüten- und Extraktform verfügbar. Der vorliegende Artikel legt den Fokus auf die supportive Therapie onkologischer Patienten. Mögliche Indikationen sind Schmerzen, Chemotherapie-bedingte Übelkeit und Erbrechen, Appetitlosigkeit und Geschmacksveränderungen. Trotz des enormen Hypes um Cannabis als Medizin ist die Evidenz für dessen Anwendung bei onkologischen Patienten unzureichend. Palliativpatienten mit refraktären Symptomen könnten jedoch geeignete Kandidaten für einen Therapieversuch darstellen. Der entscheidende Parameter für die Auswahl eines Cannabis-Arzneimittels ist die THC/CBD-Ratio. Orale Einnahmeformen bieten sich gerade für Cannabis-naive und ältere Patienten an. Psychische und kardiovaskuläre Nebenwirkungen sind nicht zu unterschätzen.

Application of experimental design in HPLC method optimisation for the simultaneous determination of multiple bioactive cannabinoids

The scientific interest in Cannabis sativa L. analysis has been rapidly increasing in recent years, especially for what concerns cannabinoids, plant secondary metabolites which are well known for having many biological properties. High-performance liquid chromatography (HPLC) is frequently used for both the qualitative and quantitative analysis of cannabinoids in plant extracts from C. sativa and its derived products. Many studies have been focused on the main cannabinoids, such as ∆⁹-tetrahydrocannabinolic acid (∆⁹-THCA), cannabidiolic acid (CBDA), cannabigerolic acid (CBGA) and their decarboxylated derivatives, such as ∆⁹-tetrahydrocannabinol (∆⁹-THC), cannabidiol (CBD) and cannabigerol (CBG). In addition to the abovementioned compounds, the plant produces other metabolites of the same chemical class, and some of them have shown interesting biological activities. In the light of this, it is important to have efficient analytical methods for the simultaneous separation of cannabinoids, which is quite complex since they present similar chemical-physical characteristics. The present work is focused on the use of the Design of Experiments technique (DoE) to develop and optimise an HPLC method for the simultaneous separation of 14 cannabinoids. Experimental design optimisation was applied by using a Central Composite Face-Centered design to achieve the best resolution with minimum experimental trials. Five significant variables affecting the chromatographic separation, including ammonium formate concentration, gradient elution, run time and flow rate, were studied. A multivariate strategy, based on Principal Component Analysis (PCA) and Partial Least Squared (PLS) regression, was used to define the best operative conditions. The developed method allowed for the separation of 12 out of 14 cannabinoids. Due to co-elution phenomena, HPLC coupled with a triple quadrupole mass analyser (HPLC-ESI-MS/MS) was applied, monitoring the specific transitions of each compound in the multiple reaction monitoring (MRM) mode. Finally, the optimised method was applied to C. sativa extracts having a different cannabinoid profile to demonstrate its efficiency to real samples. The methodology applied in this study can be useful for the separation of other cannabinoid mixtures, by means of appropriate optimisation of the experimental conditions.

Antiviral activity of medicinal plant-derived products against SARS-CoV-2

This review presents information from several studies that have demonstrated the antiviral activity of extracts (Andrographis paniculata, Artemisia annua, Artemisia afra, Cannabis sativa, Curcuma longa, Echinacea purpurea, Olea europaea, Piper nigrum, and Punica granatum) and phytocompounds derived from medicinal plants (artemisinins, glycyrrhizin, and phenolic compounds) against SARS-CoV-2. A brief background of the plant products studied, the methodology used to evaluate the antiviral activity, the main findings from the research, and the possible mechanisms of action are presented. These plant products have been shown to impede the adsorption of SARS-CoV-2 to the host cell, and prevent multiplication of the virus post its entry into the host cell. In addition to antiviral activity, the plant products have also been demonstrated to exert an immunomodulatory effect by controlling the excessive release of cytokines, which is commonly associated with SARS-CoV-2 infections.

Predictors of Pain Reduction Among Fibromyalgia Patients Using Medical Cannabis: A Long-Term Prospective Cohort Study

OBJECTIVE

Many patients with fibromyalgia (FM) report using cannabis as a strategy to improve pain. Given that pain often co-occurs with symptoms of anxiety and depression (i.e., negative affect) and sleep problems among patients with FM, improvements in these symptoms might indirectly contribute to reductions in pain intensity following cannabis use. The main objective of the study was to examine whether changes in pain intensity following initiation of medical cannabis among patients with FM could be attributed to concurrent changes (i.e., reductions) in negative affect and sleep problems.

METHODS

This was a 12-month prospective cohort study among patients with FM (n = 323) initiating medical cannabis under the care of physicians. Patients were assessed at baseline, and follow-up assessment visits occurred every 3 months after initiation of medical cannabis. Patients' levels of pain intensity, negative affect, and sleep problems were assessed across all visits.

RESULTS

Multilevel mediation analyses indicated that reductions in patients' levels of pain intensity were partly explained by concurrent reductions in sleep problems and negative affect (both P < 0.001). This remained significant even when accounting for patients' baseline characteristics or changes in medical cannabis directives over time (all P > 0.05).

CONCLUSION

Our findings provide preliminary insight into the potential mechanisms of action underlying pain reductions among patients with FM who are using medical cannabis. Given the high attrition rate (i.e., 75%) observed in the present study at 12 months, our findings cannot be generalized to all patients with FM who are using medical cannabis.

[Cannabis in oncology - much ado about nothing?]

The medical use of Cannabis has gained popularity in Europe and Northern America in recent years. Cannabinoids are available as finished pharmaceuticals, flowers and extracts. This article focuses on supportive medicine for oncological patients. Possible indications are pain, chemotherapy-induced nausea and vomiting, loss of appetite and altered taste perception. Despite the enormous cannabis hype in medicine, the evidence for its use in oncology patients is insufficient. However, palliative patients with refractory symptoms could be candidates for a therapeutic trial. The key parameter for choosing a cannabis medicinal product is the THC/CBD ratio. Oral forms of administration are particularly suitable for cannabis-naive and older patients. Mental and cardiovascular side effects should not be underestimated.

Characteristics of People Seeking Prescribed Cannabinoids for the Treatment of Chronic Pain: Evidence From Project Twenty 21

Background

Prescribed cannabinoids are now legal in the UK and increasingly being used for a variety of conditions, with one of the most frequent conditions being chronic pain. This paper describes the characteristics of individuals seeking prescribed cannabinoids for the treatment of chronic pain in Project Twenty 21, a UK based real world data registry of prescribed cannabis patients.

Method

By 1st November 2021 data were available for 1,782 people who had sought treatment with medical cannabis as part of Project Twenty 21. The most common diagnosis among this cohort was chronic pain with 949 (53.5%) of the cohort reporting a primary condition related to chronic pain. Medical and self-report data on the characteristics of these patients, their health status and type/s of cannabinoid/s prescribed are summarized in this report.

Results

Of the 949 people reporting chronic pain as a primary condition 54.7% were male and their average age was 42.0 years (range = 18-84). Patients reported a low quality of life and high levels of comorbidity: people reported an average of 4.6 comorbid conditions with the most common comorbid conditions including anxiety, depression, insomnia and stress. A range of cannabinoid products were prescribed with the most common products being classified as high THC flower (48.5%). The majority of patients also reported using at least one other prescribed medication (68.7%).

Conclusions

Consistent with findings in other national and international databases, chronic pain was the most common primary condition in this real world study of prescribed cannabinoids. There was considerable variation in the types of chronic pain, comorbid pathology and in the characteristics of products being prescribed to treat these conditions. Together, this evidence supports the utility of real world evidence, as opposed to clinical trial approaches to studying the potential benefits of prescribed cannabinoids in treating chronic pain.

Systematic reviews of randomized controlled trials of cannabinoid products in chronic pain conditions and for symptoms associated with multiple sclerosis: what do they tell us?

INTRODUCTION

: To investigate whether published systematic reviews of randomized controlled trials provide sufficient clarity to inform prescribing of cannabinoid products aimed for medicinal use, we examined their features and findings in two well-researched areas: chronic cancer/noncancer pain and multiple sclerosis (MS)-related symptoms.

AREAS COVERED

: Structured searches from January 2011 to 2 February 2021 identified 31 systematic reviews (with/without meta-analyses) that met the inclusion criteria. Support for the efficacy of cannabinoids was minimal in cancer pain, and somewhat stronger in noncancer (especially neuropathic) pain and MS spasticity. All systematic reviews and most meta-analyses grouped cannabinoid products together without appropriate consideration of their differential attributes (active constituent(s), concentration/strength, dosage forms, administration route), dosing regimens or treatment durations. Patient populations and efficacy outcome measures were inhomogeneous, particularly for studies in noncancer pain and MS. Separate results for specific cannabinoid formulations were rarely provided.

EXPERT OPINION

: The therapeutic effect of cannabinoids, as already demonstrated for some products, is not reflected clearly in the current range of systematic reviews and meta-analyses in chronic pain and MS. To truly inform evidence-based practice, future publications should aim to present results by individual product from well-conducted clinical trials using appropriate and homogeneous outcome measures in well-defined patient populations.

Neurogenic inflammation as a novel treatment target for chronic pain syndromes

Chronic pain syndrome is a heterogeneous group of diseases characterized by several pathological mechanisms. One in five adults in Europe may experience chronic pain. In addition to the individual burden, chronic pain has a significant societal impact because of work and school absences, loss of work, early retirement, and high social and healthcare costs. Several anti-inflammatory treatments are available for patients with inflammatory or autoimmune diseases to control their symptoms, including pain. However, patients with degenerative chronic pain conditions, some with 10-fold or more elevated incidence relative to these manageable diseases, have few long-term pharmacological treatment options, limited mainly to non-steroidal anti-inflammatory drugs or opioids. For this review, we performed multiple PubMed searches using keywords such as "pain," "neurogenic inflammation," "NGF," "substance P," "nociception," "BDNF," "inflammation," "CGRP," "osteoarthritis," and "migraine." Many treatments, most with limited scientific evidence of efficacy, are available for the management of chronic pain through a trial-and-error approach. Although basic science and pre-clinical pain research have elucidated many biomolecular mechanisms of pain and identified promising novel targets, little of this work has translated into better clinical management of these conditions. This state-of-the-art review summarizes concepts of chronic pain syndromes and describes potential novel treatment strategies.

Long-term observational studies with cannabis-based medicines for chronic non-cancer pain: A systematic review and meta-analysis of effectiveness and safety

BACKGROUND AND OBJECTIVE

This systematic review evaluated the effectiveness, tolerability and safety of cannabis-based medicines (CbMs) for chronic non-cancer pain (CNCP) in long-term observational studies.

DATABASES AND DATA TREATMENT

CENTRAL, EMBASE and MEDLINE were searched to December 2021. We included prospective observational studies with a study duration ≥ 26 weeks. Pooled estimates of event rates of categorical data and standardized mean differences (SMD) of continuous variables were calculated using a random effects model.

RESULTS

Six studies were included with 2686 participants, with study duration ranging between 26 and 52 weeks. Pain conditions included were nociceptive, nociplastic, neuropathic and mixed pain. The certainty of evidence for every outcome was very low. The weighted mean difference of mean pain reduction was 1.75 (95% Confidence interval [CI] 0.72 to 2.78) on a 0-10 scale. 20.8 % (95% CI 10.2 % to 34.0 %) of patients reported pain relief of 50% or greater. The effect size for sleep problems was moderate and for depression and anxiety was low. Study completions was reported for 53.3% (95% CI 26.8% to 79.9%) of patients, with dropouts of 6.8 % (95% CI 4.3% to 9.7%) due to adverse events. Serious adverse events occurred in 3.0% (95 CI 0.02 % to 12.8%) and 0.3 % (95% CI 0.1% to 0.6%) of patients died.

CONCLUSIONS

Information included in observational studies should be regarded with caution.Within the context of observational studies, CbMs had positive effects on multiple symptoms for some CNCP patients and were generally well tolerated and safe.

From a Symptom-Based to a Mechanism-Based Pharmacotherapeutic Treatment in Complex Regional Pain Syndrome

Complex regional pain syndrome (CRPS) is a debilitating painful condition of a distal extremity that can develop after tissue damage. CRPS is thought to be a multimechanism syndrome and ideally the most prominent mechanism(s) should be targeted by drugs in an individually tailored manner. This review gives an overview of the action and evidence of current and future pharmacotherapeutic options for CRPS. The available options are grouped in four categories by their therapeutic actions on the CRPS mechanisms, i.e. inflammation, central sensitisation, vasomotor disturbances and motor disturbances. More knowledge about the underlying mechanisms of CRPS helps to specifically target important CRPS mechanisms. In the future, objective biomarkers could potentially aid in selecting appropriate mechanism-based drugs in order to increase the effectiveness of CRPS treatment. Using this approach, current and future pharmacotherapeutic options for CRPS should be studied in multicentre trials to prove their efficacy. The ultimate goal is to shift the symptom-based selection of therapy into a mechanism-based selection of therapy in CRPS.

New approaches to treatments for sleep, pain and autonomic failure in Parkinson's disease - Pharmacological therapies

Non-motor symptoms (NMSs) are highly prevalent throughout the course of Parkinson's disease (PD). Pain, autonomic dysfunction and sleep disturbances remain at the forefront of the most common NMSs; their treatment is challenging and their effect on the quality of life of both patients and caregivers detrimental. Yet, the landscape of clinical trials in PD is still dominated by therapeutic strategies seeking to ameliorate motor symptoms; subsequently, effective strategies to successfully treat NMSs remain a huge unmet need. Wider awareness among industry and researchers is thus essential to give rise to development and delivery of high-quality, large-scale clinical trials in enriched populations of patients with PD-related pain, autonomic dysfunction and sleep. In this review, we discuss recent developments in the field of pharmacological treatment strategies designed or re-purposed to target three key NMSs: pain, autonomic dysfunction and sleep disturbances. We focus on emerging evidence from recent clinical trials and outline some exciting and intriguing findings that call for further investigations.

To Treat or Not to Treat? Polish Physicians' Opinions about the Clinical Aspects of Cannabinoids-An Online Survey

Introduction: Medical cannabis’ importance in Poland increased dramatically following its legalization as the 12th country in Europe in 2017. However, no studies have been published to give insight into Polish physicians’ opinions about medical cannabis. Objectives: To investigate physician’s opinions about cannabinoids’ utility in clinical practice, concerns regarding their safety profile, and their clinical experience with cannabinoids. Methods: The survey using a self-developed tool was conducted online; participants were physicians with or without specialist training. Participation was voluntary. Physicians were recruited through personal networks, palliative care courses, and Medical Chambers. Results: From June to October 2020, we recruited 173 physicians from 15/16 voivodeships. The largest age group (43.9%; n = 76) was 30–39 year-olds. A similar proportion declared they never used cannabis and did not receive any training regarding cannabinoids (60% for both). Only 15 (8%) ever prescribed medical cannabis, although about 50% declared knowing suitable patients for such therapy, and 53.8% had at least one patient proactively asking for such treatment in the last 6 mo. The most common indication chosen was pain: chronic cancer-related (n = 128), chronic non-cancer (n = 77), and neuropathic (n = 60). Other commonly chosen conditions were alleviation of cancer treatment side-effects (n = 56) and cachexia (n = 57). The overall safety profile of THC was assessed as similar to most commonly used medications, including opioids; NSAIDs and benzodiazepines were, however, perceived as safer. Conclusions: Polish physicians favored the legalization of medical cannabis. However, it is of concern that a limited number have any experience with prescribing cannabis. The creation of clear guidelines to advise physicians in their routine practice and education about pain management and the risks related to the consumption of recreational cannabis for medical conditions are needed.

Lower-Risk Cannabis Use Guidelines (LRCUG) for reducing health harms from non-medical cannabis use: A comprehensive evidence and recommendations update

BACKGROUND

Cannabis use is common, especially among young people, and is associated with risks for various health harms. Some jurisdictions have recently moved to legalization/regulation pursuing public health goals. Evidence-based 'Lower Risk Cannabis Use Guidelines' (LRCUG) and recommendations were previously developed to reduce modifiable risk factors of cannabis-related adverse health outcomes; related evidence has evolved substantially since. We aimed to review new scientific evidence and to develop comprehensively up-to-date LRCUG, including their recommendations, on this evidence basis.

METHODS

Targeted searches for literature (since 2016) on main risk factors for cannabis-related adverse health outcomes modifiable by the user-individual were conducted. Topical areas were informed by previous LRCUG content and expanded upon current evidence. Searches preferentially focused on systematic reviews, supplemented by key individual studies. The review results were evidence-graded, topically organized and narratively summarized; recommendations were developed through an iterative scientific expert consensus development process.

RESULTS

A substantial body of modifiable risk factors for cannabis use-related health harms were identified with varying evidence quality. Twelve substantive recommendation clusters and three precautionary statements were developed. In general, current evidence suggests that individuals can substantially reduce their risk for adverse health outcomes if they delay the onset of cannabis use until after adolescence, avoid the use of high-potency (THC) cannabis products and high-frequency/-intensity of use, and refrain from smoking-routes for administration. While young people are particularly vulnerable to cannabis-related harms, other sub-groups (e.g., pregnant women, drivers, older adults, those with co-morbidities) are advised to exercise particular caution with use-related risks. Legal/regulated cannabis products should be used where possible.

CONCLUSIONS

Cannabis use can result in adverse health outcomes, mostly among sub-groups with higher-risk use. Reducing the risk factors identified can help to reduce health harms from use. The LRCUG offer one targeted intervention component within a comprehensive public health approach for cannabis use. They require effective audience-tailoring and dissemination, regular updating as new evidence become available, and should be evaluated for their impact.

Cannabis-Based Medicines and Medical Cannabis for Chronic Neuropathic Pain

Neuropathic pain represents a broad category of pain syndromes that include a wide variety of peripheral and central disorders. The overall prevalence of neuropathic pain in the general population is reported to be between 7 and 10%. Management of neuropathic pain presents an unmet clinical need, with less than 50% of patients achieving substantial pain relief with medications currently recommended such as pregabalin, gabapentin, duloxetine and various tricyclic antidepressants. It has been suggested that cannabis-based medicines (CbMs) and medical cannabis (MC) may be a treatment option for those with chronic neuropathic pain. CbMs/MC are available in different forms: licensed medications or medical products (plant-derived and/or synthetic products such as tetrahydrocannabinol or cannabidiol); magistral preparations of cannabis plant derivatives with defined molecular content such as dronabinol (tetrahydrocannabinol); and herbal cannabis with a defined content of tetrahydrocannabinol and/or cannabidiol, together with other active ingredients (phytocannabinoids other than cannabidiol/tetrahydrocannabinol, terpenes and flavonoids). The availability of different types of CbMs/MC varies between countries worldwide. Systematic reviews of available randomised controlled trials have stated low-quality evidence for CbMs and MC for chronic neuropathic pain. Depending on the studies included in the various quantitative syntheses, authors have reached divergent conclusions on the efficacy of CbMs/MC for chronic neuropathic pain (from not effective to a clinically meaningful benefit). Clinically relevant side effects of CbMs/MC, especially for central nervous system and psychiatric disorders, have been reported by some systematic reviews. Recommendations for the use of CbMs/MC for chronic neuropathic pain by various medical associations also differ, from negative recommendations, no recommendation possible, recommended as third-line therapy, or recommended as an alternative in selected cases failing standard therapies within a multimodal concept. After reading this paper, readers are invited to formulate their own conclusions regarding the potential benefits and harms of CbMs/MC for the treatment of chronic neuropathic pain.

UK Medical Cannabis registry: an analysis of clinical outcomes of medicinal cannabis therapy for chronic pain conditions

OBJECTIVES

To explore pain-specific, general health-related quality of life (HRQoL), and safety outcomes of chronic pain patients prescribed cannabis-based medicinal products (CBMPs).

METHODS

A case series was performed using patients with chronic pain from the UK Medical Cannabis Registry. Primary outcomes were changes in Brief Pain Inventory short-form (BPI), Short-form McGill Pain Questionnaire-2 (SF-MPQ-2), Visual Analogue Scale-Pain (VAS), General Anxiety Disorder-7 (GAD-7), Sleep Quality Scale (SQS), and EQ-5D-5L, at 1, 3, and 6 months from baseline. Statistical significance was defined at p-value<0.050.

RESULTS

190 patients were included. Median initial Δ⁹-tetrahydrocannabinol and cannabidiol daily doses were 2.0mg (range:0.0-442.0mg) and 20.0mg (range:0.0-188.0mg) respectively. Significant improvements were observed within BPI, SF-MPQ-2, GAD-7, SQS, EQ-5D-5 L index, and VAS measures at all timepoints (p<0.050). Seventy-five adverse events (39.47%) were reported, of which 37 (19.47%) were rated as mild, 23 (12.11%) as moderate, and 14 (7.37%) as severe. Nausea (n=11; 5.8%) was the most frequent adverse event.

CONCLUSION

An association was identified between patients with chronic pain prescribed CBMPs and improvements in pain-specific and general HRQoL outcomes. Most adverse events were mild to moderate in severity, indicating CBMPs were well tolerated. Inherent limitations of study design limit its overall applicability.

Cannabis-Based Medicines and Medical Cannabis in the Treatment of Nociplastic Pain

Nociplastic pain is defined as pain due to sensitization of the nervous system, without a sufficient underlying anatomical abnormality to explain the severity of pain. Nociplastic pain may be manifest in various organ systems, is often perceived as being more widespread rather than localized and is commonly associated with central nervous system symptoms of fatigue, difficulties with cognition and sleep, and other somatic symptoms; all features that contribute to considerable suffering. Exemplified by fibromyalgia, nociplastic conditions also include chronic visceral pain, chronic headaches and facial pain, and chronic musculoskeletal pain. It has been theorized that dysfunction of the endocannabinoid system may contribute to persistent pain in these conditions. As traditional treatments for chronic pain in general and nociplastic pain in particular are imperfect, there is a need to identify other treatment options. Cannabis-based medicines and medical cannabis (MC) may hold promise and have been actively promoted by the media and advocacy. The medical community must be knowledgeable of the current evidence in this regard to be able to competently advise patients. This review will briefly explain the understanding of nociplastic pain, examine the evidence for the effect of cannabinoids in these conditions, and provide simplified guidance for healthcare providers who may consider prescribing cannabinoids for these conditions.

Medical cannabis or cannabinoids for chronic pain: a clinical practice guideline

CLINICAL QUESTION

What is the role of medical cannabis or cannabinoids for people living with chronic pain due to cancer or non-cancer causes?

CURRENT PRACTICE

Chronic pain is common and distressing and associated with considerable socioeconomic burden globally. Medical cannabis is increasingly used to manage chronic pain, particularly in jurisdictions that have enacted policies to reduce use of opioids; however, existing guideline recommendations are inconsistent, and cannabis remains illegal for therapeutic use in many countries.

RECOMMENDATION

The guideline expert panel issued a weak recommendation to offer a trial of non-inhaled medical cannabis or cannabinoids, in addition to standard care and management (if not sufficient), for people living with chronic cancer or non-cancer pain.

HOW THIS GUIDELINE WAS CREATED

An international guideline development panel including patients, clinicians with content expertise, and methodologists produced this recommendation in adherence with standards for trustworthy guidelines using the GRADE approach. The MAGIC Evidence Ecosystem Foundation (MAGIC) provided methodological support. The panel applied an individual patient perspective.

THE EVIDENCE

This recommendation is informed by a linked series of four systematic reviews summarising the current body of evidence for benefits and harms, as well as patient values and preferences, regarding medical cannabis or cannabinoids for chronic pain.

UNDERSTANDING THE RECOMMENDATION

The recommendation is weak because of the close balance between benefits and harms of medical cannabis for chronic pain. It reflects a high value placed on small to very small improvements in self reported pain intensity, physical functioning, and sleep quality, and willingness to accept a small to modest risk of mostly self limited and transient harms. Shared decision making is required to ensure patients make choices that reflect their values and personal context. Further research is warranted and may alter this recommendation.

Medical cannabis or cannabinoids for chronic non-cancer and cancer related pain: a systematic review and meta-analysis of randomised clinical trials

OBJECTIVE

To determine the benefits and harms of medical cannabis and cannabinoids for chronic pain.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

MEDLINE, EMBASE, AMED, PsycInfo, CENTRAL, CINAHL, PubMed, Web of Science, Cannabis-Med, Epistemonikos, and trial registries up to January 2021.

STUDY SELECTION

Randomised clinical trials of medical cannabis or cannabinoids versus any non-cannabis control for chronic pain at ≥1 month follow-up.

DATA EXTRACTION AND SYNTHESIS

Paired reviewers independently assessed risk of bias and extracted data. We performed random-effects models meta-analyses and used GRADE to assess the certainty of evidence.

RESULTS

A total of 32 trials with 5174 adult patients were included, 29 of which compared medical cannabis or cannabinoids with placebo. Medical cannabis was administered orally (n=30) or topically (n=2). Clinical populations included chronic non-cancer pain (n=28) and cancer related pain (n=4). Length of follow-up ranged from 1 to 5.5 months. Compared with placebo, non-inhaled medical cannabis probably results in a small increase in the proportion of patients experiencing at least the minimally important difference (MID) of 1 cm (on a 10 cm visual analogue scale (VAS)) in pain relief (modelled risk difference (RD) of 10% (95% confidence interval 5% to 15%), based on a weighted mean difference (WMD) of -0.50 cm (95% CI -0.75 to -0.25 cm, moderate certainty)). Medical cannabis taken orally results in a very small improvement in physical functioning (4% modelled RD (0.1% to 8%) for achieving at least the MID of 10 points on the 100-point SF-36 physical functioning scale, WMD of 1.67 points (0.03 to 3.31, high certainty)), and a small improvement in sleep quality (6% modelled RD (2% to 9%) for achieving at least the MID of 1 cm on a 10 cm VAS, WMD of -0.35 cm (-0.55 to -0.14 cm, high certainty)). Medical cannabis taken orally does not improve emotional, role, or social functioning (high certainty). Moderate certainty evidence shows that medical cannabis taken orally probably results in a small increased risk of transient cognitive impairment (RD 2% (0.1% to 6%)), vomiting (RD 3% (0.4% to 6%)), drowsiness (RD 5% (2% to 8%)), impaired attention (RD 3% (1% to 8%)), and nausea (RD 5% (2% to 8%)), but not diarrhoea; while high certainty evidence shows greater increased risk of dizziness (RD 9% (5% to 14%)) for trials with <3 months follow-up versus RD 28% (18% to 43%) for trials with ≥3 months follow-up; interaction test P=0.003; moderate credibility of subgroup effect).

CONCLUSIONS

Moderate to high certainty evidence shows that non-inhaled medical cannabis or cannabinoids results in a small to very small improvement in pain relief, physical functioning, and sleep quality among patients with chronic pain, along with several transient adverse side effects, compared with placebo. The accompanying BMJ Rapid Recommendation provides contextualised guidance based on this body of evidence. SYSTEMATIC REVIEW REGISTRATION: https://osf.io/3pwn2.

Safety and tolerability of nabiximols oromucosal spray: a review of more than 15 years" accumulated evidence from clinical trials

Introduction: Nabiximols, a cannabinoid-based oromucosal spray, is indicated as add-on therapy for symptomatic relief of spasticity in persons with multiple sclerosis (MS). This review compiles tolerability and safety data from clinical trials that investigated nabiximols for spasticity and/or chronic pain.Areas covered: Systematic searches identified 38 placebo-controlled randomized controlled trials (RCTs) or post-RCT open-label studies reporting safety data: 15 in spasticity; 16 in neuropathic pain; six in chronic cancer pain; and one in rheumatoid arthritis pain. In RCTs, discontinuation rates due to adverse events (AEs) for nabiximols and placebo were lower in spasticity studies (5.4% and 2.8%) than in neuropathic pain (12.9% and 5.3%) or cancer pain (19.5% and 16.6%) studies. The most consistently identified AEs were dizziness, nausea and fatigue in spasticity or neuropathic pain studies; and dizziness, nausea, vomiting and somnolence in cancer pain studies. Serious AE (SAE) rates for nabiximols and placebo were higher in cancer pain (21.8% and 16.9%) than in MS spasticity (4.7% vs. 0.8%) and neuropathic pain (4.1% vs. 3.1%) studies despite similar dose ranges. Treatment-related SAEs showed no particular pattern.Expert opinion: More than 15 years of investigation of nabiximols oromucosal spray in spasticity and chronic pain conditions indicates an acceptable overall safety profile.

Cannabinoids, cannabis, and cannabis-based medicine for pain management: a systematic review of randomised controlled trials

ABSTRACT

Cannabinoids, cannabis, and cannabis-based medicines (CBMs) are increasingly used to manage pain, with limited understanding of their efficacy and safety. We summarised efficacy and adverse events (AEs) of these types of drugs for treating pain using randomised controlled trials: in people of any age, with any type of pain, and for any treatment duration. Primary outcomes were 30% and 50% reduction in pain intensity, and AEs. We assessed risk of bias of included studies, and the overall quality of evidence using GRADE. Studies of <7 and >7 days treatment duration were analysed separately. We included 36 studies (7217 participants) delivering cannabinoids (8 studies), cannabis (6 studies), and CBM (22 studies); all had high and/or uncertain risk of bias. Evidence of benefit was found for cannabis <7 days (risk difference 0.33, 95% confidence interval 0.20-0.46; 2 trials, 231 patients, very low-quality evidence) and nabiximols >7 days (risk difference 0.06, 95% confidence interval 0.01-0.12; 6 trials, 1484 patients, very low-quality evidence). No other beneficial effects were found for other types of cannabinoids, cannabis, or CBM in our primary analyses; 81% of subgroup analyses were negative. Cannabis, nabiximols, and delta-9-tetrahydrocannabinol had more AEs than control. Studies in this field have unclear or high risk of bias, and outcomes had GRADE rating of low- or very low-quality evidence. We have little confidence in the estimates of effect. The evidence neither supports nor refutes claims of efficacy and safety for cannabinoids, cannabis, or CBM in the management of pain.