Therapeutic use ofCannabis sativaon chemotherapy-induced nausea and vomiting among cancer patients: systematic review and meta-analysis

Orthopaedic surgery patients who use recreational marijuana have less pre-operative pain

AIMS

To determine the baseline clinical characteristics of recreational marijuana users undergoing outpatient orthopaedic surgery. We hypothesized that patients who report marijuana use would have worse pain, function, and general health status.

PATIENTS AND METHODS

Nine-hundred and thirty-seven patients undergoing outpatient orthopaedic surgery were asked to fill out patient-reported outcome (PRO) tools. These PROs included the Patient-Reported Outcomes Measurement Information Systems (PROMIS) computer adaptive tests and legacy PROs unique to each patients' surgical site.

RESULTS

Forty patients (4.2%) reported marijuana use. Marijuana use was associated with younger age (33 vs. 43 years, p < 0.001), having a history of fewer operations (1.8 vs. 3.2, p < 0.05), single marital status (68 vs. 38%, p < 0.01), and having a history of smoking cigarettes (63 vs. 31%, p < 0.0001). Marijuana use was found to be significantly associated with greater Marx lower extremity activity rating scale scores (8.5 points vs. 6.1 points, p < 0.05) and decreased pain intensity in the operative site (3.7 points vs. 5.0 points, p < 0.05). Multivariable analysis found that marijuana use was an independent factor associated with less pain intensity in the operative site (p < 0.05).

CONCLUSION

Our studies support other national studies that report increased marijuana use among younger patients and those who smoke cigarettes. The results do not support our hypothesis, as marijuana use was associated with less pain and better lower extremity activity rating scale scores when compared to non-users. Further research is warranted to analyze the effects of marijuana use on orthopaedic surgery patients.

STUDY DESIGN

Cross-sectional study.

Perceptions of the cognitive effects of cannabis use: A survey of neuropsychologists' beliefs

Introduction: Research evaluating the neuropsychological effects of cannabis has yielded mixed findings, with some studies finding cognitive deficits in cannabis users (primarily in learning and memory) and others finding no significant effects. It is important to understand how clinicians perceive this discrepancy in the empirical literature. However, no studies have assessed neuropsychologists' beliefs regarding the effects of cannabis on cognitive functioning. Thus, this study sought to evaluate how patient and cannabis-use factors influence neuropsychologists' perceptions of cannabis's cognitive effects. Method: Neuropsychologists (N = 261) read eight vignettes, each depicting cannabis users varying in age, gender, and cannabis-use history (frequency, duration, and recreational/medicinal use). Respondents rated the anticipated effects of cannabis in each vignette on nine cognitive domains. Mixed effects linear regression modeled the ratings of cognitive abilities as a function of neuropsychologist, neuropsychologists' training, vignette, patient age, gender, and frequency/duration/type of cannabis use, and treated neuropsychologist and vignette as random effects. Results: Duration of use had the most notable effect on neuropsychologists' ratings, with a small (0.1 to 0.2 SDs) yet statistically significant (p < .001) negative effect on each cognitive domain. Male gender and medicinal use also predicted lower cognitive ratings. Differences in ratings between neuropsychologists accounted for 73% of the total variability in each domain, whereas variability due to vignette alone was negligible (<1%). Conclusions: Results suggest that neuropsychologists believe that cannabis use results in broad but mild cognitive deficits, consistent with meta-analytic findings of active chronic cannabis users, particularly for males and for individuals using cannabis for medicinal purposes. Interestingly, neuropsychologists expected fewer cognitive effects in recreational cannabis users. Further, duration of use (rather than frequency) was believed to be the primary factor contributing to cognitive deficits.

Cannabinoid pharmacology and therapy in gut disorders

Cannabis sp. and their products (marijuana, hashish…), in addition to their recreational, industrial and other uses, have a long history for their use as a remedy for symptoms related with gastrointestinal diseases. After many reports suggesting these beneficial effects, it was not surprising to discover that the gastrointestinal tract expresses endogenous cannabinoids, their receptors, and enzymes for their synthesis and degradation, comprising the so-called endocannabinoid system. This system participates in the control of tissue homeostasis and important intestinal functions like motor and sensory activity, nausea, emesis, the maintenance of the epithelial barrier integrity, and the correct cellular microenvironment. Thus, different cannabinoid-related pharmacological agents may be useful to treat the main digestive pathologies. To name a few examples, in irritable bowel syndrome they may normalize dysmotility and reduce pain, in inflammatory bowel disease they may decrease inflammation, and in colorectal cancer, apart from alleviating some symptoms, they may play a role in the regulation of the cell niche. This review summarizes the main recent findings on the role of cannabinoid receptors, their synthetic or natural ligands and their metabolizing enzymes in normal gastrointestinal function and in disorders including irritable bowel syndrome, inflammatory bowel disease, colon cancer and gastrointestinal chemotherapy-induced adverse effects (nausea/vomiting, constipation, diarrhea).

Therapeutic Cannabis and Endocannabinoid Signaling System Modulator Use in Otolaryngology Patients

Objectives

1) review benefits and risks of cannabis use, with emphasis on otolaryngic disease processes; 2) define and review the endocannabinoid signaling system (ESS); and 3) review state and federal regulations for the use and research of cannabis and ESS modulators.

Methods

This manuscript is a review of the current literature relevant to the stated objectives.

Results

Cannabis (marijuana) use is increasing. It is the most widely used illicit substance in the world. There is increasing interest in its therapeutic potential due to changing perceptions, new research, and legislation changes controlling its use. The legal classification of cannabis is complicated due to varied and conflicting state and federal laws. There are currently two synthetic cannabinoid drugs that are FDA approved. Current indications for use include chemotherapy‐related nausea and vomiting, cachexia, and appetite loss. Research has demonstrated potential benefit for use in many other pathologies including pain, inflammatory states, and malignancy. Data exists demonstrating potential antineoplastic benefit in oral, thyroid, and skin cancers.

Conclusions

ESS modulators may play both a causal and therapeutic role in several disorders seen in otolaryngology patients. The use of cannabis and cannabinoids is not without risk. There is a need for further research to better understand both the adverse and therapeutic effects of cannabis use. With increasing rates of consumption, elevated public awareness, and rapidly changing legislation, it is helpful for the otolaryngologist to be aware of both the adverse manifestations of use and the potential therapeutic benefits when talking with patients.

Secondary metabolite production by cereal-associated penicillia during cultivation on cereal grains

Cereals are vulnerable substrates for fungal growth and subsequent mycotoxin contamination. One of the major fungal genera to colonize the ecosystem of stored grain is Penicillium, especially species in the series of Viridicata and Verrucosa. Culturing these species on grains, we hoped to induce the production of relevant secondary metabolites produced by these fungi in the early stage of cereal breakdown. In a multivariate setup six different cereal grains (wheat, rye, barley, oat, rice, and maize), one kind of white beans, and two standard fungal media, Yeast Extract Sucrose agar (YES agar) and Czapek Yeast Autolysate agar (CYA agar), were inoculated with the ten most important cereal-associated species from Penicillium (P. aurantiogriseum, P. cyclopium, P. freii, P. melanoconidium, P. neoechinulatum, P. polonicum, P. tricolor, P. viridicatum, P. hordei, and P. verrucosum). P. nordicum is a meat-associated species, which was included due to its chemical association with P. verrucosum, in addition to see if a substrate change would alter the profile of known chemistry. We found that cereals function very well as substrates for secondary metabolite production, but did not present significantly different secondary metabolite profiles, concerning known chemistry, as compared to standard laboratory agar media. However, white beans altered the semi-quantitative secondary metabolite profiles for several species. Correlations between substrates and certain metabolites were observed, as illuminated by principal component analysis. Many bioactive secondary metabolites were observed for the first time in the analyzed fungal species, including ergot type alkaloids in P. hordei.

Patterns of medicinal cannabis use, strain analysis, and substitution effect among patients with migraine, headache, arthritis, and chronic pain in a medicinal cannabis cohort

BACKGROUND

Medicinal cannabis registries typically report pain as the most common reason for use. It would be clinically useful to identify patterns of cannabis treatment in migraine and headache, as compared to arthritis and chronic pain, and to analyze preferred cannabis strains, biochemical profiles, and prescription medication substitutions with cannabis.

METHODS

Via electronic survey in medicinal cannabis patients with headache, arthritis, and chronic pain, demographics and patterns of cannabis use including methods, frequency, quantity, preferred strains, cannabinoid and terpene profiles, and prescription substitutions were recorded. Cannabis use for migraine among headache patients was assessed via the ID Migraine™ questionnaire, a validated screen used to predict the probability of migraine.

RESULTS

Of 2032 patients, 21 illnesses were treated with cannabis. Pain syndromes accounted for 42.4% (n = 861) overall; chronic pain 29.4% (n = 598;), arthritis 9.3% (n = 188), and headache 3.7% (n = 75;). Across all 21 illnesses, headache was a symptom treated with cannabis in 24.9% (n = 505). These patients were given the ID Migraine™ questionnaire, with 68% (n = 343) giving 3 "Yes" responses, 20% (n = 102) giving 2 "Yes" responses (97% and 93% probability of migraine, respectively). Therefore, 88% (n = 445) of headache patients were treating probable migraine with cannabis. Hybrid strains were most preferred across all pain subtypes, with "OG Shark" the most preferred strain in the ID Migraine™ and headache groups. Many pain patients substituted prescription medications with cannabis (41.2-59.5%), most commonly opiates/opioids (40.5-72.8%). Prescription substitution in headache patients included opiates/opioids (43.4%), anti-depressant/anti-anxiety (39%), NSAIDs (21%), triptans (8.1%), anti-convulsants (7.7%), muscle relaxers (7%), ergots (0.4%).

CONCLUSIONS

Chronic pain was the most common reason for cannabis use, consistent with most registries. The majority of headache patients treating with cannabis were positive for migraine. Hybrid strains were preferred in ID Migraine™, headache, and most pain groups, with "OG Shark", a high THC (Δ9-tetrahydrocannabinol)/THCA (tetrahydrocannabinolic acid), low CBD (cannabidiol)/CBDA (cannabidiolic acid), strain with predominant terpenes β-caryophyllene and β-myrcene, most preferred in the headache and ID Migraine™ groups. This could reflect the potent analgesic, anti-inflammatory, and anti-emetic properties of THC, with anti-inflammatory and analgesic properties of β-caryophyllene and β-myrcene. Opiates/opioids were most commonly substituted with cannabis. Prospective studies are needed, but results may provide early insight into optimizing crossbred cannabis strains, synergistic biochemical profiles, dosing, and patterns of use in the treatment of headache, migraine, and chronic pain syndromes.

Cancer and Complementary Therapies: Current Trends in Survivors' Interest and Use

Background. Cancer survivors use complementary therapies (CTs) for a variety of reasons; however, with interest and use reportedly on the rise and a widening range of products and practices available, there is a need to establish trends in and drivers of interest. We aimed to determine (1) frequencies of use, level of interest, and barriers for 30 specific CTs and (2) whether physical symptoms, perceived stress (PS), or spiritual well-being were related to interest levels. Method. A total of 212 cancer outpatients were surveyed at the Tom Baker Cancer Centre in Calgary, Canada. Results. Overall, up to 75% of survivors already used some form of CTs since their diagnosis. The most highly used were the following: vitamins B12 and D, multivitamins, calcium, and breathing and relaxation exercises. Those who had not used CTs indicated highest interest in massage, vitamin B12, breathing and relaxation, mindfulness-based stress reduction, and antioxidants. The most frequently reported barriers for all CTs were not knowing enough about what a therapy was and not having enough evidence on whether it worked. High PS predicted higher interest for all CTs, but spirituality was not significantly related to any. Physical symptoms, anxiety, and depression were significant predictors of interest for some CTs. Conclusion. These findings provide a blueprint for future clinical efficacy trials and highlight the need for clinical practice guidelines.

Medical marijuana in pediatric oncology: A review of the evidence and implications for practice

Medical marijuana (MM) has become increasingly legal at the state level and accessible to children with serious illness. Pediatric patients with cancer may be particularly receptive to MM, given purported benefits in managing cancer-related symptoms. In this review, we examine the evidence for MM as a supportive care agent in pediatric oncology. We describe the current legal status of MM, mechanism of action, common formulations, and potential benefits versus risks for pediatric oncology patients. We offer suggestions for how providers might approach MM requests. Throughout, we comment on avenues for future investigation on this growing trend in supportive care.

Cannabinoids for nausea and vomiting related to chemotherapy: Overview of systematic reviews

Nausea and vomiting are common and distressing adverse events of chemotherapy. This review focuses on the findings and quality of systematic reviews (SRs) of cannabinoids for chemotherapy-induced nausea and vomiting (CINV). Review of SRs, a systematic literature search, was conducted in several electronic databases and included SRs evaluating cannabinoids for CINV in cancer patients. Methodological quality and quality of reporting were evaluated by AMSTAR and PRISMA, respectively. Initial search retrieved 2,206 records, and 5 SRs were included. On the basis of findings of the sole SR judged as high methodological quality, cannabinoids seem to be more effective than placebo, equal to prochlorperazine for reducing CINV, and to be preferred by patients. The response to different combinations of antiemetic agents seems to be equal to 1 antiemetic alone. The average of AMSTAR score was 5, and the average of PRISMA score was 13.2. Cannabinoids represent a valuable option for treating CINV, despite the adverse events related to treatment, such as drowsiness and cognitive impairment. There is no good quality evidence to recommend or not the use of cannabinoids for CINV. More studies are still needed to evaluate the effectiveness of cannabinoids when compared with modern antiemetics.

Is cannabis treatment for anxiety, mood, and related disorders ready for prime time?

Anxiety and related disorders are the most common mental conditions affecting the North American population. Despite their established efficacy, first-line antidepressant treatments are associated with significant side effects, leading many afflicted individuals to seek alternative treatments. Cannabis is commonly viewed as a natural alternative for a variety of medical and mental health conditions. Currently, anxiety ranks among the top five medical symptoms for which North Americans report using medical marijuana. However, upon careful review of the extant treatment literature, the anxiolytic effects of cannabis in clinical populations are surprisingly not well-documented. The effects of cannabis on anxiety and mood symptoms have been examined in healthy populations and in several small studies of synthetic cannabinoid agents but there are currently no studies which have examined the effects of the cannabis plant on anxiety and related disorders. In light of the rapidly shifting landscape regarding the legalization of cannabis for medical and recreational purposes, it is important to highlight the significant disconnect between the scientific literature, public opinion, and related policies. The aim of this article is to provide a comprehensive review of the current cannabis treatment literature, and to identify the potential for cannabis to be used as a therapeutic intervention for anxiety, mood, and related disorders. Searches of five electronic databases were conducted (PubMed, MEDLINE, Web of Science, PsychINFO, and Google Scholar), with the most recent in February 2017. The effects of cannabis on healthy populations and clinical psychiatric samples will be discussed, focusing primarily on anxiety and mood disorders.

Cannabis use among patients at a comprehensive cancer center in a state with legalized medicinal and recreational use

BACKGROUND

Cannabis is purported to alleviate symptoms related to cancer treatment, although the patterns of use among cancer patients are not well known. This study was designed to determine the prevalence and methods of use among cancer patients, the perceived benefits, and the sources of information in a state with legalized cannabis.

METHODS

A cross‐sectional, anonymous survey of adult cancer patients was performed at a National Cancer Institute–designated cancer center in Washington State. Random urine samples for tetrahydrocannabinol provided survey validation.

RESULTS

Nine hundred twenty‐six of 2737 eligible patients (34%) completed the survey, and the median age was 58 years (interquartile range [IQR], 46‐66 years). Most had a strong interest in learning about cannabis during treatment (6 on a 1‐10 scale; IQR, 3‐10) and wanted information from cancer providers (677 of 911 [74%]). Previous use was common (607 of 926 [66%]); 24% (222 of 926) used cannabis in the last year, and 21% (192 of 926) used cannabis in the last month. Random urine samples found similar percentages of users who reported weekly use (27 of 193 [14%] vs 164 of 926 [18%]). Active users inhaled (153 of 220 [70%]) or consumed edibles (154 of 220 [70%]); 89 (40%) used both modalities. Cannabis was used primarily for physical (165 of 219 [75%]) and neuropsychiatric symptoms (139 of 219 [63%]). Legalization significantly increased the likelihood of use in more than half of the respondents.

CONCLUSIONS

This study of cancer patients in a state with legalized cannabis found high rates of active use across broad subgroups, and legalization was reported to be important in patients' decision to use. Cancer patients desire but are not receiving information about cannabis use during their treatment from oncology providers. Cancer 2017;123:4488‐97. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made.

Cannabis use is common among patients receiving treatment at a large cancer center in a state with legalized recreational and medical cannabis. Active use is reported across broad demographic and diagnostic cancer subgroups, and legalization is reported to be important in patients' decision to use.

Current Status and Prospects for Cannabidiol Preparations as New Therapeutic Agents

States and the federal government are under growing pressure to legalize the use of cannabis products for medical purposes in the United States. Sixteen states have legalized (or decriminalized possession of) products high in cannabidiol (CBD) and with restricted ∆(9) -tetrahydrocannabinol (∆(9) -THC) content. In most of these states, the intent is for use in refractory epileptic seizures in children, but in a few states, the indications are broader. This review provides an overview of the pharmacology and toxicology of CBD; summarizes some of the regulatory, safety, and cultural issues relevant to the further exploitation of its antiepileptic or other pharmacologic activities; and assesses the current status and prospects for clinical development of CBD and CBD-rich preparations for medical use in the United States. Unlike Δ(9) -THC, CBD elicits its pharmacologic effects without exerting any significant intrinsic activity on the cannabinoid receptors, whose activation results in the psychotropic effects characteristic of Δ(9) -THC, and CBD possesses several pharmacologic activities that give it a high potential for therapeutic use. CBD exhibits neuroprotective, antiepileptic, anxiolytic, antipsychotic, and antiinflammatory properties. In combination with Δ(9) -THC, CBD has received regulatory approvals in several European countries and is currently under study in trials registered by the U.S. Food and Drug Administration in the United States. A number of states have passed legislation to allow for the use of CBD-rich, limited Δ(9) -THC-content preparations of cannabis for certain pathologic conditions. CBD is currently being studied in several clinical trials and is at different stages of clinical development for various medical indications. Judging from clinical findings reported so far, CBD and CBD-enriched preparations have great potential utility, but uncertainties regarding sourcing, long-term safety, abuse potential, and regulatory dilemmas remain.

A review of oral cannabinoids and medical marijuana for the treatment of chemotherapy-induced nausea and vomiting: a focus on pharmacokinetic variability and pharmacodynamics

Purpose

Oral cannabinoids (i.e., dronabinol, nabilone) containing the active component of marijuana, delta(Δ)9-tetrahydrocannabinol (THC), are available for the treatment of chemotherapy-induced nausea and vomiting (CINV) in patients with cancer who have failed to adequately respond to conventional antiemetic therapy. The aim of this article is to provide an overview of the efficacy, pharmacokinetics (PK), pharmacodynamics (PD), and safety of oral cannabinoids for patients with CINV.

Methods

A PubMed search of the English-language literature available through 4 January 2017 was conducted to identify relevant articles for inclusion in the review.

Results

Oral cannabinoids have been shown to have similar or improved efficacy compared with conventional antiemetics for the resolution of nausea and/or vomiting in patients with cancer. However, oral THC has high PK variability, with variability in oral dronabinol peak plasma concentrations (C_max) estimated between 150 and 200%. A new oral dronabinol solution has decreased intraindividual variability (area under the curve) vs oral dronabinol capsules. Further, oral THC has a slower time to C_max compared with THC administered intravenously (IV) or by smoking, and a lower systemic availability than IV or smoked THC. The PD profile (e.g., “high”) of oral THC differs from that of IV or smoked THC in healthy individuals. Oral cannabinoids are associated with greater incidence of adverse effects compared with conventional antiemetic therapy or placebo (e.g., dizziness, hypotension, and dysphoria or depression).

Conclusions

A new formulation of oral cannabinoids (i.e., dronabinol oral solution) minimized the PK/PD variability currently observed with capsule formulations.

Role of cannabis in digestive disorders

Cannabis sativa, a subspecies of the Cannabis plant, contains aromatic hydrocarbon compounds called cannabinoids. [INCREMENT]-Tetrahydrocannabinol is the most abundant cannabinoid and is the main psychotropic constituent. Cannabinoids activate two types of G-protein-coupled cannabinoid receptors: cannabinoid type 1 receptor and cannabinoid type 2 receptor. There has been ongoing interest and development in research to explore the therapeutic potential of cannabis. [INCREMENT]-Tetrahydrocannabinol exerts biological functions on the gastrointestinal (GI) tract. Cannabis has been used for the treatment of GI disorders such as abdominal pain and diarrhea. The endocannabinoid system (i.e. endogenous circulating cannabinoids) performs protective activities in the GI tract and presents a promising therapeutic target against various GI conditions such as inflammatory bowel disease (especially Crohn's disease), irritable bowel syndrome, and secretion and motility-related disorders. The present review sheds light on the role of cannabis in the gut, liver, and pancreas and also on other GI symptoms, such as nausea and vomiting, cannabinoid hyperemesis syndrome, anorexia, weight loss, and chronic abdominal pain. Although the current literature supports the use of marijuana for the treatment of digestive disorders, the clinical efficacy of cannabis and its constituents for various GI disorders remains unclear.

A user's guide to cannabinoid therapies in oncology

"Cannabinoid" is the collective term for a group of chemical compounds that either are derived from the Cannabis plant, are synthetic analogues, or occur endogenously. Although cannabinoids interact mostly at the level of the currently recognized cannabinoid receptors, they might have cross reactivity, such as at opioid receptors. Patients with malignant disease represent a cohort within health care that have some of the greatest unmet needs despite the availability of a plethora of guideline-driven disease-modulating treatments and pain and symptom management options. Cannabinoid therapies are varied and versatile, and can be offered as pharmaceuticals (nabilone, dronabinol, and nabiximols), dried botanical material, and edible organic oils infused with cannabis extracts. Cannabinoid therapy regimens can be creative, involving combinations of all of the aforementioned modalities. Patients with malignant disease, at all points of their disease trajectory, could be candidates for cannabinoid therapies whether as monotherapies or as adjuvants. The most studied and established roles for cannabinoid therapies include pain, chemotherapy-induced nausea and vomiting, and anorexia. Moreover, given their breadth of activity, cannabinoids could be used to concurrently optimize the management of multiple symptoms, thereby reducing overall polypharmacy. The use of cannabinoid therapies could be effective in improving quality of life and possibly modifying malignancy by virtue of direct effects and in improving compliance or adherence with disease-modulating treatments such as chemotherapy and radiation therapy.

State of the evidence: Cannabinoids and cancer pain-A systematic review

BACKGROUND AND PURPOSE

Cannabinoids are widely used to alleviate intractable symptoms such as pain, nausea, and muscle spasticity. The purpose of this review was to ascertain the current state of the science regarding use of cannabinoids for cancer pain.

METHODS

Four electronic databases were searched for randomized control trials of cannabinoids and cancer pain. Studies included examined the analgesic effects of cannabinoids for cancer pain. Methodological quality was assessed using the Jadad scale.

CONCLUSIONS

Eight randomized control trials met the inclusion criteria for review. Most trials found analgesic effects from cannabinoids when compared to placebo, although not all associations reached statistical significance. The analgesic effects of cannabinoids were also limited by dose-dependent side effects. Side effects most commonly reported were changes in cognition, sedation, and dizziness.

IMPLICATIONS FOR PRACTICE

There is evidence that cannabinoids are effective adjuvants for cancer pain not completely relieved by opioid therapy, but there is a dearth of high-quality studies to support a stronger conclusion. Cannabinoids appear to be safe in low and medium doses. Methodological limitations of the trials limited the ability to make sound conclusions. Further research is warranted before efficacy, safety, and utility of cannabinoids for cancer pain can be determined.

Practical Aspects of Discussing Marijuana in a New Era

The use of marijuana for the treatment of medical conditions is a highly controversial topic. Misconceptions by both patients and providers concerning the safety of and evidence-based indications for marijuana can complicate treatment planning and outcomes. Maintaining skills such as motivational interviewing, providing evidence-based informed consent, and increasing access to care remain top priorities for providing quality patient care. The goal of this article is to offer guidance to clinical providers who are adapting to the changing realities of medical marijuana and legalized recreational marijuana.

Cannabinoids and GI Disorders: Endogenous and Exogenous

OPINION STATEMENT

Despite the political and social controversy affiliated with it, the medical community must come to the realization that cannabinoids exist as a ubiquitous signaling system in many organ systems. Our understanding of cannabinoids and how they relate not only to homeostasis but also in disease states must be furthered through research, both clinically and in the laboratory. The identification of the cannabinoid receptors in the early 1990s have provided us with the perfect target of translational research. Already, much has been done with cannabinoids and the nervous system. Here, we explore the implications it has for the gastrointestinal tract. Most therapeutics currently on the market presently target only one aspect of the cannabinoid system. Our main purpose here is to highlight areas of research and potential avenues of discovery that the cannabinoid system has yet to reveal.

From Phytocannabinoids to Cannabinoid Receptors and Endocannabinoids: Pleiotropic Physiological and Pathological Roles Through Complex Pharmacology

Apart from having been used and misused for at least four millennia for, among others, recreational and medicinal purposes, the cannabis plant and its most peculiar chemical components, the plant cannabinoids (phytocannabinoids), have the merit to have led humanity to discover one of the most intriguing and pleiotropic endogenous signaling systems, the endocannabinoid system (ECS). This review article aims to describe and critically discuss, in the most comprehensive possible manner, the multifaceted aspects of 1) the pharmacology and potential impact on mammalian physiology of all major phytocannabinoids, and not only of the most famous one Δ9-tetrahydrocannabinol, and 2) the adaptive pro-homeostatic physiological, or maladaptive pathological, roles of the ECS in mammalian cells, tissues, and organs. In doing so, we have respected the chronological order of the milestones of the millennial route from medicinal/recreational cannabis to the ECS and beyond, as it is now clear that some of the early steps in this long path, which were originally neglected, are becoming important again. The emerging picture is rather complex, but still supports the belief that more important discoveries on human physiology, and new therapies, might come in the future from new knowledge in this field.

Endocannabinoid-related lipids are increased during an episode of cyclic vomiting syndrome

BACKGROUND

The endocannabinoid system and the hypothalamic-pituitary-adrenal axis are important neuromodulators of nausea and vomiting. This led us to hypothesize that patients with cyclic vomiting syndrome (CVS) have lower serum endocannabinoids (eCBs) and higher salivary cortisol and alpha amylase.

METHODS

Serum eCBs and related lipids, N-oleoylethanolamine (OEA) and N-palmitoylethanolamide (PEA), and salivary cortisol, and alpha amylase (index of sympathetic nervous system activity) were measured in 22 CVS patients (age 40 ± 11, female = 17) in the well and sick phases and 12 matched controls (age 37 ± 12, female = 10).

KEY RESULTS

Contrary to our hypothesis, serum concentrations of the eCBs were not different among the study groups. However, serum concentrations of OEA and PEA were significantly higher during the sick than well phase in CVS patients (p = 0.001 and p = 0.04). There were positive correlations between serum PEA and nausea scores in the sick phase (Pearson's rho = 0.48, p = 0.036) and between serum OEA and poor sleep quality in patients (Pearson's rho = 0.7, p = 0.0005). Salivary cortisol and alpha amylase were not different between patients and controls, but subgroup analysis revealed that both were significantly higher in marijuana users compared to non-users during the sick phase (p = 0.04 and 0.03, respectively).

CONCLUSIONS & INFERENCES

These data demonstrate that eCB-related lipids, OEA and PEA, are mobilized in the sick phase of CVS and are positively correlated with several of the symptoms of a CVS episode. These data also suggest the hypothesis that chronic marijuana use results in enhanced stress responses during CVS.

Dronabinol for chemotherapy-induced nausea and vomiting unresponsive to antiemetics

Chemotherapy-induced nausea and vomiting (CINV) is one of the most common symptoms feared by patients, but may be prevented or lessened with appropriate medications. Several antiemetic options exist to manage CINV. Corticosteroids, serotonin receptor antagonists, and neurokinin receptor antagonists are the classes most commonly used in the prevention of CINV. There are many alternative drug classes utilized for the prevention and management of CINV such as antihistamines, benzodiazepines, anticonvulsants, cannabinoids, and dopamine receptor antagonists. Medications belonging to these classes generally have lower efficacy and are associated with more adverse effects. They are also not as well studied compared to the aforementioned agents. This review will focus on dronabinol, a member of the cannabinoid class, and its role in CINV. Cannabis sativa L. (also known as marijuana) contains naturally occurring delta-9-tetrahydrocannibinol (delta-9-THC). The synthetic version of delta-9-THC is the active ingredient in dronabinol that makes dronabinol an orally active cannabinoid. Evidence for clinical efficacy of dronabinol will be analyzed in this review as monotherapy, in combination with ondansetron, and in combination with prochlorperazine.

Integrating cannabis into clinical cancer care

Cannabis species have been used as medicine for thousands of years; only since the 1940s has the plant not been widely available for medical use. However, an increasing number of jurisdictions are making it possible for patients to obtain the botanical for medicinal use. For the cancer patient, cannabis has a number of potential benefits, especially in the management of symptoms. Cannabis is useful in combatting anorexia, chemotherapy-induced nausea and vomiting, pain, insomnia, and depression. Cannabis might be less potent than other available antiemetics, but for some patients, it is the only agent that works, and it is the only antiemetic that also increases appetite. Inhaled cannabis is more effective than placebo in ameliorating peripheral neuropathy in a number of conditions, and it could prove useful in chemotherapy-induced neuropathy. A pharmacokinetic interaction study of vaporized cannabis in patients with chronic pain on stable doses of sustained-release opioids demonstrated no clinically significant change in plasma opiates, while suggesting the possibility of synergistic analgesia. Aside from symptom management, an increasing body of in vitro and animal-model studies supports a possible direct anticancer effect of cannabinoids by way of a number of different mechanisms involving apoptosis, angiogenesis, and inhibition of metastasis. Despite an absence of clinical trials, abundant anecdotal reports that describe patients having remarkable responses to cannabis as an anticancer agent, especially when taken as a high-potency orally ingested concentrate, are circulating. Human studies should be conducted to address critical questions related to the foregoing effects.

Adherence to Medical Cannabis Among Licensed Patients in Israel

Objectives: To evaluate adherence among Israeli patients who are licensed to use medical cannabis and to identify factors associated with adherence to medical cannabis. Methods: Ninety-five novice licensed patients were interviewed for this cross-sectional study. The questionnaire measured demographics, the perceived patient-physician relationship, and the level of patients' active involvement in their healthcare. In addition, patients were queried about adverse effect(s) and about their overall satisfaction from this medical treatment. Results: Eighty percent (n=76) has been identified as adherent to medical cannabis use. Variables found associated with adherence were "country of origin" (immigrant status), "type of illness" (cancer vs. non-cancer), and "experiencing adverse effect(s)." Three predictors of adherence were found significant in a logistic regression model: "type of illness" (odds ratio [OR] 0.101), patient-physician relationship (OR 1.406), and level of patient activation (OR 1.132). 71.5% rated themselves being "completely satisfied" or "satisfied" from medical cannabis use. Conclusions: Our findings show a relatively high adherence rate for medical cannabis, as well as relative safety and high satisfaction among licensed patients. Additionally indicated is the need to develop and implement standardized education about this evolving field-to both patients and physicians.

Cannabinoids for nausea and vomiting in adults with cancer receiving chemotherapy

BACKGROUND

Cannabis has a long history of medicinal use. Cannabis-based medications (cannabinoids) are based on its active element, delta-9-tetrahydrocannabinol (THC), and have been approved for medical purposes. Cannabinoids may be a useful therapeutic option for people with chemotherapy-induced nausea and vomiting that respond poorly to commonly used anti-emetic agents (anti-sickness drugs). However, unpleasant adverse effects may limit their widespread use.

OBJECTIVES

To evaluate the effectiveness and tolerability of cannabis-based medications for chemotherapy-induced nausea and vomiting in adults with cancer.

SEARCH METHODS

We identified studies by searching the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO and LILACS from inception to January 2015. We also searched reference lists of reviews and included studies. We did not restrict the search by language of publication.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared a cannabis-based medication with either placebo or with a conventional anti-emetic in adults receiving chemotherapy.

DATA COLLECTION AND ANALYSIS

At least two review authors independently conducted eligibility and risk of bias assessment, and extracted data. We grouped studies based on control groups for meta-analyses conducted using random effects. We expressed efficacy and tolerability outcomes as risk ratio (RR) with 95% confidence intervals (CI).

MAIN RESULTS

We included 23 RCTs. Most were of cross-over design, on adults undergoing a variety of chemotherapeutic regimens ranging from moderate to high emetic potential for a variety of cancers. The majority of the studies were at risk of bias due to either lack of allocation concealment or attrition. Trials were conducted between 1975 and 1991. No trials involved comparison with newer anti-emetic drugs such as ondansetron. Comparison with placebo People had more chance of reporting complete absence of vomiting (3 trials; 168 participants; RR 5.7; 95% CI 2.6 to 12.6; low quality evidence) and complete absence of nausea and vomiting (3 trials; 288 participants; RR 2.9; 95% CI 1.8 to 4.7; moderate quality evidence) when they received cannabinoids compared with placebo. The percentage of variability in effect estimates that was due to heterogeneity rather than chance was not important (I(2) = 0% in both analyses).People had more chance of withdrawing due to an adverse event (2 trials; 276 participants; RR 6.9; 95% CI 1.96 to 24; I(2) = 0%; very low quality evidence) and less chance of withdrawing due to lack of efficacy when they received cannabinoids, compared with placebo (1 trial; 228 participants; RR 0.05; 95% CI 0.0 to 0.89; low quality evidence). In addition, people had more chance of 'feeling high' when they received cannabinoids compared with placebo (3 trials; 137 participants; RR 31; 95% CI 6.4 to 152; I(2) = 0%).People reported a preference for cannabinoids rather than placebo (2 trials; 256 participants; RR 4.8; 95% CI 1.7 to 13; low quality evidence). Comparison with other anti-emetics There was no evidence of a difference between cannabinoids and prochlorperazine in the proportion of participants reporting no nausea (5 trials; 258 participants; RR 1.5; 95% CI 0.67 to 3.2; I(2) = 63%; low quality evidence), no vomiting (4 trials; 209 participants; RR 1.11; 95% CI 0.86 to 1.44; I(2) = 0%; moderate quality evidence), or complete absence of nausea and vomiting (4 trials; 414 participants; RR 2.0; 95% CI 0.74 to 5.4; I(2) = 60%; low quality evidence). Sensitivity analysis where the two parallel group trials were pooled after removal of the five cross-over trials showed no difference (RR 1.1; 95% CI 0.70 to 1.7) with no heterogeneity (I(2) = 0%).People had more chance of withdrawing due to an adverse event (5 trials; 664 participants; RR 3.9; 95% CI 1.3 to 12; I(2) = 17%; low quality evidence), due to lack of efficacy (1 trial; 42 participants; RR 3.5; 95% CI 1.4 to 8.9; very low quality evidence) and for any reason (1 trial; 42 participants; RR 3.5; 95% CI 1.4 to 8.9; low quality evidence) when they received cannabinoids compared with prochlorperazine.People had more chance of reporting dizziness (7 trials; 675 participants; RR 2.4; 95% CI 1.8 to 3.1; I(2) = 12%), dysphoria (3 trials; 192 participants; RR 7.2; 95% CI 1.3 to 39; I(2) = 0%), euphoria (2 trials; 280 participants; RR 18; 95% CI 2.4 to 133; I(2) = 0%), 'feeling high' (4 trials; 389 participants; RR 6.2; 95% CI 3.5 to 11; I(2) = 0%) and sedation (8 trials; 947 participants; RR 1.4; 95% CI 1.2 to 1.8; I(2) = 31%), with significantly more participants reporting the incidence of these adverse events with cannabinoids compared with prochlorperazine.People reported a preference for cannabinoids rather than prochlorperazine (7 trials; 695 participants; RR 3.3; 95% CI 2.2 to 4.8; I(2) = 51%; low quality evidence).In comparisons with metoclopramide, domperidone and chlorpromazine, there was weaker evidence, based on fewer trials and participants, for higher incidence of dizziness with cannabinoids.Two trials with 141 participants compared an anti-emetic drug alone with a cannabinoid added to the anti-emetic drug. There was no evidence of differences between groups; however, the majority of the analyses were based on one small trial with few events. Quality of the evidence The trials were generally at low to moderate risk of bias in terms of how they were designed and do not reflect current chemotherapy and anti-emetic treatment regimens. Furthermore, the quality of evidence arising from meta-analyses was graded as low for the majority of the outcomes analysed, indicating that we are not very confident in our ability to say how well the medications worked. Further research is likely to have an important impact on the results.

AUTHORS' CONCLUSIONS

Cannabis-based medications may be useful for treating refractory chemotherapy-induced nausea and vomiting. However, methodological limitations of the trials limit our conclusions and further research reflecting current chemotherapy regimens and newer anti-emetic drugs is likely to modify these conclusions.

Improving Quality of Life With Nabilone During Radiotherapy Treatments for Head and Neck Cancers

Objectives:

Patients treated for head and neck carcinomas experience a significant deterioration of their quality of life during treatments because of severe side effects. Nabilone has many properties that could alleviate symptoms caused by radiotherapy and improve patients’ quality of life. The aim of the present study was to compare the effects of nabilone versus placebo on the quality of life and side effects during radiotherapy for head and neck carcinomas.

Methods:

Fifty-six patients were randomized to nabilone or placebo. Patients filled the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 and the EORTC QLQ-H&N35; three independent questionnaires assessing appetite, nausea, and toxicity; and a visual analog scale for pain. These data were collected before radiotherapy, each week during radiotherapy, and 4 weeks after radiotherapy. Patients were weighed every week.

Results:

Nabilone did not lengthen the time necessary for a 15% deterioration of quality of life ( P = .4279), and it was not better than placebo for relieving symptoms like pain ( P = .6048), nausea ( P = .7105), loss of appetite ( P = .3295), weight ( P = .1454), mood ( P = .3214), and sleep ( P = .4438).

Conclusion:

At the dosage used, nabilone was not potent enough to improve the patients’ quality of life over placebo.

Public opinion and medical cannabis policies: examining the role of underlying beliefs and national medical cannabis policies

Background

Debate about medical cannabis legalization are typically informed by three beliefs: (1) cannabis has medical effects, (2) medical cannabis is addictive and (3) medical cannabis legalization leads to increased used of cannabis for recreational purposes (spillover effects). We examined how strongly these beliefs are associated with public support for medical cannabis legalization and whether this association differs across divergent medical cannabis policy regimes.

Methods

Robust regression analysis was used to analyse data derived from two nationally representative samples of adults participating in comparable cross-sectional online surveys in one country where medical cannabis smoking is illegal (Norway, n = 2175, 51 % male) and in one country where medical cannabis smoking is legal (Israel, n = 648, 49 % male).

Results

The belief that cannabis has medical benefits was more strongly related to support for medical cannabis legalization than were beliefs about addiction and spillover effects. While the support for medical cannabis legalization was stronger in Israel than in Norway (78 vs. 51 %, p < 0.01), the belief variables had, in general, more impact on the policy stand in Norway.

Conclusion

The belief that cannabis has medical benefits is particularly salient for support for medical cannabis legalization. It is possible that the recent surge in evidence supporting the medical benefits of cannabis will increase the belief about medical benefits of cannabis in the general population which may in turn increase public support for medical cannabis legalization. Results also suggest that once medical cannabis is legalized, factors beyond cannabis-specific beliefs will increasingly influence medical cannabis legalization support. These conclusions are, however, only suggestive as the current study is based on cross-sectional data. Hopefully, future research will be able to capitalize on changes in medical cannabis policies and conduct longitudinal studies that enable an examination of the causal relation between public opinion and medical cannabis policy changes.

Safety and Toxicology of Cannabinoids

There is extensive research on the safety, toxicology, potency, and therapeutic potential of cannabis. However, uncertainty remains facilitating continued debate on medical and recreational cannabis policies at the state and federal levels. This review will include a brief description of cannabinoids and the endocannabinoid system; a summary of the acute and long-term effects of cannabis; and a discussion of the therapeutic potential of cannabis. The conclusions about safety and efficacy will then be compared with the current social and political climate to suggest future policy directions and general guidelines.

Medical marijuana patient counseling points for health care professionals based on trends in the medical uses, efficacy, and adverse effects of cannabis-based pharmaceutical drugs

The purpose of this report is to present a review of the medical uses, efficacy, and adverse effects of the three approved cannabis-based medications and ingested marijuana. A literature review was conducted utilizing key search terms: dronabinol, nabilone, nabiximols, cannabis, marijuana, smoke, efficacy, toxicity, cancer, multiple sclerosis, nausea, vomiting, appetite, pain, glaucoma, and side effects. Abstracts of the included literature were reviewed, analyzed, and organized to identify the strength of evidence in medical use, efficacy, and adverse effects of the approved cannabis-based medications and medical marijuana. A total of 68 abstracts were included for review. Dronabinol's (Marinol) most common medical uses include weight gain, chemotherapy-induced nausea and vomiting (CINV), and neuropathic pain. Nabiximol's (Sativex) most common medical uses include spasticity in multiple sclerosis (MS) and neuropathic pain. Nabilone's (Cesamet) most common medical uses include CINV and neuropathic pain. Smoked marijuana's most common medical uses include neuropathic pain and glaucoma. Orally ingested marijuana's most common medical uses include improving sleep, reducing neuropathic pain, and seizure control in MS. In general, all of these agents share similar medical uses. The reported adverse effects of the three cannabis-based medications and marijuana show a major trend in central nervous system (CNS)-related adverse effects along with cardiovascular and respiratory related adverse effects. Marijuana shares similar medical uses with the approved cannabis-based medications dronabinol (Marinol), nabiximols (Sativex), and nabilone (Cesamet), but the efficacy of marijuana for these medical uses has not been fully determined due to limited and conflicting literature. Medical marijuana also has similar adverse effects as the FDA-approved cannabis-based medications mainly consisting of CNS related adverse effects but also including cardiovascular and respiratory related adverse effects. Finally, insufficient higher-order evidence to support the widespread use of medical marijuana was found, but a limited amount of moderate-level evidence supports its use in pain and seizure management.

Cannabinoid Ligands and Alcohol Addiction: A Promising Therapeutic Tool or a Humbug?

The vast therapeutic potential of cannabinoids of both synthetic and plant-derived origins currently makes these compounds the focus of a growing interest. Although cannabinoids are still illicit drugs, their possible clinical usefulness, including treatment of acute or neuropathic pain, have been suggested by several studies. In addition, some observations indicate that cannabinoid receptor antagonists may be useful for the treatment of alcohol dependence and addiction, which is a major health concern worldwide. While the synergism between alcohol and cannabinoid agonists (in various forms) creates undesirable side effects when the two are consumed together, the administration of CB1 antagonists leads to a significant reduction in alcohol consumption. Furthermore, cannabinoid antagonists also mitigate alcohol withdrawal symptoms. Herein, we present an overview of studies focusing on the effects of cannabinoid ligands (agonists and antagonists) during acute or chronic consumption of ethanol.

Comprehensive Review of Medicinal Marijuana, Cannabinoids, and Therapeutic Implications in Medicine and Headache: What a Long Strange Trip It's Been …

BACKGROUND

The use of cannabis, or marijuana, for medicinal purposes is deeply rooted though history, dating back to ancient times. It once held a prominent position in the history of medicine, recommended by many eminent physicians for numerous diseases, particularly headache and migraine. Through the decades, this plant has taken a fascinating journey from a legal and frequently prescribed status to illegal, driven by political and social factors rather than by science. However, with an abundance of growing support for its multitude of medicinal uses, the misguided stigma of cannabis is fading, and there has been a dramatic push for legalizing medicinal cannabis and research. Almost half of the United States has now legalized medicinal cannabis, several states have legalized recreational use, and others have legalized cannabidiol-only use, which is one of many therapeutic cannabinoids extracted from cannabis. Physicians need to be educated on the history, pharmacology, clinical indications, and proper clinical use of cannabis, as patients will inevitably inquire about it for many diseases, including chronic pain and headache disorders for which there is some intriguing supportive evidence.

OBJECTIVE

To review the history of medicinal cannabis use, discuss the pharmacology and physiology of the endocannabinoid system and cannabis-derived cannabinoids, perform a comprehensive literature review of the clinical uses of medicinal cannabis and cannabinoids with a focus on migraine and other headache disorders, and outline general clinical practice guidelines.

CONCLUSION

The literature suggests that the medicinal use of cannabis may have a therapeutic role for a multitude of diseases, particularly chronic pain disorders including headache. Supporting literature suggests a role for medicinal cannabis and cannabinoids in several types of headache disorders including migraine and cluster headache, although it is primarily limited to case based, anecdotal, or laboratory-based scientific research. Cannabis contains an extensive number of pharmacological and biochemical compounds, of which only a minority are understood, so many potential therapeutic uses likely remain undiscovered. Cannabinoids appear to modulate and interact at many pathways inherent to migraine, triptan mechanisms ofaction, and opiate pathways, suggesting potential synergistic or similar benefits. Modulation of the endocannabinoid system through agonism or antagonism of its receptors, targeting its metabolic pathways, or combining cannabinoids with other analgesics for synergistic effects, may provide the foundation for many new classes of medications. Despite the limited evidence and research suggesting a role for cannabis and cannabinoids in some headache disorders, randomized clinical trials are lacking and necessary for confirmation and further evaluation.

Narrative review of the safety and efficacy of marijuana for the treatment of commonly state-approved medical and psychiatric disorders

The present investigation aimed to provide an objective narrative review of the existing literature pertaining to the benefits and harms of marijuana use for the treatment of the most common medical and psychological conditions for which it has been allowed at the state level. Common medical conditions for which marijuana is allowed (i.e., those conditions shared by at least 80 percent of medical marijuana states) were identified as: Alzheimer’s disease, amyotrophic lateral sclerosis, cachexia/wasting syndrome, cancer, Crohn’s disease, epilepsy and seizures, glaucoma, hepatitis C virus, human immunodeficiency virus/acquired immunodeficiency syndrome, multiple sclerosis and muscle spasticity, severe and chronic pain, and severe nausea. Post-traumatic stress disorder was also included in the review, as it is the sole psychological disorder for which medical marijuana has been allowed. Studies for this narrative review were included based on a literature search in PsycINFO, MEDLINE, and Google Scholar. Findings indicate that, for the majority of these conditions, there is insufficient evidence to support the recommendation of medical marijuana at this time. A significant amount of rigorous research is needed to definitively ascertain the potential implications of marijuana for these conditions. It is important for such work to not only examine the effects of smoked marijuana preparations, but also to compare its safety, tolerability, and efficacy in relation to existing pharmacological treatments.

Patterns of use of medical cannabis among Israeli cancer patients: a single institution experience

CONTEXT

The use of the cannabis plant (Cannabis sativa L.) for the palliative treatment of cancer patients has been legalized in multiple jurisdictions including Israel. Yet, not much is currently known regarding the efficacy and patterns of use of cannabis in this setting.

OBJECTIVES

To analyze the indications for the administration of cannabis among adult Israeli cancer patients and evaluate its efficacy.

METHODS

Efficacy and patterns of use of cannabis were evaluated using physician-completed application forms, medical files, and a detailed questionnaire in adult cancer patients treated at a single institution.

RESULTS

Of approximately 17,000 cancer patients seen, 279 (<1.7%) received a permit for cannabis from an authorized institutional oncologist. The median age of cannabis users was 60 years (range 19-93 years), 160 (57%) were female, and 234 (84%) had metastatic disease. Of 151 (54%) patients alive at six months, 70 (46%) renewed their cannabis permit. Renewal was more common among younger patients and those with metastatic disease. Of 113 patients alive and using cannabis at one month, 69 (61%) responded to the detailed questionnaire. Improvement in pain, general well-being, appetite, and nausea were reported by 70%, 70%, 60%, and 50%, respectively. Side effects were mild and consisted mostly of fatigue and dizziness.

CONCLUSION

Cannabis use is perceived as highly effective by some patients with advanced cancer and its administration can be regulated, even by local authorities. Additional studies are required to evaluate the efficacy of cannabis as part of the palliative treatment of cancer patients.

Medical marijuana for digestive disorders: high time to prescribe?

The use of recreational and medical marijuana is increasingly accepted by the general public in the United States. Along with growing interest in marijuana use has come an understanding of marijuana's effects on normal physiology and disease, primarily through elucidation of the human endocannabinoid system. Scientific inquiry into this system has indicated potential roles for marijuana in the modulation of gastrointestinal symptoms and disease. Some patients with gastrointestinal disorders already turn to marijuana for symptomatic relief, often without a clear understanding of the risks and benefits of marijuana for their condition. Unfortunately, that lack of understanding is shared by health-care providers. Marijuana's federal legal status as a Schedule I controlled substance has limited clinical investigation of its effects. There are also potential legal ramifications for physicians who provide recommendations for marijuana for their patients. Despite these constraints, as an increasing number of patients consider marijuana as a potential therapy for their digestive disorders, health-care providers will be asked to discuss the issues surrounding medical marijuana with their patients.

Cannabis for therapeutic purposes and public health and safety: a systematic and critical review

BACKGROUND

The use of Cannabis for Therapeutic Purposes (CTP) has recently become legal in many places. These policy and legal modifications may be related to changes in cannabis perceptions, availability and use and in the way cannabis is grown and sold. This may in turn have effects on public health and safety. To better understand the potential effects of CTP legalization on public health and safety, the current paper synthesizes and critically discusses the relevant literature.

METHODS

Twenty-eight studies were identified by a comprehensive search strategy, and their characteristics and main findings were systematically reviewed according to the following content themes: CTP and illegal cannabis use; CTP and other public health issues; CTP, crime and neighbourhood disadvantage.

RESULTS

The research field is currently limited by a lack of theoretical and methodological rigorous studies. The review shows that the most prevalent theme of investigation so far has been the relation between CTP and illegal cannabis use. In addition, the literature review shows that there is an absence of evidence to support many common concerns related to detrimental public health and safety effects of CTP legalization.

CONCLUSION

Although lack of evidence provides some reassurance that CTP legalization may not have posed a substantial threat to public health and safety, this conclusion needs to be examined in light of the limitations of studies conducted so far. Furthermore, as CTP policy continues to evolve, including incorporation of greater commercialization, it is possible that the full effects of CTP legalization have yet to take place. Ensuring study quality will allow future research to better investigate the complex role that CTP plays in relation to society at large, and public health and safety in particular.

Cannabidiol: pharmacology and potential therapeutic role in epilepsy and other neuropsychiatric disorders

To present a summary of current scientific evidence about the cannabinoid, cannabidiol (CBD) with regard to its relevance to epilepsy and other selected neuropsychiatric disorders. We summarize the presentations from a conference in which invited participants reviewed relevant aspects of the physiology, mechanisms of action, pharmacology, and data from studies with animal models and human subjects. Cannabis has been used to treat disease since ancient times. Δ(9) -Tetrahydrocannabinol (Δ(9) -THC) is the major psychoactive ingredient and CBD is the major nonpsychoactive ingredient in cannabis. Cannabis and Δ(9) -THC are anticonvulsant in most animal models but can be proconvulsant in some healthy animals. The psychotropic effects of Δ(9) -THC limit tolerability. CBD is anticonvulsant in many acute animal models, but there are limited data in chronic models. The antiepileptic mechanisms of CBD are not known, but may include effects on the equilibrative nucleoside transporter; the orphan G-protein-coupled receptor GPR55; the transient receptor potential of vanilloid type-1 channel; the 5-HT1a receptor; and the α3 and α1 glycine receptors. CBD has neuroprotective and antiinflammatory effects, and it appears to be well tolerated in humans, but small and methodologically limited studies of CBD in human epilepsy have been inconclusive. More recent anecdotal reports of high-ratio CBD:Δ(9) -THC medical marijuana have claimed efficacy, but studies were not controlled. CBD bears investigation in epilepsy and other neuropsychiatric disorders, including anxiety, schizophrenia, addiction, and neonatal hypoxic-ischemic encephalopathy. However, we lack data from well-powered double-blind randomized, controlled studies on the efficacy of pure CBD for any disorder. Initial dose-tolerability and double-blind randomized, controlled studies focusing on target intractable epilepsy populations such as patients with Dravet and Lennox-Gastaut syndromes are being planned. Trials in other treatment-resistant epilepsies may also be warranted. A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.

Bridging cross-cultural gaps: monitoring herbal use during chemotherapy in patients referred to integrative medicine consultation in Israel

INTRODUCTION

The high prevalence of the use of traditional herbs among patients with cancer is a cause for concern with regard to potentially adverse interactions with conventional oncology treatments. In this study, we explore herbal use among patients with cancer in northern Israel who are referred by their health care providers to complementary and traditional medicine (CTM) consultations provided to them within the conventional oncology department. The study's objectives were to identify which herbs patients use and to examine the scope of current research on the efficacy and safety regarding the identified herbs.

PATIENTS AND METHODS

Herbal use by patients receiving oncology care was assessed prospectively from July 2009 to July 2012 by integrative physicians (IPs) trained in herbal medicine. Historical, ethnobotanical, basic research, and clinical data regarding the identified herbs were explored by using a keyword search in PubMed and Middle Eastern ethnohistorical literature.

RESULTS

Disclosure of herbal use was reported by 154 of the 305 patients (50.5 %) interviewed by IPs. The use of 85 single herbs and 30 different herbal formulas was documented during the initial or follow-up IP assessments. Patients reported 14 quality of life-associated indications for herbal use. The ten most prevalent herbs displaying in vitro/in vivo anticancer activity and nine other herbs were preliminarily assessed concerning potential risks, safety, and interaction with chemotherapy.

CONCLUSIONS

Herbal use by patients with cancer in northern Israel is widespread and calls for further study in order to address issues of safety and effectiveness. We recommend constructing a multinational and multidisciplinary team of researchers with ethnopharmacological and clinical expertise that will explore the use of herbs among patients with cancer in a cross-cultural perspective attuned with patients' affinity to traditional herbal medicine.

Toward modulation of the endocannabinoid system for treatment of gastrointestinal disease: FAAHster but not "higher"

Cannabis has been used to treat various afflictions throughout the centuries, including nausea, vomiting, and pain. It has also been used recreationally for its psychotropic properties, which can include a pleasurable 'high' feeling and a decrease in anxiety and tension; however, other may experience dysphoria. Changes in cognition and psychomotor performance are also well-known with cannabis use. In recent years, our understanding of the endocannabinoid system (ECS) has progressed dramatically; the objective of identifying agents which may allow modulation of the ECS without significant psychotropic side effects may be possible. Inhibition of fatty acid amide hydrolase (FAAH), an important enzyme for the degradation of anandamide and other endogenous cannabinoids, is a promising target to achieve this goal. In this issue of Neurogastroenterology and Motility, Fichna and colleagues report on a novel selective FAAH inhibitor, PF-3845, with potent antinociceptive and antidiarrheal effects in a mouse model. In this context, we briefly review the components of the ECS, discuss pharmacologic targets for indirect cannabinoid receptor stimulation, and describe recent research with cannabinoids for gut disorders.