The analgesic properties of delta-9-tetrahydrocannabinol and codeine

UK Medical Cannabis Registry: An Analysis of Clinical Outcomes of Medicinal Cannabis Therapy for Cancer Pain

Cancer pain (CP) is a prevalent condition with limited pharmacotherapeutic options. Cannabis-based medicinal products (CBMPs) have shown analgesic effects, but their efficacy in CP remains contentious. This study aims to evaluate the change in patient-reported outcome measures (PROMs) and adverse events (AEs) in CP patients treated with CBMPs. A case series was conducted using prospectively collected clinical data from the UK Medical Cannabis Registry. Primary outcomes were the changes in the Brief Pain Inventory (BPI), pain visual analogue scale (Pain-VAS), EQ-5D-5L, Generalized Anxiety Disorder-7 (GAD-7), Patient Global Impression of Change (PGIC) and Single-Item Sleep Quality Scale (SQS) questionnaires from baseline to 1, 3, and 6 months. AEs were recorded and graded. p < 0.050 was considered statistically significant. One hundred and sixty-eight participants were included. CBMPs were associated with improvements in all pain-specific PROMs at all follow-up periods (p < 0.050). Improvements in GAD-7, SQS, and EQ-5D-5L index scores were also observed (p < 0.050). Twenty-nine AEs (17.26%) were reported by five patients (2.98%), mostly mild-to-moderate (72.41%). Although the observational design means causality cannot be established, the findings support the development of future randomized controlled trials into CP management with CBMPs.

The Role of Cannabinoids and the Endocannabinoid System in the Treatment and Regulation of Nausea and Vomiting

Despite using the recommended anti-emetic treatments, control of nausea and vomiting is still an unmet need for cancer patients undergoing chemotherapy treatment. Few properly controlled clinical trials have evaluated the potential of exogenously administered cannabinoids or manipulations of the endogenous cannabinoid (eCB) system to treat nausea and vomiting. In this chapter, we explore the pre-clinical and human clinical trial evidence for the potential of exogenous cannabinoids and manipulations of the eCB system to reduce nausea and vomiting. Although there are limited high-quality human clinical trials, pre-clinical evidence suggests that cannabinoids and manipulations of the eCB system have anti-nausea/anti-emetic potential. The pre-clinical anti-nausea/anti-emetic evidence highlights the need for further evaluation of cannabinoids and manipulations of eCBs and other fatty acid amides in clinical trials.

Adverse events associated with the use of cannabis-based products in people living with cancer: a systematic scoping review

PURPOSE

To summarise the extent and type of evidence in relation to adverse events (AEs) associated with the use of cannabis-based products (CBP) in people living with cancer.

METHODS

The Joanna Briggs Institute (JBI) methodology for scoping reviews was applied. A search was performed in MEDLINE (Ovid), Embase (Ovid), CINAHL (EBSCOhost), Scopus, Web of Science Core Collections and AMED (Ovid) from their inception to 7 May 2023. Primary studies reporting AEs associated with any form of natural or synthetic CBP use in any cancer care setting and location were included.

RESULTS

One hundred fifty-two studies were included, with the most prevalent being randomised controlled trials (RCTs) (n = 61), followed by non-randomised controlled trials (n = 26) and case reports (n = 23). CBP was mainly used in gastrointestinal, liver, or peritoneal cancer (n = 98) and haematological or lymphoid cancer (n = 92), primarily to manage nausea and vomiting (n = 78) and cancer pain (n = 37). The most common CBP ingredients were combinations of THC and CBD (n = 69), synthetic THC (n = 47), single compounds of THC (n = 42) and CBD (n = 16) with diverse forms, administration routes and doses. The primary methods of administration were oral (n = 94) and inhalation (n = 54). A broad range of AEs were reported; the most common were related to the nervous system (n = 118), psychiatric (n = 101) and gastrointestinal system (n = 81). Diverse patient characteristics, significant under-reporting and low-quality reporting were observed in many studies.

CONCLUSIONS

More rigorous research designs that prioritise comprehensive, standardised reporting of AEs and CBP use are required to fully elucidate the safety profile of CBP use in cancer care.

Adverse Ocular Impact and Emerging Therapeutic Potential of Cannabis and Cannabinoids: A Narrative Review

Cannabis is the most used drug worldwide with an estimated 219 million users. This narrative review aims to explore the adverse effects and therapeutic applications of cannabis and cannabinoids on the eye, given its growing clinical and non-clinical uses. The current literature reports several adverse ocular effects of cannabis and cannabinoids, including eyelid tremor, ptosis, reduced corneal endothelial cell density, dry eyes, red eyes, and neuro-retinal dysfunction. Cannabinoids may transiently impair night vision, depth perception, binocular and monocular contrast sensitivity, and dynamic visual acuity. Cannabinoids are not currently considered a first-line treatment option for any ocular conditions. Δ-9-tetrahydrocannabinol been shown to result in short-term intraocular pressure reduction, but insufficient evidence to support its use in treating glaucoma exists. Potential therapeutic applications of cannabinoids include their use as a second-line agent for treatment-refractory blepharospasm, for dry eye disease given corneal anti-inflammatory properties, and for suppression of pendular nystagmus in individuals with multiple sclerosis, which all necessitate further research for informed clinical practices.

The Role of Cannabinoids in Advancing Cancer Treatment: Insights from Evidence-Based Medicine

PURPOSE OF REVIEW

This document critically examines the role of cannabinoids in cancer care during an era marked by rapid advancements in oncology and changing perceptions on cannabis. It traces the historical context of cannabis in medicinal use, navigating its journey from widespread acceptance, subsequent criminalization, to its resurgence in modern therapeutic applications, particularly within the framework of Evidence-Based Medicine (EBM).

RECENT FINDINGS

Anchored in EBM principles, this study synthesizes current research from clinical trials, systematic reviews, and meta-analyses to evaluate the efficacy and safety of cannabinoids in oncology. The focus is on their palliative effects, considering the nuances of effectiveness, risk assessment, and challenges inherent in translating these findings into clinical guidelines. The study seeks to bridge the gap between scientific research and clinical practice, offering insights to inform future oncological therapies and symptom management strategies involving cannabinoids. The potential benefits and risks of cannabinoid use in cancer treatment are assessed to guide clinicians and researchers in developing comprehensive, evidence-based approaches to patient care.

Cannabinoids as Antibacterial Agents: A Systematic and Critical Review of In Vitro Efficacy Against Streptococcus and Staphylococcus

BACKGROUND

Two major bacterial pathogens, Staphylococcus aureus and Streptococcus pyogenes, are becoming increasingly antibiotic-resistant. Despite the urgency, only a few new antibiotics have been approved to address these infections. Although cannabinoids have been noted for their antibacterial properties, a comprehensive review of their effects on these bacteria has been lacking.

OBJECTIVE

This systematic review examines the antibacterial activity of cannabinoids against S. aureus, including methicillin-resistant S. aureus (MRSA) and vancomycin-resistant S. aureus (VRSA) strains, and S. pyogenes.

METHODS

Databases, including CINAHL, Cochrane, Medline, Scopus, Web of Science, and LILACS, were searched. Of 3510 records, 24 studies met the inclusion criteria, reporting on the minimum inhibitory concentration (MIC) and minimum bactericidal concentration of cannabinoids.

RESULTS

Cannabidiol (CBD) emerged as the most effective cannabinoid, with MICs ranging from 0.65 to 32 mg/L against S. aureus, 0.5 to 4 mg/L for MRSA, and 1 to 2 mg/L for VRSA. Other cannabinoids, such as cannabichromene, cannabigerol (CBG), and delta-9-tetrahydrocannabinol (Δ9-THC), also exhibited significant antistaphylococcal activity. CBD, CBG, and Δ9-THC also showed efficacy against S. pyogenes, with MICs between 0.6 and 50 mg/L. Synergistic effects were observed when CBD and essential oils from Cannabis sativa when combined with other antibacterial agents.

CONCLUSION

Cannabinoids' antibacterial potency is closely linked to their structure-activity relationships, with features like the monoterpene region, aromatic alkyl side chain, and aromatic carboxylic groups enhancing efficacy, particularly in CBD and its cyclic forms. These results highlight the potential of cannabinoids in developing therapies for resistant strains, though further research is needed to confirm their clinical effectiveness.

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.

Integrative Therapies in Cancer Care: An Update on the Guidelines

INTRODUCTION

ASCO and the Society for Integrative Oncology have collaborated to develop guidelines for the application of integrative approaches in the management of anxiety, depression, fatigue and use of cannabinoids and cannabis in patients with cancer. These guidelines provide evidence-based recommendations to improve outcomes and quality of life by enhancing conventional cancer treatment with integrative modalities.

METHODS

All studies that informed the guideline recommendations were reviewed by an Expert Panel which was made up of a patient advocate, an ASCO methodologist, oncology providers, and integrative medicine experts. Panel members reviewed each trial for quality of evidence, determined a grade quality assessment label, and concluded strength of recommendations.

RESULTS

Strong recommendations for management of cancer fatigue during treatment were given to both in-person or web-based mindfulness-based stress reduction, mindfulness-based cognitive therapy, and tai chi or qigong. Strong recommendations for management of cancer fatigue after cancer treatment were given to mindfulness-based programs. Clinicians should recommend against using cannabis or cannabinoids as a cancer-directed treatment unless within the context of a clinical trial. The recommended modalities for managing anxiety included Mindfulness-Based Interventions (MBIs), yoga, hypnosis, relaxation therapies, music therapy, reflexology, acupuncture, tai chi, and lavender essential oils. The strongest recommendation in the guideline is that MBIs should be offered to people with cancer, both during active treatment and post-treatment, to address depression.

CONCLUSION

The evidence for integrative interventions in cancer care is growing, with research now supporting benefits of integrative interventions across the cancer care continuum.

Opioid analgesics for nociceptive cancer pain: A comprehensive review

Pain is one of the most burdensome symptoms in people with cancer, and opioid analgesics are considered the mainstay of cancer pain management. For this review, the authors evaluated the efficacy and toxicities of opioid analgesics compared with placebo, other opioids, nonopioid analgesics, and nonpharmacologic treatments for background cancer pain (continuous and relatively constant pain present at rest), and breakthrough cancer pain (transient exacerbation of pain despite stable and adequately controlled background pain). They found a paucity of placebo-controlled trials for background cancer pain, although tapentadol or codeine may be more efficacious than placebo (moderate-certainty to low-certainty evidence). Nonsteroidal anti-inflammatory drugs including aspirin, piroxicam, diclofenac, ketorolac, and the antidepressant medicine imipramine, may be at least as efficacious as opioids for moderate-to-severe background cancer pain. For breakthrough cancer pain, oral transmucosal, buccal, sublingual, or intranasal fentanyl preparations were identified as more efficacious than placebo but were more commonly associated with toxicities, including constipation and nausea. Despite being recommended worldwide for the treatment of cancer pain, morphine was generally not superior to other opioids, nor did it have a more favorable toxicity profile. The interpretation of study results, however, was complicated by the heterogeneity in the study populations evaluated. Given the limited quality and quantity of research, there is a need to reappraise the clinical utility of opioids in people with cancer pain, particularly those who are not at the end of life, and to further explore the effects of opioids on immune system function and quality of life in these individuals.

Current status of Complementary and Alternative Medicine Interventions in the Management of Pancreatic Cancer - An Overview

OPINION STATEMENT

Pancreatic cancer (PC) remains the deadliest cancer worldwide. Most patients are diagnosed at the advanced or metastatic stage, leading to a poor prognosis. Awareness of the limitations of current therapy and accompanying pain, depression, malnutrition, and side effects of chemoradiotherapy may lead patients and physicians towards complementary and alternative medicine (CAM). CAM refers to a diverse set of medical and healthcare practices, products, and systems that are not part of conventional Western medicine. Despite the low-quality evidence supporting the efficacy of these methods, they remain appealing due to patients' beliefs, fear of death, and the slow development of conventional therapy. Hence, the possibility of using natural products for pancreatic cancer is increasing. CAM options such as: medical cannabis, plants, fungi, herbal formulas, and injections, which originate primarily from traditional Chinese or Japanese medicine i.e. Curcuma longa, Panax ginseng, Poria cocos, Hochuekkito, Juzentaihoto, and Rikkunshito, Shi-quan-da-bu-tang/TJ-48, Huang-qin-tang, Shuangbai San, Wen Jing Zhi Tong Fang, Xiang-Sha-Liu-jun-zi-tang, Aidi injection, Brucea javanica oil emulsion/Yadanziyouru injection, Compound Kushen injection, Huachansu injection, Kangai injection and Kanglaite injections are becoming promising candidates for the management of pancreatic cancer. The abovementioned substances/medications are the most popular or potentially effective in PC treatment and consequently CAM-based adjuvant therapy through improving patients' quality of life, might be a useful addition in the treatment of pancreatic cancer patients.

The Exploration of Cannabis and Cannabinoid Therapies for Migraine

PURPOSE OF REVIEW

There is increasing interest in the use of cannabis and cannabinoid therapies (CCT) by the general population and among people with headache disorders, which results in a need for healthcare professionals to be well versed with the efficacy and safety data. In this manuscript, we review cannabis and cannabinoid terminology, the endocannabinoid system and its role in the central nervous system (CNS), the data on efficacy, safety, tolerability, and potential pitfalls associated with use in people with migraine and headache disorders. We also propose possible mechanisms of action in headache disorders and debunk commonly held myths about its use.

RECENT FINDINGS

Preliminary studies show that CCT have evidence for the management of migraine. While this evidence exists, further randomized, controlled studies are needed to better support its clinical use. CCT can be considered an integrative treatment added to mainstream medicine for people with migraine who are refractory to treatment and/or exhibit disability and/or interest in trying these therapies. Further studies are warranted to specify appropriate formulation, dosage, and indication(s). Although not included in guidelines or the AHS 2021 Consensus Statement on migraine therapies, with the legalization of CCT for medical or unrestricted use across the USA, recent systematic reviews highlighting the preliminary evidence for its use in migraine, it is vital for clinicians to be well versed in the efficacy, safety, and clinical considerations for their use. This review provides information which can help people with migraine and clinicians who care for them make mutual, well-informed decisions on the use of cannabis and cannabinoid therapies for migraine based on the existing data.

Tetrahydrocannabinols: potential cannabimimetic agents for cancer therapy

Tetrahydrocannabinols (THCs) antagonize the CB1 and CB2 cannabinoid receptors, whose signaling to the endocannabinoid system is essential for controlling cell survival and proliferation as well as psychoactive effects. Most tumor cells express a much higher level of CB1 and CB2; THCs have been investigated as potential cancer therapeutic due to their cannabimimetic properties. To date, THCs have been prescribed as palliative medicine to cancer patients but not as an anticancer modality. Growing evidence of preclinical research demonstrates that THCs reduce tumor progression by stimulating apoptosis and autophagy and inhibiting two significant hallmarks of cancer pathogenesis: metastasis and angiogenesis. However, the degree of their anticancer effects depends on the origin of the tumor site, the expression of cannabinoid receptors on tumor cells, and the dosages and types of THC. This review summarizes the current state of knowledge on the molecular processes that THCs target for their anticancer effects. It also emphasizes the substantial knowledge gaps that should be of concern in future studies. We also discuss the therapeutic effects of THCs and the problems that will need to be addressed in the future. Clarifying unanswered queries is a prerequisite to translating the THCs into an effective anticancer regime.

Should oncologists trust cannabinoids?

Cannabis enjoyed a "golden age" as a medicinal product in the late 19th, early 20th century, but the increased risk of overdose and abuse led to its criminalization. However, the 21st century have witnessed a resurgence of interest and a large body of literature regarding the benefits of cannabinoids have emerged. As legalization and decriminalization have spread around the world, cancer patients are increasingly interested in the potential utility of cannabinoids. Although eager to discuss cannabis use with their oncologist, patients often find them to be reluctant, mainly because clinicians are still not convinced by the existing evidence-based data to guide their treatment plans. Physicians should prescribe cannabis only if a careful explanation can be provided and follow up response evaluation ensured, making it mandatory for them to be up to date with the positive and also negative aspects of the cannabis in the case of cancer patients. Consequently, this article aims to bring some clarifications to clinicians regarding the sometimes-confusing various nomenclature under which this plant is mentioned, current legislation and the existing evidence (both preclinical and clinical) for the utility of cannabinoids in cancer patients, for either palliation of the associated symptoms or even the potential antitumor effects that cannabinoids may have.

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.

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.

Medical Cannabis for Chronic Nonmalignant Pain Management

PURPOSE OF REVIEW

Cannabis has been used since ancient times for medical and recreational research. This review article will document the validity of how medical cannabis can be utilized for chronic nonmalignant pain management.

RECENT FINDINGS

Current cannabis research has shown that medical cannabis is indicated for symptom management for many conditions not limited to cancer, chronic pain, headaches, migraines, and psychological disorders (anxiety and post-traumatic stress disorder). Δ9-Tetrahydrocannabinol (THC) and cannabidiol (CBD) are active ingredients in cannabis that modulate a patient's symptoms. These compounds work to decrease nociception and symptom frequency via the endocannabinoid system. Research regarding pain management is limited within the USA as the Drug Enforcement Agency (DEA) classifies it as a schedule one drug. Few studies have found a limited relationship between chronic pain and medical cannabis use. A total of 77 articles were selected after a thorough screening process using PubMed and Google Scholar. This paper demonstrates that medical cannabis use provides adequate pain management. Patients suffering from chronic nonmalignant pain may benefit from medical cannabis due to its convenience and efficacy.

MASCC guideline: cannabis for cancer-related pain and risk of harms and adverse events

BACKGROUND

Approximately 18% of patients with cancer use cannabis at one time as palliation or treatment for their cancer. We performed a systematic review of randomized cannabis cancer trials to establish a guideline for its use in pain and to summarize the risk of harm and adverse events when used for any indication in cancer patients.

METHODS

A systematic review of randomized trials with or without meta-analysis was carried out from MEDLINE, CCTR, Embase, and PsychINFO. The search involved randomized trials of cannabis in cancer patients. The search ended on November 12, 2021. The Jadad grading system was used for grading quality. Inclusion criteria for articles were randomized trials or systematic reviews of randomized trials of cannabinoids versus either placebo or active comparator explicitly in adult patients with cancer.

RESULTS

Thirty-four systematic reviews and randomized trials met the eligibility criteria for cancer pain. Seven were randomized trials involving patients with cancer pain. Two trials had positive primary endpoints, which could not be reproduced in similarly designed trials. High-quality systematic reviews with meta-analyses found little evidence that cannabinoids are an effective adjuvant or analgesic to cancer pain. Seven systematic reviews and randomized trials related to harms and adverse events were included. There was inconsistent evidence about the types and levels of harm patients may experience when using cannabinoids.

CONCLUSION

The MASCC panel recommends against the use of cannabinoids as an adjuvant analgesic for cancer pain and suggests that the potential risk of harm and adverse events be carefully considered for all cancer patients, particularly with treatment with a checkpoint inhibitor.

Cannabis use amongst tinnitus patients: consumption patterns and attitudes

BACKGROUND

Tinnitus has a significant impact on quality of life and causes considerable psychological distress. Cannabis is known to modulate neuron hyperexcitability, provide protection against auditory damage, and has been used for treatment for many diseases which have physiological similarities with tinnitus. The objective of this study was to survey patients presenting with tinnitus regarding their perspectives and usage patterns of cannabis.

METHODS

Patients with a primary presenting complaint of tinnitus in a tertiary neuro-otology clinic completed a 18-item questionnaire assessing perception, attitudes, and cannabis usage patterns.

RESULTS

Forty five patients completed the survey (mean age: 54.5 years, 31 females and 14 males). Overall, 96% of patients reported that they would consider cannabis as treatment for their tinnitus. Patients considered cannabis use for auditory symptoms (91%), and symptoms related to their tinnitus, such as emotional complaints (60%), sleep disturbances (64%), and functional disturbances (56%). 36% of patients had previously used cannabis and 22% of patients reported cannabis use at the time of the study. 80% of patients that were actively using cannabis reported that it helped with tinnitus-related symptoms, such as dizziness, anxiety, bodily pain, and sleep disturbances. Most patients would prefer to use edibles (62%), tablet (58%) and cream (47%) formulations of cannabis. Patients were concerned about the cost (29%), potential physical health implications (53%) and psychosocial side effects (60%) of cannabis. Over half of patients learned about cannabis from a friend or family member and only 22% of patients learned about cannabis from a physician or nurse.

CONCLUSION

Cannabis use is common amongst patients with tinnitus and current users of cannabis reported that it helped with their symptoms. Most patients would consider its use as a potential treatment to alleviate their tinnitus-related symptoms and are interested in learning more regarding its use. By understanding how cannabis is perceived by tinnitus patients, healthcare providers can provide appropriate patient education.

[Use of dronabinol in the treatment of resistant neuropathic pain: Feedback from patients followed in a multidisciplinary pain center]

INTRODUCTION

Dronabinol is a drug composed of synthetic delta-9-tetrahydrocannabinol. In France, dronabinol requires a named Temporary Utilisation Authorisation (TUA), for the treatment of refractory neuropathic pain. Few data currently exist concerning its efficacy and tolerance. We present our feedback on its use for chronic pain patients, the multidisciplinary supervision and the monitoring set up by the clinical pharmacist.

METHOD

This retrospective monocentric study presents Patients Global Impression of Change and tolerance data from patients treated with dronabinol in a pain center between October 2020 and July 2021. We present their satisfaction towards the care process.

RESULTS

Nineteen patients were treated with dronabinol during the study period. - The clinical pharmacist issued 180 advices for patients and doctors. Patients reported a positive impact of the telephone follow-up carried out by the clinical pharmacist. - 75% (n=9/12) of patients who continued treatment for more than 3 months reported improvement in their health. - 74% (n=14/19) of patients had at least one adverse event, six patients needed to discontinue the treatment.

DISCUSSION-CONCLUSION

Dronabinol represents an alternative that can improve the quality of life of some patients suffering from refractory neuropathic pain. Nevertheless, as with any medicine, its initiation requires a rigorous evaluation of the benefit-risk balance. The close collaboration between the physician and the clinical pharmacist allows a secure management patients and makes this complex drug circuit easer.

Cannabis in Palliative Care: A Systematic Review of Current Evidence

CONTEXT

Palliative care aims to improve the quality of life in patients with incurable illness. Medicinal cannabis (MC) has been used in the palliative care setting to address multiple symptoms in patients.

OBJECTIVES

To evaluate the full scope of available literature investigating the effects and potential harms of MC on symptom management and quality of life in palliative care.

METHODS

PubMed, Embase, The Cochrane Library and clinicaltrials.gov were searched for eligible articles, published between 1960 and September 9, 2021. Quality of the evidence was assessed in accordance with Grading of Recommendations, Assessment, Development and Evaluations. Risk of bias was assessed using the RoB 2 tool for randomised controlled trials and the Risk of Bias in Non-randomized Studies-of Interventions (ROBINS-I) tool for non-randomized trials.

RESULTS

Fifty-two studies (20 randomised; 32 non-randomised) with 4786 participants diagnosed with cancer (n = 4491), dementia (n = 43), AIDS (n = 235), spasticity (n = 16), NORSE syndrome (n = 1) were included. The quality of evidence was 'very low' or 'low' for all studies, and low for only two randomised controlled trials. Positive treatment effects (statistical significance with P < 0.05) were seen for some MC products in pain, nausea and vomiting, appetite, sleep, fatigue, chemosensory perception and paraneoplastic night sweats in patients with cancer, appetite and agitation in patients with dementia and appetite, nausea and vomiting in patients with AIDS. Meta-analysis was unable to be performed due to the wide range of cannabis products used and the heterogeneity of the study outcomes.

CONCLUSION

While positive treatment effects have been reported for some MC products in the palliative care setting, further high quality evidence is needed to support recommendations for its use in clinical practice.

Use of Cannabis and Cannabinoids for Treatment of Cancer

The endocannabinoid system (ECS) is an ancient homeostasis mechanism operating from embryonic stages to adulthood. It controls the growth and development of many cells and cell lineages. Dysregulation of the components of the ECS may result in uncontrolled proliferation, adhesion, invasion, inhibition of apoptosis and increased vascularization, leading to the development of various malignancies. Cancer is the disease of uncontrolled cell division. In this review, we will discuss whether the changes to the ECS are a cause or a consequence of malignization and whether different tissues react differently to changes in the ECS. We will discuss the potential use of cannabinoids for treatment of cancer, focusing on primary outcome/care-tumor shrinkage and eradication, as well as secondary outcome/palliative care-improvement of life quality, including pain, appetite, sleep, and many more factors. Finally, we will complete this review with the chapter on sex- and gender-specific differences in ECS and response to cannabinoids, and equality of the access to treatments with cannabinoids.

Practical Considerations for the Use of Cannabis in Cancer Pain Management—What a Medical Oncologist Should Know

Pain is a highly debilitating emotional and sensory experience that significantly affects quality of life (QoL). Numerous chronic conditions, including cancer, are associated with chronic pain. In the setting of malignancy, pain can be a consequence of the tumor itself or of life-saving interventions, including surgery, chemotherapy, and radiotherapy. Despite significant pharmacological advances and awareness campaigns, pain remains undertreated in one-third of patients. To date, opioids have been the mainstay of cancer pain management. The problematic side effects and unsatisfactory pain relief of opioids have revived patients’ and physicians’ interest in finding new solutions, including cannabis and cannabinoids. The medical use of cannabis has been prohibited for decades, and it remains in Schedule 1 of the Misuse of Drugs Regulations. Currently, the legal context for its usage has become more permissive. Various preclinical and observational studies have aimed to prove that cannabinoids could be effective in cancer pain management. However, their clinical utility must be further supported by high-quality clinical trials.

Medical cannabinoids: a pharmacology-based systematic review and meta-analysis for all relevant medical indications

BACKGROUND

Medical cannabinoids differ in their pharmacology and may have different treatment effects. We aimed to conduct a pharmacology-based systematic review (SR) and meta-analyses of medical cannabinoids for efficacy, retention and adverse events.

METHODS

We systematically reviewed (registered at PROSPERO: CRD42021229932) eight databases for randomized controlled trials (RCTs) of dronabinol, nabilone, cannabidiol and nabiximols for chronic pain, spasticity, nausea /vomiting, appetite, ALS, irritable bowel syndrome, MS, Chorea Huntington, epilepsy, dystonia, Parkinsonism, glaucoma, ADHD, anorexia nervosa, anxiety, dementia, depression, schizophrenia, PTSD, sleeping disorders, SUD and Tourette. Main outcomes and measures included patient-relevant/disease-specific outcomes, retention and adverse events. Data were calculated as standardized mean difference (SMD) and ORs with confidence intervals (CI) via random effects. Evidence quality was assessed by the Cochrane Risk of Bias and GRADE tools.

RESULTS

In total, 152 RCTs (12,123 participants) were analysed according to the type of the cannabinoid, outcome and comparator used, resulting in 84 comparisons. Significant therapeutic effects of medical cannabinoids show a large variability in the grade of evidence that depends on the type of cannabinoid. CBD has a significant therapeutic effect for epilepsy (SMD - 0.5[CI - 0.62, - 0.38] high grade) and Parkinsonism (- 0.41[CI - 0.75, - 0.08] moderate grade). There is moderate evidence for dronabinol for chronic pain (- 0.31[CI - 0.46, - 0.15]), appetite (- 0.51[CI - 0.87, - 0.15]) and Tourette (- 1.01[CI - 1.58, - 0.44]) and moderate evidence for nabiximols on chronic pain (- 0.25[- 0.37, - 0.14]), spasticity (- 0.36[CI - 0.54, - 0.19]), sleep (- 0.24[CI - 0.35, - 0.14]) and SUDs (- 0.48[CI - 0.92, - 0.04]). All other significant therapeutic effects have either low, very low, or even no grade of evidence. Cannabinoids produce different adverse events, and there is low to moderate grade of evidence for this conclusion depending on the type of cannabinoid.

CONCLUSIONS

Cannabinoids are effective therapeutics for several medical indications if their specific pharmacological properties are considered. We suggest that future systematic studies in the cannabinoid field should be based upon their specific pharmacology.

Cannabis as a potential compound against various malignancies, legal aspects, advancement by exploiting nanotechnology and clinical trials

Various preclinical and clinical studies exhibited the potential of cannabis against various diseases, including cancer and related pain. Subsequently, many efforts have been made to establish and develop cannabis-related products and make them available as prescription products. Moreover, FDA has already approved some cannabis-related products, and more advancement in this aspect is still going on. However, the approved product of cannabis is in oral dosage form, which exerts various limitations to achieve maximum therapeutic effects. A considerable translation is on a hike to improve bioavailability, and ultimately, the therapeutic efficacy of cannabis by the employment of nanotechnology. Besides the well-known psychotropic effects of cannabis upon the use at high doses, literature has also shown the importance of cannabis and its constituents in minimising the lethality of cancer in the preclinical models. This review discusses the history of cannabis, its legal aspect, safety profile, the mechanism by which cannabis combats with cancer, and the advancement of clinical therapy by exploiting nanotechnology. A brief discussion related to the role of cannabinoid in various cancers has also been incorporated. Lastly, the information regarding completed and ongoing trials have also been elaborated.

Cannabinoid consumption among cancer patients receiving systemic anti-cancer treatment in the Netherlands

PURPOSE

Despite the inconclusiveness regarding health effects of cannabinoids among cancer patients, studies from non-European countries suggest that the medical-intended consumption of such products by this patient group is significant. The current study analyses cannabinoid usage among oncology patients receiving systemic treatment in the Netherlands.

METHODS

The current study included adult patients receiving intravenous systemic therapy at Maastricht Comprehensive Cancer Centre, for a solid malignancy. Participants were asked to complete an anonymous questionnaire including questions on demographic variables, clinical variables and cannabinoid consumption.

RESULTS

A total of 153 patients with solid cancer were included in this study. Almost 25% reported usage of cannabinoids for medical purposes, with 15% of the patients currently using the substance. Additionally, 18% of non-users considered future medical usage. In 48% of the cases, consumption was reported by the oncologist. The proposed anti-cancer effect was reported by 46% of the users as motivation for consumption. Current users were mainly palliative patients and 54% of the users were undergoing immunotherapy. Intention of treatment and type of therapy were predictive factors for consumption. Cannabinoid-oil was the most frequently used way of consumption.

CONCLUSION

This study underlines the high number of cannabinoid users among oncology patients in the Netherlands in presumed absence of clinical guidance. It highlights the essence of a pro-active role of the clinician, assessing cannabinoid usage and educating the patients on the most recent evidence regarding its potential benefits and risks. Further studies on clinical decision making and efficacy of cannabinoids are recommended, to improve clinical guidance.

The Role of Cannabis, Cannabidiol and Other Cannabinoids in Chronic Pain. The Perspective of Physicians

Currently, there is a renewed interest in treatments with medical cannabis and cannabinoids. Based on an increasing number of publications over the last decades that permitted new insights into mechanisms, efficacy and safety of cannabinoids, the use of cannabinergic medications is authorised in an increasing number of European and non-European countries. The alleviation of chronic, painful conditions is, since thousands of years, one of the primary reasons for the use of cannabis. Depending on the country, a wide range of medicinal cannabis preparations are available:ranging from defined cultivars of medical cannabis, mainly varying in their THC:CBD ratio, that are inhaled or taken as whole plant extracts,to highly purified single cannabinoids, such as delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD),or mixtures of two enriched extracts, standardised to a 1:1 ratio of THC:CBD (nabiximols). Although conflicting opinions continue to exist, the majority of reviews in the past concluded that medical cannabis and cannabinoids play a significant role in the management of pain. Surprisingly, systematic studies to date do not support an "entourage effect" of the other plant constituents of cannabis (mainly terpenoids) in treatment of chronic pain. An emerging cannabinoid is CBD which is the only cannabinergic medication available at present that does not cause the typical "cannabis high"; it is not a "controlled substance". However, despite years of research, there is either no study or no well-conducted, head-to-head, comparison available between different cannabis cultivars, between pure cannabinoids, and between pure cannabinoids and extracts. It remains unanswered which is the optimal treatment approach.

The Effectiveness and Safety of Medical Cannabis for Treating Cancer Related Symptoms in Oncology Patients

The use of medical cannabis (MC) to treat cancer-related symptoms is rising. However, there is a lack of long-term trials to assess the benefits and safety of MC treatment in this population. In this work, we followed up prospectively and longitudinally on the effectiveness and safety of MC treatment. Oncology patients reported on multiple symptoms before and after MC treatment initiation at one-, three-, and 6-month follow-ups. Oncologists reported on the patients' disease characteristics. Intention-to-treat models were used to assess changes in outcomes from baseline. MC treatment was initiated by 324 patients and 212, 158 and 126 reported at follow-ups. Most outcome measures improved significantly during MC treatment for most patients (p < 0.005). Specifically, at 6 months, total cancer symptoms burden declined from baseline by a median of 18%, from 122 (82-157) at baseline to 89 (45-138) at endpoint (-18.98; 95%CI= -26.95 to -11.00; p < 0.001). Reported adverse effects were common but mostly non-serious and remained stable during MC treatment. The results of this study suggest that MC treatment is generally safe for oncology patients and can potentially reduce the burden of associated symptoms with no serious MC-related adverse effects.

Revision of Pharmacological Treatment Recommendations for Cancer Pain: Clinical Guidelines from the Japanese Society of Palliative Medicine

Background: Pain is one of the most common symptoms in cancer patients. The Japanese Society for Palliative Medicine (JSPM) first published its clinical guidelines for the management of cancer pain in 2010. Since then, more research on cancer pain management has been reported, and new drugs have become available in Japan. Thus, the JSPM has now revised the clinical guidelines using a validated methodology. Methods: This guideline was developed through a systematic review, discussion, and the Delphi method, following a formal guideline development process. Results: Thirty-five recommendations were created: 19 for the pharmacological management of cancer pain, 6 for the management of opioid-induced adverse effects, and 10 for pharmacological treatment procedures. Due to the lack of evidence that directly addressed our clinical questions, most of the recommendations had to be based on consensus among committee members and other guidelines. Discussion: It is critical to continue to build high-quality evidence in cancer pain management, and revise these guidelines accordingly.

Perspectives on Challenges in Cannabis Drug Delivery Systems: Where Are We?

Cannabis and its natural derivatives have emerged as promising therapeutics for multiple pathological and nonpathological medical conditions. For example, cannabinoids, the most popular and biologically active chemicals in cannabis, aid in many clinical ailments, including pain, inflammation, epilepsy, sleep disturbances or insomnia, multiple sclerosis, anorexia, schizophrenia, neurodegenerative diseases, anti-nausea, and most importantly, cancer. Despite the comprehensive benefits, certain aspects of cannabis present unique challenges in the medical cannabis landscape. Recent studies have highlighted the inherent challenges associated with cannabinoids' formulation like low solubility, rapid metabolism, poor bioavailability, and erratic pharmacokinetics - all of which contribute to the limited efficacy of cannabinoids. Several efforts are underway to address the bottlenecks and modify the formulations along with the delivery systems to achieve greater solubility/bioavailability, potency, and efficacy in treatment settings while minding the necessary standards for purity associated with the pharmaceutical industry. The current article presents a perspective on (1) a working knowledge of cannabinoids and their mechanisms of action, (2) the landscape of using medicinal cannabis for cancer-related medical conditions along with adversities, (3) current approaches, formulations, and challenges in medicinal cannabis delivery systems (oral, transdermal, pulmonary, and transmucosal), and lastly, (4) emerging approaches to improve delivery systems.

The Management of Cancer Symptoms and Treatment-Induced Side Effects With Cannabis or Cannabinoids

Cannabis and cannabinoids are increasingly being accessed and used by patients with advanced cancer for various symptoms and general quality of life. Specific symptoms of pain, nausea and vomiting, loss of appetite and cachexia, anxiety, sleep disturbance, and medical trauma are among those that have prompted patients with cancer to use cannabis. This conference report from the National Cancer Institute's "Cannabis, Cannabinoid and Cancer Research Symposium" on the topic of "Cancer Symptom/Treatment Side Effect Management" is an expert perspective of cannabis intervention for cancer and cancer treatment-related symptoms. The purpose of the symposium was to identify research gaps, describe the need for high-quality randomized prospective studies of medical cannabis for palliative care in patients with cancer, and evaluate the impact of medical cannabis on cancer survivors' quality of life. Further, education of clinicians and affiliated health-care providers in guiding cancer patients in using cannabis for cancer care would benefit patients. Together, these steps will further aid in refining the use of cannabis and cannabinoids for symptom palliation and improve safety and efficacy for patients.

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.

Cancer Initiation, Progression and Resistance: Are Phytocannabinoids from Cannabis sativa L. Promising Compounds?

Cannabis sativa L. is a source of over 150 active compounds known as phytocannabinoids that are receiving renewed interest due to their diverse pharmacologic activities. Indeed, phytocannabinoids mimic the endogenous bioactive endocannabinoids effects through activation of CB1 and CB2 receptors widely described in the central nervous system and peripheral tissues. All phytocannabinoids have been studied for their protective actions towards different biological mechanisms, including inflammation, immune response, oxidative stress that, altogether, result in an inhibitory activity against the carcinogenesis. The role of the endocannabinoid system is not yet completely clear in cancer, but several studies indicate that cannabinoid receptors and endogenous ligands are overexpressed in different tumor tissues. Recently, in vitro and in vivo evidence support the effectiveness of phytocannabinoids against various cancer types, in terms of proliferation, metastasis, and angiogenesis, actions partially due to their ability to regulate signaling pathways critical for cell growth and survival. The aim of this review was to report the current knowledge about the action of phytocannabinoids from Cannabis sativa L. against cancer initiation and progression with a specific regard to brain, breast, colorectal, and lung cancer as well as their possible use in the therapies. We will also report the known molecular mechanisms responsible for such positive effects. Finally, we will describe the actual therapeutic options for Cannabis sativa L. and the ongoing clinical trials.

State of the science: cannabis and cannabinoids in palliative medicine-the potential

Cannabinoids are chemicals derived naturally from the cannabis plant or are synthetically manufactured. They interact directly with cannabinoid receptors or share chemical similarity with endocannabinoids (or both). Within palliative medicine, cannabinoid receptors (CB1 and CB2) may modulate some cancer symptoms: appetite, chemotherapy-induced nausea and vomiting, and mood, pain and sleep disorders. Opioid and cannabinoid receptors have overlapping neuroanatomical receptor distribution, particularly at the dorsal horn, dorsal striatum and locus coeruleus. They have a favourable safety profile compared with opioids, and cannabis-based medicines help chronic pain. While cannabidiol (CBD) has anti-inflammatory properties, tetrahydrocannabinol (THC) is the psychoactive substance for issues such as mood and sleep. Nabiximols (Sativex), a CBD:THC combination, is Food and Drug Administration approved for some multiple sclerosis symptoms and epilepsy. There has been a swift societal evolution in attitudes about use of cannabis and cannabinoid medicines for chronic pain. In the USA, 33 states have now legalised prescription-based medical cannabis for several medical conditions; Canada has had legislation since 2001 authorising medical use. The European Union (EU) recently declared all EU citizens must have access to medical cannabis over the next 4 years. The integration into medicine and routine clinical use of cannabis is fraught with information gaps, regulatory issues and scarcity of research. Each patient should have a comprehensive assessment and risk-benefit discussion before any cannabis-based intervention to avoid possible complications such as hallucinations, psychosis and potential cardiac harm.

Aggressive Driving Behaviours in Cannabis Users. The Influence of Consumer Characteristics

This study analysed dangerous driving behaviours in twenty young occasional cannabis users through objective and self-reported data, studying the relationship between the two aspects. Visual function was assessed in a baseline session and after smoking cannabis, as well as speed-related behaviour in a driving simulator. The participants responded to questionnaires on sociodemographic factors, their consumption profile, and the incidence of dangerous behaviours (Dula Dangerous Driving Index; DDDI). After cannabis use, the results revealed a significant deterioration in visual function. In terms of speed management, they showed significantly greater acceleration force in the two different sections of the route, and they drove significantly faster. Our correlations indicate that males and heavier users display more risky speed management. Likewise, the heavier cannabis users admitted to increased dangerous driving behaviour, and an accident in the preceding year was associated with a trend towards aggressive driving behaviour according to the DDDI questionnaire. The findings of this study suggest that cannabis users adopt dangerous behaviours when driving, despite the effect this drug has on certain important functions, such as vision. The results suggest a need for awareness-raising and information campaigns.

Effects of cannabis on visual function and self-perceived visual quality

Cannabis is one of the most used drugs of abuse in the world. The objective of this study was to analyze the effects of smoking cannabis on vision and to relate these to those perceived by the user. Thirty-one cannabis users participated in this study. Visual function assessment was carried out in a baseline session as well as after smoking cannabis. We evaluated static visual acuity, contrast sensitivity, stereoacuity, accommodative response, straylight, night-vision disturbances (halos) and pupil size. The participants were also divided into two groups depending on whether they perceived their vision to have worsened after smoking cannabis. A logistic regression analysis was employed to identify which visual test could best predict self-perceived visual effects. The study found that smoking cannabis has significant adverse effects on all the visual parameters analyzed (p < 0.05). Self-perceived visual quality results revealed that about two thirds of the sample think that smoking cannabis impairs their vision. Contrast sensitivity, specifically for the spatial frequency 18 cpd, was identified as the only visual parameter significantly associated with self-perceived visual quality (Odds Ratio: 1.135; p = 0.040). Smoking cannabis is associated with negative effects on visual function. Self-perceived visual quality after smoking cannabis could be related to impaired contrast sensitivity.

Effects of Smoking Cannabis on Visual Function and Driving Performance. A Driving-Simulator Based Study

Cannabis is the most widely used illegal drug in the world. Limited information about the effects of cannabis on visual function is available, and more detail about the possible impact of visual effects on car driving is required. This study investigated the effects of smoking cannabis on vision and driving performance, and whether these effects are correlated. Twenty drivers and occasional users were included (mean (SE) age, 23.3 (1.0) years; five women). Vision and simulated driving performance were evaluated in a baseline session and after smoking cannabis. Under the influence of cannabis, certain visual functions such as visual acuity (p < 0.001), contrast sensitivity (p = 0.004) and stereoacuity (far, p < 0.001; near, p = 0.013) worsened. In addition, there was an overall deterioration of driving performance, with the task of keeping the vehicle in the lane proving more difficult (p < 0.05). A correlation analysis showed significant associations between driving performance and visual function. Thus, the strongest correlations were found between the distance driven onto the shoulder and stereoacuity, for near (ρ = 0.504; p = 0.001) and far distances (ρ = 0.408; p = 0.011). This study provides the first evidence to show that the visual effects of cannabis could impact driving performance, compromising driving safety. The results indicate that information and awareness campaigns are essential for reducing the incidence of driving under the influence of cannabis.

Does cannabis alleviate tinnitus? A review of the current literature

OBJECTIVES

Endocannabinoid pathways have been proposed to affect the underlying pathophysiology of tinnitus. The aim of this study is to evaluate the scope and findings of existing literature on the relationship between cannabis and cannabinoid pathways and tinnitus.

METHODS

We conducted a review of animal, clinical and survey studies investigating the relationship between the use of cannabis-derived agents and tinnitus. Using pertinent keywords and MeSH terms on PubMed, relevant studies were identified, yielding four animal studies, two large cross-sectional survey studies, one clinical cross-over study, and one case report.

RESULTS

Animal studies revealed that cannabinoid receptor expression in the cochlear nucleus varied with tinnitus symptomatology and the use of cannabinoid agents either increased or had no effect on tinnitus-related behavior. Survey studies yielded conflicting results between cannabis use and tinnitus in the general population. Clinical data is largely lacking, although a small cohort study showed a dose-dependent relationship between tetrahydrocannabinol consumption and frequency of tinnitus episodes in patients receiving treatment for cancer.

CONCLUSION

While animal studies have revealed that cannabinoid receptors likely have a role in modulating auditory signaling, there is no compelling data either from animal or human studies for the use of cannabinoids to alleviate tinnitus. Further research is necessary to elucidate their precise role to guide development of therapeutic interventions.

LEVEL OF EVIDENCE

NA.

Short-Term Medical Cannabis Treatment Regimens Produced Beneficial Effects among Palliative Cancer Patients

In the last decade the use of medical cannabis (MC) for palliative cancer treatment has risen. However, the choice between products is arbitrary and most patients are using Tetrahydrocannabinol (THC)-dominant cannabis products. In this study, we aimed to assess the short-term outcomes of MC treatment prescribed by oncologists in relation to the type of cannabis they receive. A comparative analysis was used to assess the differences in treatment effectiveness and safety between THC-dominant (n = 56, 52%), cannabidiol (CBD)-dominant (n = 19, 18%), and mixed (n = 33, 30%) MC treatments. Oncology patients (n = 108) reported on multiple symptoms in baseline questionnaires, initiated MC treatment, and completed a one-month follow-up. Most parameters improved significantly from baseline, including pain intensity, affective and sensory pain, sleep quality and duration, cancer distress, and both physical and psychological symptom burden. There was no significant difference between the three MC treatments in the MC-related safety profile. Generally, there were no differences between the three MC treatments in pain intensity and in most secondary outcomes. Unexpectedly, CBD-dominant oil treatments were similar to THC-dominant treatments in their beneficial effects for most secondary outcomes. THC-dominant treatments showed significant superiority in their beneficial effect only in sleep duration compared to CBD-dominant treatments. This work provides evidence that, though patients usually consume THC-dominant products, caregivers should also consider CBD-dominant products as a useful treatment for cancer-related symptoms.

Cannabis and its constituents for cancer: History, biogenesis, chemistry and pharmacological activities

Cannabis has long been used for healing and recreation in several regions of the world. Over 400 bioactive constituents, including more than 100 phytocannabinoids, have been isolated from this plant. The non-psychoactive cannabidiol (CBD) and the psychoactive Δ⁹-tetrahydrocannabinol (Δ⁹-THC) are the major and widely studied constituents from this plant. Cannabinoids exert their effects through the endocannabinoid system (ECS) that comprises cannabinoid receptors (CB1, CB2), endogenous ligands, and metabolizing enzymes. Several preclinical studies have demonstrated the potential of cannabinoids against leukemia, lymphoma, glioblastoma, and cancers of the breast, colorectum, pancreas, cervix and prostate. Cannabis and its constituents can modulate multiple cancer related pathways such as PKB, AMPK, CAMKK-β, mTOR, PDHK, HIF-1α, and PPAR-γ. Cannabinoids can block cell growth, progression of cell cycle and induce apoptosis selectively in tumour cells. Cannabinoids can also enhance the efficacy of cancer therapeutics. These compounds have been used for the management of anorexia, queasiness, and pain in cancer patients. Cannabinoid based products such as dronabinol, nabilone, nabiximols, and epidyolex are now approved for medical use in cancer patients. Cannabinoids are reported to produce a favourable safety profile. However, psychoactive properties and poor bioavailability limit the use of some cannabinoids. The Academic Institutions across the globe are offering training courses on cannabis. How cannabis and its constituents exert anticancer activities is discussed in this article. We also discuss areas that require attention and more extensive research.

Update on cannabis and cannabinoids for cancer pain

PURPOSE OF REVIEW

The prevalence of cancer pain will continue to rise as pain is common among the survivorship and general cancer population. As interest in cannabis and cannabinoids for medicinal use including pain management continues to rise, there is growing need to update and review the current state of evidence for their use. The literature was searched for articles in English with key words cannabis, cannabinoids, and cancer pain. The sources of articles were PubMed, Embase, and open Google search.

RECENT FINDINGS

In a double-blind randomized placebo-controlled trial including a 3-week treatment period of nabiximol for advanced cancer patients with pain refractory to optimized opiate therapy, improvements in average pain were seen in the intention to treat population (P = 0.0854) and per- protocol population (P = 0.0378).

SUMMARY

To date, preclinical data has demonstrated evidence to suggest promising potential for cancer pain and the urgent need to translate this into clinical practice. Unfortunately, due to limited data, for adults with advanced cancer being treated with opiate therapy, the addition of cannabis or cannabinoids is not currently supported to address cancer pain effectively.

Cannabinoid Hyperemesis Syndrome: A Review of Potential Mechanisms

Introduction: Cannabinoids have long been known for their ability to treat nausea and vomiting. Recent reports, however, have highlighted the paradoxical proemetic effects of cannabinoids. Cannabinoid hyperemesis syndrome (CHS) is characterized by cyclical episodes of nausea and vomiting, accompanied by abdominal pain following prolonged, high-dose cannabis use, which is alleviated by hot baths and showers. Little is known about the cause of this syndrome. Discussion: Cannabinoids produce a biphasic effect on nausea and vomiting, with low doses having an antiemetic effect and high doses producing emesis. Presentation and treatment of CHS are similar to cyclical vomiting syndrome as well as chemotherapy-related anticipatory nausea and vomiting, suggesting that these phenomena may share mechanisms. The prevalence of CHS is not known because of the symptomatic overlap with other disorders and the lack of knowledge of the syndrome by the public and physicians. Treatment with typical antiemetic drugs is ineffective for CHS, but anxiolytic and sedative drugs, along with hot showers, seem to be consistently effective at reducing symptoms. The only known way to permanently end CHS, however, is abstinence from cannabinoids. Case studies and limited pre-clinical data on CHS indicate that prolonged high doses of the main psychotropic compound in cannabis, Δ9-tetrahydrocannabinol (THC), result in changes to the endocannabinoid system by acting on the cannabinoid 1 (CB1) receptor. These endocannabinoid system changes can dysregulate stress and anxiety responses, thermoregulation, the transient receptor potential vanilloid system, and several neurotransmitters systems, and are thus potential candidates for mediating the pathophysiology of CHS. Conclusions: Excessive cannabinoid administration disrupts the normal functioning of the endocannabinoid system, which may cause CHS. More clinical and pre-clinical research is needed to fully understand the underlying pathophysiology of this disorder and the negative consequences of prolonged high-dose cannabis use.

Cannabinoids for adult cancer-related pain: systematic review and meta-analysis

Objectives

There is increased interest in cannabinoids for cancer pain management and legislative changes are in progress in many countries. This study aims to determine the beneficial and adverse effects of cannabis/cannabinoids compared with placebo/other active agents for the treatment of cancer-related pain in adults.

Methods

Systematic review and meta-analysis to identify randomised controlled trials of cannabinoids compared with placebo/other active agents for the treatment of cancer-related pain in adults to determine the effect on pain intensity (primary outcome) and adverse effects, including dropouts. Searches included Embase, MEDLINE, PsycINFO, Web of Science, ClinicalTrials.gov, Cochrane and grey literature. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed.

Results

We identified 2805 unique records, of which six randomised controlled trials were included in this systematic review (n=1460 participants). Five studies were included in the meta-analysis (1442 participants). All had a low risk of bias. There was no difference between cannabinoids and placebo for the difference in the change in average Numeric Rating Scale pain scores (mean difference −0.21 (−0.48 to 0.07, p=0.14)); this remained when only phase III studies were meta-analysed: mean difference −0.02 (−0.21 to 0.16, p=0.80). Cannabinoids had a higher risk of adverse events when compared with placebo, especially somnolence (OR 2.69 (1.54 to 4.71), p<0.001) and dizziness (OR 1.58 (0.99 to 2.51), p=0.05). No treatment-related deaths were reported. Dropouts and mortality rates were high.

Conclusions

Studies with a low risk of bias showed that for adults with advanced cancer, the addition of cannabinoids to opioids did not reduce cancer pain.

Trial registration number

CRD42018107662.

The effects of cannabis, cannabinoids, and their administration routes on pain control efficacy and safety: A systematic review and network meta-analysis

OBJECTIVES

To determine the effects of cannabis, cannabinoids, and their administration routes on pain and adverse euphoria events.

DATA SOURCES

A systematic search was performed in PubMed, ScienceDirect, ClincalTrials.gov, Scopus, Cochrane Library, and Embase from inception until June 2017.

STUDY SELECTION

Randomized controlled trials investigating the effects of cannabis or cannabinoids on pain reduction.

DATA EXTRACTION

Two reviewers extracted and assessed the quality of studies by means of Cochrane risk of bias. Standardized mean difference (SMD) was calculated. Random-effects model was undertaken to pool the treatment effects.

RESULTS

A total of 25 studies involving 2270 patients were included. We found that delta-9-tetrahydrocannabinol/cannabidiol (THC/CBD) (oromucosal route), THC (oromucosal route), and standardized dried cannabis (with THC; SCT; inhalation route) could reduce neuropathic pain score (SMD -0.41, 95% CI -0.7 to -0.1; -0.61, 95% CI -1.2 to -0.02; and -0.77, 95% CI -1.4 to -0.2; respectively). For nociceptive pain, only standardized cannabis extract (with THC; SCET) via oral route could reduce pain score (SMD -1.8, 95% C; -2.4 to -1.2). In cancer pain, THC/CBD via oromucosal route and THC via oral or oromucosal route could reduce pain score (SMD -0.7, 95% CI -1.2 to -0.2; and -2.1, 95% CI -2.8 to -1.4; respectively). No study was observed for THC/CBD via oral route or inhalation or THC via inhalation for cancer and nociceptive pain, SCET via oromucosal route or inhalation for neuropathic and cancer pain, THC via oromucosal route for nociceptive pain, and SCT via oromucosal or oral route for neuropathic, cancer, and nociceptive pain. Statistically significant increased risks of euphoria were observed in THC/CBD (oromucosal), THC (oromucosal), and SCT (inhalation).

CONCLUSION

The use of cannabis and cannabinoids via certain administration routes could reduce different types of pain. Product developers could consider our findings as part of their product design so that the effective route of cannabis and cannabinoids for pain control can be achieved.

Opioid use and misuse: health impact, prevalence, correlates and interventions

Objective: To provide a broad overview of the state of drug misuse research, particularly focusing on opioid drug use in the U.S.A. Design: An overview of published reviews of the literature. Results: Prescription opioid use has increased globally from 2008 to 2013, while use of opiates such as heroin and opium have remained stable in many countries, although, decreases have been observed in parts of Europe. Opioid misuse is highest in the United States; approximately 11.8 million Americans misused opioids in 2016. Demographic, genetic, psychosocial and structural/environmental factors all play a role in determining who will become an opioid misuser. Strategies such as increased prescribing of non-opioid derived pain relievers, expansion of medication treatment, distribution of naloxone for overdose reversal and supervised consumption sites are some of the solutions posed to reduce the spread and consequences of opioid misuse. Conclusion: Research focused on understanding of opioid neurobiology, as well as empirically based, effective alternatives to pain management and implementation studies on combined prevention and treatment approaches are needed. It will take the combined effort of community members, healthcare professionals, policymakers and researchers in order to prevent and treat opioid misuse.