Efficacy Of Medical Cannabis Research Articles

Medical cannabis for children: Evidence and recommendations.

Interest in using cannabis products for a medical purpose in children under the age of 18 years is increasing. There are many medical cannabis products available that can include cannabidiol (CBD) or delta-9-tetrahydrocannabinol (THC), or both. Despite many therapeutic claims, there are few rigorous studies to inform the dosing, safety, and efficacy of medical cannabis in paediatric clinical practice. This statement reviews the current evidence and provides recommendations for using medical cannabis in children. Longer-term (2-year) reports support the sustained tolerability and efficacy of cannabidiol therapy for patients with Lennox-Gastaut and Dravet syndromes. CBD-enriched cannabis extracts containing small amounts of THC have been evaluated in a small number of paediatric patients, and further research is needed to inform clinical practice guidelines. Given the widespread use of medical cannabis in Canada, paediatricians should be prepared to engage in open, ongoing discussions with families about its potential benefits and risks, and develop individualized plans that monitor efficacy, reduce harms, and mitigate drug-drug interactions.

Is Cannabis Effective in the Treatment of Chronic Back Pain?

Cannabis is commonly recognized as a recreational substance. It has been explored for its potential therapeutic applications in addressing various conditions, such as depression, anxiety, sleep disorders, neurological disorders, and chronic low back pain, which affect a significant portion of the population. In the United Kingdom, cannabis has been recognized and licensed for medical use since November 2018, with about 12 National Health Service prescriptions in circulation largely due to patient pressure, with support from media campaigns for its use when there was growing evidence of its use in intractable epilepsy. Cannabis is beginning to gain traction as an alternative or even a complementary drug to opiates with some pre-clinical studies showing opiate-sparing effects. Despite references to its therapeutic use, cannabis as a therapeutic drug has been controversial due to the negative perception of its use as a recreational drug. As a result, there have been challenges in changing the perception of healthcare authorities and clinicians on the use of cannabis as a therapeutic tool for pain relief. The stigma associated with cannabis could be responsible for the paucity of randomized controlled trials on the efficacy of medical cannabis, further decreasing the credibility of the few trials conducted.

Concerns, beliefs and attitudes of pharmacists and pharmacy students on cannabis use in Canada.

Since cannabis has been legalized in Canada for medical and recreational use, there has been an increased demand on pharmacists for cannabis counselling. The objective of this study was to determine the concerns, beliefs and attitudes of Canadian pharmacists and pharmacy students towards using cannabis. An online survey was synthesized under 3 broad themes: concerns, beliefs and attitudes about cannabis, consisting of 27 questions capturing demographics and Likert scale responding to survey questions. We examined whether there were differences in responses by geographic location (i.e., Ontario, Quebec, Canada), sex or practice setting (i.e., community, hospital). Across Canada, there were 654 survey respondents, with 399 in Ontario and 95 in Quebec. Approximately 24% indicated they had used cannabis since legalization, 69% indicated they believed cannabis should be available for medical and recreational use and 34% indicated their perceptions towards cannabis had become more positive since legalization. Relative to Quebec or the rest of Canada, respondents from Ontario were significantly more likely to be comfortable providing counselling to and answering questions of patients on the safety and efficacy of medical cannabis use. Examining sex differences across Canada, male respondents were more comfortable than female counselling patients on the safety and efficacy of medical cannabis. The current results reinforce the perceived need by pharmacists and pharmacy students for targeted education, and future research in cannabis education should consider potential gender differences in attitudes and beliefs surrounding cannabis therapy.

Safety and Efficacy of Medical Cannabis in Autism Spectrum Disorder Compared with Commonly Used Medications.

Objective: The objective of this study was to evaluate the safety and efficacy of medications commonly used in autism spectrum disorder (ASD) and compare this to what current research has shown regarding medical cannabis use in this population. Methods: Searches were performed to collect information surrounding currently used medications and their safety and efficacy profiles, biologic plausibility of cannabis use for symptoms of ASD, and studies detailing cannabis' safety and efficacy profile for use in the ASD population. Results were used to compare medications to cannabis as a proposed treatment. Results: The heterogeneity of ASD produces great difficulties in finding appropriate treatment, leading to many medication changes or treatment trials throughout a patient's life. Commonly prescribed medications display varying levels of efficacy, safety, and tolerability between patients and symptoms targeted. Some of the most common side effects cited are also considered the most troubling symptoms associated with ASD; aggression, anxiety, irritability, and a negative effect on cognition, leading many patients to discontinue use as the side effects outweigh benefits. Recent case reports and retrospective studies have displayed the potential efficacy, safety, and tolerability of cannabidiol (CBD)-rich medical cannabis use for treating both core symptoms of ASD and many comorbid symptoms such as irritability and sleep problems. Studies have also identified circulating endocannabinoids as a possible biomarker for ASD, providing another possible method of diagnosis. Conclusions: Currently, there are no approved medications for the core symptoms of ASD and only two medications Food and Drug Administration approved for associated irritability. Prescribed medications for symptoms associated with ASD display varying levels of efficacy, safety, and tolerability among the heterogeneous ASD population. At the time of this study there are no published placebo-controlled trials of medical cannabis for ASD and the observational studies have limitations. CBD-rich medical cannabis seems to be an effective, tolerable, and relatively safe option for many symptoms associated with ASD, however, the long-term safety is unknown at this time.

Use and caregiver-reported efficacy of medical cannabis in children and adolescents in Switzerland

Evidence on the use and efficacy of medical cannabis for children is limited. We examined clinical and epidemiological characteristics of medical cannabis treatment and caregiver-reported effects in children and adolescents in Switzerland. We collected clinical data from children and adolescents (< 18 years) who received Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), or a combination of the two between 2008 and 2019 in Switzerland. Out of 205 contacted families, 90 agreed to participate. The median age at the first prescription was 11.5 years (interquartile range (IQR) 6–16), and 32 patients were female (36%). Fifty-one (57%) patients received CBD only and 39 (43%) THC. Patients were more likely to receive THC therapy if one of the following symptoms or signs were present: spasticity, pain, lack of weight gain, vomiting, or nausea, whereas seizures were the dominant indication for CBD therapy. Improvements were reported in 59 (66%) study participants. The largest treatment effects were reported for pain, spasticity, and frequency of seizures in participants treated with THC, and for those treated with pure CBD, the frequency of seizures. However, 43% of caregivers reported treatment interruptions, mainly because of lack of improvement (56%), side effects (46%), the need for a gastric tube (44%), and cost considerations (23%).Conclusions: The effects of medical cannabis in children and adolescents with chronic conditions are unknown except for rare seizure disorders, but the caregiver-reported data analysed here may justify trials of medical cannabis with standardized concentrations of THC or CBD to assess its efficacy in the young.What is Known:• The use of medical cannabis (THC and CBD) to treat a variety of diseases among children and adolescents is increasing.• In contrast to adults, there is no evidence to support the use of medical cannabis to treat chronic pain and spasticity in children, but substantial evidence to support the use of CBD in children with rare seizure disorders.What is New:• This study provides important insights into prescription practices, dosages, and treatment outcomes in children and adolescents using medical cannabis data from a real-life setting.• The effects of medical cannabis in children and adolescents with chronic conditions shown in our study support trials of medical cannabis for chronic conditions.

Developing a real-world evidence base for prescribed cannabis in the United Kingdom: preliminary findings from Project Twenty21.

The therapeutic potential of medical cannabis to treat a variety of conditions is becoming increasingly recognised. Globally, a large number of countries have now legalised cannabis for medical uses and a substantial number of patients are able to access their medications. Yet in the UK, where medical cannabis was legalised in November 2018, only a handful of NHS prescriptions have been written, meaning that most patients are unable to access the medicine. Reasons for this are manyfold and include the perceived lack of clinical evidence due to the challenges of studying medical cannabis through randomised controlled trials. In order to develop the current evidence base, the importance of incorporating real-world data (RWD) to assess the effectiveness and efficacy of medical cannabis has gradually become recognised. The current paper provides a detailed outline of Project Twenty21 (T21), the UK's first medical cannabis registry, launched in August 2020. We provide the rationale for T21 and describe the methodology before reporting the characteristics of the 'first patients' enrolled in the registry. We describe the health status of all patients enrolled into the project during its first 7months of operation and the sociodemographic characteristics and primary presenting conditions for these patients, as well as details of the medical cannabis prescribed to these individuals. By 12th March 2021, 678 people had been enrolled into T21; the majority (64%) were male and their average age was 38.7years (range = 18-80). The most commonly reported primary conditions were chronic pain (55.6%) and anxiety disorders (32.0%) and they reported high levels of multi-morbidity, including high rates of insomnia and depression. We also present preliminary evidence from 75 patients followed up after 3months indicating that receipt of legal, prescribed cannabis was associated with a significant increase in self-reported health, assessed using the visual analogue scale of the EQ-5D-5L (Cohen's d = .77, 95% CI = .51-1.03). Our initial findings complement reports from other large-scale databases globally, indicating that the current RWD is building up a pattern of evidence. With many clinicians demanding better and faster evidence to inform their decisions around prescribing medical cannabis, the current and future results of T21 will expand the existing evidence base on the effectiveness of cannabis-based medical products (CBMPs).

Cross national comparison of medical students’ attitudes and beliefs about medical cannabis and its application for pain management

ObjectivesTo examine attitudes and beliefs about medical cannabis (MC), and specifically about its application for pain management, across medical students in Israel and Thailand. DesignCross-sectional survey which measured attitudes and beliefs about MC. Participants were additionally asked to rate the perceived efficacy of MC for different medical conditions that are related to pain (arthritis, chronic pain, fibromyalgia and multiple sclerosis). Pearson's Chi-squared test was used to compare between students from the participating universities. Results430 medical students participated, 37.9 % (n = 163) from Israel and 62.1 % (n = 267) from Thailand. Personal cannabis use was reported by 55.6 % of the Israeli and only by 6.9 % of the Thai students (p < .001). Israeli secular students, compared to those from Thailand, were more likely to recommend MC for patient treatment, less concerned about serious physical and mental health risks, and more inclined to support legalization of recreational cannabis. Israeli students reported more permissive attitudes toward MC, but reported feeling less prepared to answer patient/client questions about MC than their Thai counterparts. ConclusionsThe findings of this study accentuate the need for curriculum designed around MC use to promote students' preparedness to serve patients in pain or with other medical conditions that may benefit from MC use.

Gastroenterologists’ Attitude Regarding Medical Cannabis for Inflammatory Bowel Diseases in Israel

Background: The use of medical cannabis (MC) for inflammatory bowel diseases (IBDs) is expanding. Current evidence does not support the efficacy of MC for reducing inflammation in IBD patients. Even so, many gastroenterologists encounter the issue of recommending use of MC to IBD patients. Methods: A Web-based survey was completed by 84 (34%) gastroenterologists in Israel. Results: Out of 84 physicians whom completed the questionnaire, 59 (70%) were male, 34 (40%) were under age 50 years, 71 (85%) were adult gastroenterologists, and 53 (63%) work mainly in a hospital. Of them, 15, 41, and 44% of physicians think that MC is very effective, mildly effective, and not effective at all, respectively. Physicians will commonly, rarely, and never recommend MC in 31, 47, and 22%, respectively. Older physicians (above age 50 years) were significantly more likely to have a positive attitude towards MC in both questions. When presented with a clinical scenario of a patient in deep remission, requesting to increase the dose, 32% would increase, 49% would maintain, and only 18% would stop prescribing MC altogether; 48% of physicians did not know the recommended initial dose for MC. Only 2 (2.5%) physicians initiated the use of MC to all patients. Female gastroenterologists were significantly more likely to initiate MC, p = 0.048. Conclusion: The use of MC for IBD patients is commonly encountered. Completely different attitudes regarding this treatment were seen. Age above 50 years and female physicians generally had a more positive attitude towards the use of MC. Guidelines and clear recommendations are needed.

Safety and efficacy of low-dose medical cannabis oils in multiple sclerosis

The use of cannabis as medical therapy to treat chronic pain and spasticity in patients with multiple sclerosis (MS) is increasing. However, the evidence on safety when initiating treatment with medical cannabis oils is limited. The aim of this study was to investigate the safety of sublingual medical cannabis oils in patients with MS. In this prospective observational safety study 28 patients with MS were treated with medical cannabis oils (THC-rich, CBD-rich and THC+CBD combined products) and were followed during a titration period of four weeks. Patients were evaluated at treatment start (Visit 1) and after four weeks treatment (Visit 2). At each visit neurological examination (Expanded Disability Status Scale - EDSS), ambulation (Timed 25-Foot Walk Test - T25FWT), routine blood tests, plasma cannabinoids, dexterity (9-Hole Peg Test - 9-HPT) and processing speed (Symbol Digit Modalities Test - SDMT) were tested. Adverse events (AEs) and tolerability were reported at Visit 2. Secondary, efficacy of medical cannabis on pain, spasticity and sleep disturbances were measured by numeric rating scale (NRS-11) each day during the 4-week treatment period. During treatment with cannabis preparations containing 10-25 mg/mL THC, the most common AEs were dry mouth, drowsiness, dizziness and nausea of mild to moderate degree. Two patients experienced pronounced symptoms with excessive dreaming and drowsiness, respectively, which led to treatment stop during the titration. Three serious adverse events (SAE) were reported but were not associated with the treatment. Mean doses of THC and CBD were 4.0 mg and 7.0 mg, respectively, and primarily administered as a once-daily evening dose. Furthermore, pain decreased from a median NRS score of 7 to 4, (p=0.01), spasticity decreased from a median NRS score of 6 to 2.5 (p=0.01) and sleep disturbances decreased from a median NRS score of 7 to 3 (p < 0.001). No impairment in disability, ambulation, dexterity or processing speed was observed. Treatment with medical cannabis oils was safe and well tolerated, and resulted in a reduction in pain intensity, spasticity and sleep disturbances in MS patients. This suggests that medical cannabis oils can be used safely, especially at relatively low doses and with slow titration, as an alternative to treat MS-related symptoms when conventional therapy is inadequate.

Medical cannabis treatment for chronic pain: Outcomes and prediction of response.

Although studied in a few randomized controlled trials, the efficacy of medical cannabis (MC) for chronic pain remains controversial. Using an alternative approach, this multicentre, questionnaire-based prospective cohort was aimed to assess the long-term effects of MC on chronic pain of various aetiologies and to identify predictors for MC treatment success. Patients with chronic pain, licensed to use MC in Israel, reported weekly average pain intensity (primary outcome) and related symptoms before and at 1, 3, 6, 9 and 12months following MC treatment initiation. A general linear model was used to assess outcomes and identify predictors for treatment success (≥30% reduction in pain intensity). A total of 1,045 patients completed the baseline questionnaires and initiated MC treatment, and 551 completed the 12-month follow-up. At 1year, average pain intensity declined from baseline by 20% [-1.97 points (95%CI= -2.13 to -1.81; p<0.001)]. All other parameters improved by 10%-30% (p<0.001). A significant decrease of 42% [reduction of 27mg; (95%CI=-34.89 to18.56, p<0.001)] from baseline in morphine equivalent daily dosage of opioids was also observed. Reported adverse effects were common but mostly non-serious. Presence of normal to long sleep duration, lower body mass index and lower depression score predicted relatively higher treatment success, whereas presence of neuropathic pain predicted the opposite. This prospective study provides further evidence for the effects of MC on chronic pain and related symptoms, demonstrating an overall mild-to-modest long-term improvement of the tested measures and identifying possible predictors for treatment success.

Trends in medical cannabis licensure, Israel, 2013-2018.

Since 2011, the Israeli Ministry of Health has been working towards increased regulation of its medical cannabis (MC) program by ensuring that MC licensing procedures adhere to the basic principles and practices of the medical profession. The aim of this study is to examine trends in MC licensing in Israel during this period of increasing MC regulation. Publicly available data on MC licences, collected by the Ministry of Health, were used to examine trends between 2013 and 2018. The number of MC licences, new MC licence requests and rate of MC licence requests accepted were plotted over time. Gender and age distributions and the medical indicators for which MC licences were approved were also examined. Absolute numbers of MC licences and MC licence requests increased during the study period while no parallel increase in the rate at which new MC licences were granted was observed. MC licences for post-traumatic stress disorder increased substantially during the study period. The majority of MC patients in Israel are male, over the age of 40, and used MC for chronic pain. The observed increase in MC licences is likely driven by an increase in patient demand. This study suggests that social forces (e.g. positive media reporting and public attitudes towards MC), beyond MC regulation, are influencing trends in MC licensing in Israel. Studies that examine the skewed gender distribution of MC licences, and the efficacy of MC for post-traumatic stress disorder, are urgently needed.

Medical Cannabis in Children.

The use of medical cannabis in children is rapidly growing. While robust evidence currently exists only for pure cannabidiol (CBD) to treat specific types of refractory epilepsy, in most cases, artisanal strains of CBD-rich medical cannabis are being used to treat children with various types of refractory epilepsy or irritability associated with autism spectrum disorder (ASD). Other common pediatric disorders that are being considered for cannabis treatment are Tourette syndrome and spasticity. As recreational cannabis use during youth is associated with serious adverse events and medical cannabis use is believed to have a relatively high placebo effect, decisions to use medical cannabis during childhood and adolescence should be made with caution and based on evidence. This review summarizes the current evidence for safety, tolerability, and efficacy of medical cannabis in children with epilepsy and in children with ASD. The main risks associated with use of Δ9-tetrahydrocannabinol (THC) and CBD in the pediatric population are described, as well as the debate regarding the use of whole-plant extract to retain a possible “entourage effect” as opposed to pure cannabinoids that are more standardized and reproducible.

Insufficient evidence for cannabinoids in the treatment of mental disorders

The most comprehensive review to date of medicinal cannabinoids for the treatment of mental disorders has concluded that the evidence is insufficient to justify their use. A greater number of high‐quality trials is necessary to assess the safety and efficacy of medical cannabis and derivatives such as the increasingly popular cannabidiol (CBD), authors of the review and meta‐analysis stated. Results were published online Oct. 28 in Lancet Psychiatry.

Safety and Efficacy of Medical Cannabis in Fibromyalgia.

Background: Chronic pain may be treated by medical cannabis. Yet, there is scarce evidence to support the role of medical cannabis in the treatment of fibromyalgia. The aim of the study was to investigate the characteristics, safety, and effectiveness of medical cannabis therapy for fibromyalgia. Methods: A prospective observational study with six months follow-up period based on fibromyalgia patients who were willing to answer questionnaire in a specialized medical cannabis clinic between 2015 and 2017. Results: Among the 367 fibromyalgia patients, the mean age was 52.9 ± 15.1, of whom 301 (82.0%) were women. Twenty eight patients (7.6%) stopped the treatment prior to the six months follow-up. The six months response rate was 70.8%. Pain intensity (scale 0–10) reduced from a median of 9.0 at baseline to 5.0 (p < 0.001), and 194 patients (81.1%) achieved treatment response. In a multivariate analysis, age above 60 years (odds ratio [OR] 0.34, 95% C.I 0.16–0.72), concerns about cannabis treatment (OR 0.36, 95% C.I 0.16–0.80), spasticity (OR 2.26, 95% C.I 1.08–4.72), and previous use of cannabis (OR 2.46 95% C.I 1.06–5.74) were associated with treatment outcome. The most common adverse effects were mild and included dizziness (7.9%), dry mouth (6.7%), and gastrointestinal symptoms (5.4%). Conclusion: Medical cannabis appears to be a safe and effective alternative for the treatment of fibromyalgia symptoms. Standardization of treatment compounds and regimens are required.

Medical Cannabis: Effects on Opioid and Benzodiazepine Requirements for Pain Control.

Background: There is currently little evidence regarding the use of medical cannabis for the treatment of intractable pain. Literature published on the subject to date has yielded mixed results concerning the efficacy of medical cannabis and has been limited by study design and regulatory issues. Objective: The objective of this study was to determine if the use of medical cannabis affects the amount of opioids and benzodiazepines used by patients on a daily basis. Methods: This single-center, retrospective cohort study evaluated opioid and benzodiazepine doses over a 6-month time period for patients certified to use medical cannabis for intractable pain. All available daily milligram morphine equivalents (MMEs) and daily diazepam equivalents (DEs) were calculated at baseline and at 3 and 6 months. Results: A total of 77 patients were included in the final analysis. There was a statistically significant decrease in median MME from baseline to 3 months (-32.5 mg; P = 0.013) and 6 months (-39.1 mg; P = 0.001). Additionally, there was a non-statistically significant decrease in median DE at 3 months (-3.75 mg; P = 0.285) and no change in median DE from baseline to 6 months (-0 mg; P = 0.833). Conclusion and Relevance: Over the course of this 6-month retrospective study, patients using medical cannabis for intractable pain experienced a significant reduction in the number of MMEs available to use for pain control. No significant difference was noted in DE from baseline. Further prospective studies are warranted to confirm or deny the opioid-sparing effects of medical cannabis when used to treat intractable pain.

Safety and Efficacy of Medical Cannabis in Elderly Patients: A Retrospective Review in a Neurological Outpatient Setting. (P4.1-014)

Safety and Efficacy of Medical Cannabis in Elderly Patients: A Retrospective Review in a Neurological Outpatient Setting. (P4.1-014)

Epidemiological characteristics, safety and efficacy of medical cannabis in the elderly

IntroductionThere is a substantial growth in the use of medical cannabis in recent years and with the aging of the population, medical cannabis is increasingly used by the elderly. We aimed to assess the characteristics of elderly people using medical cannabis and to evaluate the safety and efficacy of the treatment. MethodsA prospective study that included all patients above 65 years of age who received medical cannabis from January 2015 to October 2017 in a specialized medical cannabis clinic and were willing to answer the initial questionnaire. Outcomes were pain intensity, quality of life and adverse events at six months. ResultsDuring the study period, 2736 patients above 65 years of age began cannabis treatment and answered the initial questionnaire. The mean age was 74.5 ± 7.5 years. The most common indications for cannabis treatment were pain (66.6%) and cancer (60.8%). After six months of treatment, 93.7% of the respondents reported improvement in their condition and the reported pain level was reduced from a median of 8 on a scale of 0–10 to a median of 4. Most common adverse events were: dizziness (9.7%) and dry mouth (7.1%). After six months, 18.1% stopped using opioid analgesics or reduced their dose. ConclusionOur study finds that the therapeutic use of cannabis is safe and efficacious in the elderly population. Cannabis use may decrease the use of other prescription medicines, including opioids. Gathering more evidence-based data, including data from double-blind randomized-controlled trials, in this special population is imperative.

Prospective analysis of safety and efficacy of medical cannabis in large unselected population of patients with cancer

BackgroundCancer is a major public health problem as the leading cause of death. Palliative treatment aimed to alleviate pain and nausea in patients with advanced disease is a cornerstone of oncology. In 2007, the Israeli Ministry of Health began providing approvals for medical cannabis for the palliation of cancer symptoms. The aim of this study is to characterize the epidemiology of cancer patients receiving medical cannabis treatment and describe the safety and efficacy of this therapy. MethodsWe analyzed the data routinely collected as part of the treatment program of 2970 cancer patients treated with medical cannabis between 2015 and 2017. ResultsThe average age was 59.5 ± 16.3 years, 54.6% women and 26.7% of the patients reported previous experience with cannabis. The most frequent types of cancer were: breast (20.7%), lung (13.6%), pancreatic (8.1%) and colorectal (7.9%) with 51.2% being at stage 4. The main symptoms requiring therapy were: sleep problems (78.4%), pain (77.7%, median intensity 8/10), weakness (72.7%), nausea (64.6%) and lack of appetite (48.9%). After six months of follow up, 902 patients (24.9%) died and 682 (18.8%) stopped the treatment. Of the remaining, 1211 (60.6%) responded; 95.9% reported an improvement in their condition, 45 patients (3.7%) reported no change and four patients (0.3%) reported deterioration in their medical condition. ConclusionsCannabis as a palliative treatment for cancer patients seems to be well tolerated, effective and safe option to help patients cope with the malignancy related symptoms.

Medical Cannabis and Chronic Opioid Therapy

ABSTRACTFourteen states and the District of Columbia have legalized the use of cannabis for medical purposes. A small, high-quality literature supports the efficacy of medical cannabis for the treatment of neuropathic pain. The smoked botanical product, however, is associated with a number of adverse medical and psychiatric consequences. Furthermore, experimental data indicate that acute use of cannabis results in impairment of every important metric related to the safe operation of a motor vehicle. Epidemiological data show associations between recent cannabis use and both psychomotor impairment and motor vehicle crashes, associations that are strengthened by the concomitant use of alcohol and other central nervous system depressants. Finally, data from pain clinics reveals an unusually high prevalence of cannabis use in nearly all age groups and an association between cannabis use and opioid and other substance misuse. Based on available data and expert opinion, concomitant use of cannabis and opioids is an absolute contraindication to the operation of a motor vehicle. In patients who use cannabis and are prescribed opioids, heightened vigilance for opioid- and other substance-related problems is warranted. It is appropriate to refrain from prescribing opioids to individuals using medical cannabis if there is reasonable suspicion that the combination will pose a risk to the patient or others.