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1.
Epidemiological evidence demonstrates that cannabis use is associated with an increased risk of psychotic outcomes, and confirms a dose‐response relationship between the level of use and the risk of later psychosis. High‐potency cannabis and synthetic cannabinoids carry the greatest risk. Experimental administration of tetrahydrocannabinol, the active ingredient of cannabis, induces transient psychosis in normal subjects, but this effect can be ameliorated by co‐administration of cannabidiol. This latter is a constituent of traditional hashish, but is largely absent from modern high‐potency forms of cannabis. Argument continues over the extent to which genetic predisposition is correlated to, or interacts with, cannabis use, and what proportion of psychosis could be prevented by minimizing heavy use. As yet, there is not convincing evidence that cannabis use increases risk of other psychiatric disorders, but there are no such doubts concerning its detrimental effect on cognitive function. All of the negative aspects are magnified if use starts in early adolescence. Irrespective of whether use of cannabis is decriminalized or legalized, the evidence that it is a component cause of psychosis is now sufficient for public health messages outlining the risk, especially of regular use of high‐potency cannabis and synthetic cannabinoids.  相似文献   

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3.
To combat the coronaviruses and their novel variants, therapeutic drugs and the development of vaccines that are to be effective throughout human life are urgently needed. The endocannabinoid system (ECS) acts as a modulator in the activation of the microcirculation, immune system, and autonomic nervous system, along with controlling pharmacological functions such as emotional responses, homeostasis, motor functions, cognition, and motivation. The ECS contains endogenous cannabinoids, cannabinoid receptor (CBRs), and enzymes that regulate their biosynthesis, transport, and degradation. Moreover, phytocannabinoids and synthetic cannabinoids that mimic the action of endocannabinoids also play an essential role in the modulation of the ECS. Cannabinoids, the main constituents of cannabis (Cannabis sativa L.), are therapeutic compounds that have received international attention in the health field due to their therapeutic properties. Recently, they have been tested for the treatment of COVID-19 due to their antiviral properties. Indeed, cannabinoid-type compounds, and in particular cannabidiol (CBD), isolated from glandular trichomes found in the calyx of cannabis flowers with reported antiviral properties is hypothesized to be a therapeutic option in the ministration of SARS-CoV-2 consorted with COVID-19 disease. The relevant articles were determined from the database search published mainly in Web of Science, Google scholar, PubMed, Crossref, and ClinicalTrials.gov database during the pandemic period. The articles were evaluated for the therapeutic potentials, mechanisms of action of cannabinoids, the roles of the ECS in the immune system, impact of cannabinoids in SARS-CoV-2 septic, especially if they address the application of cannabinoids as drugs for the curability and management of SARS-CoV-2 and its novel variants. Although the evidence needed to be considered using cannabinoids in the control and treatment of viral diseases is currently in its infancy, they already offer an opportunity for clinicians due to their effects in relieving pain, improving appetite, and improving childhood epilepsy, especially in cancer and human immunodeficiency virus (HIV/AIDS) patients. In addition to these, the most recent scientific evidence emphasizes their use in the treatment of the coronavirus infected patients. In brief, all preclinic and clinic studies that have been reported show that, through the cannabinoid system, cannabinoids, particularly CBD, have many mechanisms that are effective in the treatment of patients infected by SARS-CoV-2. Thus, more extensive studies are necessary in this area to fully identify the effects of cannabinoids on SARS-CoV-2.  相似文献   

4.

Background

Chronic neuropathic pain affects 1%–2% of the adult population and is often refractory to standard pharmacologic treatment. Patients with chronic pain have reported using smoked cannabis to relieve pain, improve sleep and improve mood.

Methods

Adults with post-traumatic or postsurgical neuropathic pain were randomly assigned to receive cannabis at four potencies (0%, 2.5%, 6% and 9.4% tetrahydrocannabinol) over four 14-day periods in a crossover trial. Participants inhaled a single 25-mg dose through a pipe three times daily for the first five days in each cycle, followed by a nine-day washout period. Daily average pain intensity was measured using an 11-point numeric rating scale. We recorded effects on mood, sleep and quality of life, as well as adverse events.

Results

We recruited 23 participants (mean age 45.4 [standard deviation 12.3] years, 12 women [52%]), of whom 21 completed the trial. The average daily pain intensity, measured on the 11-point numeric rating scale, was lower on the prespecified primary contrast of 9.4% v. 0% tetrahydrocannabinol (5.4 v. 6.1, respectively; difference = 0.7, 95% confidence interval [CI] 0.02–1.4). Preparations with intermediate potency yielded intermediate but nonsignificant degrees of relief. Participants receiving 9.4% tetrahydrocannabinol reported improved ability to fall asleep (easier, p = 0.001; faster, p < 0.001; more drowsy, p = 0.003) and improved quality of sleep (less wakefulness, p = 0.01) relative to 0% tetrahydrocannabinol. We found no differences in mood or quality of life. The most common drug-related adverse events during the period when participants received 9.4% tetrahydrocannabinol were headache, dry eyes, burning sensation in areas of neuropathic pain, dizziness, numbness and cough.

Conclusion

A single inhalation of 25 mg of 9.4% tetrahydrocannabinol herbal cannabis three times daily for five days reduced the intensity of pain, improved sleep and was well tolerated. Further long-term safety and efficacy studies are indicated. (International Standard Randomised Controlled Trial Register no. ISRCTN68314063)Chronic neuropathic pain has a prevalence of 1%–2%,1 and treatment options are limited.2 Pharmacotherapy includes anticonvulsants, antidepressants, opioids and local anesthetics,3,4 but responses vary and side effects limit compliance.Cannabis sativa has been used to treat pain since the third millennium BC.5 An endogenous pain-processing system has been identified, mediated by endogenous cannabinoid ligands acting on specific cannabinoid receptors.6 These findings, coupled with anecdotal evidence of the analgesic effects of smoked cannabis,7 support a reconsideration of cannabinoid agents as analgesics.Oral cannabinoids such as tetrahydrocannabinol, cannabidiol and nabilone have, alone and in combination, shown efficacy in central8,9 and peripheral10 neuropathic pain, rheumatoid arthritis11 and fibromyalgia.12The analgesic effects of smoked cannabis remain controversial, although it is used by 10%–15% of patients with chronic noncancer pain13 and multiple sclerosis.14 Clinical trials are needed to evaluate these effects, given that the risks and benefits of inhaled cannabinoids may differ from oral agents. To date, three small clinical trials of the analgesic efficacy of smoked cannabis have been reported.1517 All studies were conducted in residential laboratories, and participants smoked multiple doses of the drug at each time point. No study adequately reported data related to adverse events.We conducted a clinical trial using a standardized single-dose delivery system to explore further the safety and efficacy of smoked cannabis in outpatients with chronic neuropathic pain.  相似文献   

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GC is commonly used for the analysis of cannabis samples, e.g. in forensic chemistry. However, as this method is based on heating of the sample, acidic forms of cannabinoids are decarboxylated into their neutral counterparts. Conversely, HPLC permits the determination of the original composition of plant cannabinoids by direct analysis. Several HPLC methods have been described in the literature, but most of them failed to separate efficiently all the cannabinoids or were not validated according to general guidelines. By use of an innovative methodology for modelling chromatographic responses, a simple and accurate HPLC/DAD method was developed for the quantification of major neutral and acidic cannabinoids present in cannabis plant material: Δ9-tetrahydrocannabinol (THC), THC acid (THCA), cannabidiol (CBD), CBD acid (CBDA), cannabigerol (CBG), CBG acid (CBGA) and cannabinol (CBN). Δ8-Tetrahydrocannabinol (Δ8-THC) was determined qualitatively. Following the practice of design of experiments, predictive multilinear models were developed and used in order to find optimal chromatographic analytical conditions. The method was validated following an approach using accuracy profiles based on β-expectation tolerance intervals for the total error measurement, and assessing the measurements uncertainty. This analytical method can be used for diverse applications, e.g. plant phenotype determination, evaluation of psychoactive potency and control of material quality.  相似文献   

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Interactions between cannabinoids and eicosanoids have been observed for the last several decades and account for a variety of cannabinoid actions. These were seen both in vitro and in vivo and may provide a molecular basis for these actions. Some of the topics included in this review are; effects on adenylate cyclase activity, alteration of behavioral responses, reduction of pain sensation, reduction and resolution of inflammation, hypotensive and vasorelaxant responses, anti-cancer and anti-metastatic activities, reduction of intraocular pressure and others. The most widely studied cannabinoids so far are tetrahydrocannabinol and cannabidiol. However, synthetic agents such as CP55,940, ajulemic acid, JWH-133 and WIN-55,212-2 were also investigated for interaction with eicosanoids. The endocannabinoids anandamide and 2-arachidonoylglycerol have been examined as well. Among the eicosanoids mediating cannabinoid actions are PGE2, 15-deoxy-Δ12, 14-prostaglandin-J2, lipoxin A4, lipoxin B4, and leukotriene B4. Enzyme activities involved include monoacylglycerylipase, adenylatecyclase, phospholipase A2, cyclooxygenases-1, 2 and 5, lipoxygenases-12 and 15. Receptors involved include CB1, CB2 and the EP3 and EP3 prostanoid receptors. While not all cannabinoid activities can be accounted for, many are best explained by eicosanoid participation. The recent surge in interest in “medical marijuana” makes understanding mechanisms of cannabinoid actions particularly important.  相似文献   

9.
Cannabis sativa L. has been utilized for treatment of pain and sleep disorders since ancient times. This review examines modern studies on effects of Delta9-tetrahydrocannabinol (THC) and cannabidiol (CBD) on sleep. It goes on to report new information on the effects on sleep in the context of medical treatment of neuropathic pain and symptoms of multiple sclerosis, employing standardized oromucosal cannabis-based medicines containing primarily THC, CBD, or a 1 : 1 combination of the two (Sativex). Sleep-laboratory results indicate a mild activating effect of CBD, and slight residual sedation with THC-predominant extracts. Experience to date with Sativex in numerous Phase I-III studies in 2000 subjects with 1000 patient years of exposure demonstrate marked improvement in subjective sleep parameters in patients with a wide variety of pain conditions including multiple sclerosis, peripheral neuropathic pain, intractable cancer pain, and rheumatoid arthritis, with an acceptable adverse event profile. No tolerance to the benefit of Sativex on pain or sleep, nor need for dosage increases have been noted in safety extension studies of up to four years, wherein 40-50% of subjects attained good or very good sleep quality, a key source of disability in chronic pain syndromes that may contribute to patients' quality of life.  相似文献   

10.
ObjectiveTo quantify the antiemetic efficacy and adverse effects of cannabis used for sickness induced by chemotherapy.DesignSystematic review.Studies30 randomised comparisons of cannabis with placebo or antiemetics from which dichotomous data on efficacy and harm were available (1366 patients). Oral nabilone, oral dronabinol (tetrahydrocannabinol), and intramuscular levonantradol were tested. No cannabis was smoked. Follow up lasted 24 hours.ResultsCannabinoids were more effective antiemetics than prochlorperazine, metoclopramide, chlorpromazine, thiethylperazine, haloperidol, domperidone, or alizapride: relative risk 1.38 (95% confidence interval 1.18 to 1.62), number needed to treat 6 for complete control of nausea; 1.28 (1.08 to 1.51), NNT 8 for complete control of vomiting. Cannabinoids were not more effective in patients receiving very low or very high emetogenic chemotherapy. In crossover trials, patients preferred cannabinoids for future chemotherapy cycles: 2.39 (2.05 to 2.78), NNT 3. Some potentially beneficial side effects occurred more often with cannabinoids: “high” 10.6 (6.86 to 16.5), NNT 3; sedation or drowsiness 1.66 (1.46 to 1.89), NNT 5; euphoria 12.5 (3.00 to 52.1), NNT 7. Harmful side effects also occurred more often with cannabinoids: dizziness 2.97 (2.31 to 3.83), NNT 3; dysphoria or depression 8.06 (3.38 to 19.2), NNT 8; hallucinations 6.10 (2.41 to 15.4), NNT 17; paranoia 8.58 (6.38 to 11.5), NNT 20; and arterial hypotension 2.23 (1.75 to 2.83), NNT 7. Patients given cannabinoids were more likely to withdraw due to side effects 4.67 (3.07 to 7.09), NNT 11.ConclusionsIn selected patients, the cannabinoids tested in these trials may be useful as mood enhancing adjuvants for controlling chemotherapy related sickness. Potentially serious adverse effects, even when taken short term orally or intramuscularly, are likely to limit their widespread use.

What is already known on this topic

Requests have been made for legalisation of cannabis (marijuana) for medical useLong term smoking of cannabis can have physical and neuropsychiatric adverse effectsCannabis may be useful in the control of chemotherapy related sickness

What this study adds

Oral nabilone and dronabinol and intramuscular levonantradol are superior to conventional antiemetics (such as prochlorperazine or metoclopramide) in chemotherapySide effects are common with cannabinoids, and although some may be potentially beneficial (euphoria, “high,” sedation), others are harmful (dysphoria, depression, hallucinations)Many patients have a strong preference for cannabinoids  相似文献   

11.
The marijuana plant (Cannabis sativa) and preparations derived from it have been used for medicinal purposes for thousands of years. It is likely that the therapeutic benefits of smoked marijuana are due to some combination of its more than 60 cannabinoids and 200-250 non-cannabinoid constituents. Several marijuana constituents, the carboxylic acid metabolites of tetrahydrocannabinol, and synthetic analogs are free of cannabimimetic central nervous system activity, do not produce behavioral changes in humans, and are effective antiinflammatory and analgesic agents. One cannabinoid acid in particular, ajulemic acid, has been studied extensively in in vitro systems and animal models of inflammation and immune responses. This commentary reviews a portion of the work done by investigators interested in separating the medicinal properties of marijuana from its psychoactive effects. Understanding the mechanisms of the therapeutic effects of nonpsychoactive cannabinoids should lead to development of safe effective treatment for several diseases, and may render moot the debate about "medical marijuana".  相似文献   

12.
Cannabidiol (CBD) is a major, biologically active, but psycho-inactive component of cannabis. In this cell culture-based report, CBD is shown to displace the agonist, [3H]8-OH-DPAT from the cloned human 5-HT1a receptor in a concentration-dependent manner. In contrast, the major psychoactive component of cannabis, tetrahydrocannabinol (THC) does not displace agonist from the receptor in the same micromolar concentration range. In signal transduction studies, CBD acts as an agonist at the human 5-HT1a receptor as demonstrated in two related approaches. First, CBD increases [35S]GTPγS binding in this G protein coupled receptor system, as does the known agonist serotonin. Second, in this GPCR system, that is negatively coupled to cAMP production, both CBD and 5-HT decrease cAMP concentration at similar apparent levels of receptor occupancy, based upon displacement data. Preliminary comparative data is also presented from the cloned rat 5-HT2a receptor suggesting that CBD is active, but less so, relative to the human 5-HT1a receptor, in binding analyses. Overall, these studies demonstrate that CBD is a modest affinity agonist at the human 5-HT1a receptor. Additional work is required to compare CBD’s potential at other serotonin receptors and in other species. Finally, the results indicate that cannabidiol may have interesting and useful potential beyond the realm of cannabinoid receptors.  相似文献   

13.
Cannabinoids have been utilized for recreational and therapeutic purposes for over 4,000 years. As the primary ingredient in exogenous cannabinoids, Cannabidiol (CBD) has drawn a lot of interest from researchers due to its negligible psychotropic side effects and potential tumor-suppressing properties. However, the obscure mechanisms that underlie them remain a mystery. Complex biological mechanisms are involved in the progression of cancer, and malignancies have a variety of acquired biological capabilities, including sustained proliferation, death evasion, neovascularization, tissue invasion and metastasis, immune escape, metabolic reprogramming, induction of tumor-associated inflammation, cancerous stemness and genomic instability. Nowadays, the role of CBD hidden in these hallmarks is gradually revealed. Nevertheless, flaws or inconsistencies in the recent studies addressing the anti-cancer effects of CBD still exist. The purpose of this review is to evaluate the potential mechanisms underlying the role of CBD in a range of tumor-acquired biological capabilities. We propose potential drugs that may have a synergistic effect with CBD and provide optional directions for future research.  相似文献   

14.
Marijuana has been shown to lower intraocular pressure (IOP) but with limited duration of action and numerous adverse effects. Use of marijuana to lower IOP as a means of glaucoma treatment would require frequent use throughout the day, leading to significant adverse effects, possible progression toward Cannabis Use Disorder (CUD), and/or withdrawal symptoms. The treatment of glaucoma based on the cannabis plant or drugs based on the cannabinoid molecule should be considered carefully before being prescribed. Considerations should include the adverse physical and psychological adverse effects, including substance abuse. Currently, the deleterious effects of marijuana outweigh the benefits of its IOP-lowering capacity in most glaucoma patients. Under extremely rare circumstances, a few categories of glaucoma patients may be potential candidates for treatment with medical marijuana. Further studies on alternate routes and more focused means of cannabinoid molecule delivery to the eye for glaucoma treatment are needed.  相似文献   

15.
Introduction – Cannabis and cannabinoid based medicines are currently under serious investigation for legitimate development as medicinal agents, necessitating new low‐cost, high‐throughput analytical methods for quality control. Objective – The goal of this study was to develop and validate, according to ICH guidelines, a simple rapid HPTLC method for the quantification of Δ9‐tetrahydrocannabinol (Δ9‐THC) and qualitative analysis of other main neutral cannabinoids found in cannabis. Methodology – The method was developed and validated with the use of pure cannabinoid reference standards and two medicinal cannabis cultivars. Accuracy was determined by comparing results obtained from the HTPLC method with those obtained from a validated HPLC method. Results – Δ9‐THC gives linear calibration curves in the range of 50–500 ng at 206 nm with a linear regression of y = 11.858x + 125.99 and r2 = 0.9968. Conclusion – Results have shown that the HPTLC method is reproducible and accurate for the quantification of Δ9‐THC in cannabis. The method is also useful for the qualitative screening of the main neutral cannabinoids found in cannabis cultivars. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

16.
Neuropathic pain refers to chronic pain that results from injury to the nervous system. The mechanisms involved in neuropathic pain are complex and involve both peripheral and central phenomena. Although numerous pharmacological agents are available for the treatment of neuropathic pain, definitive drug therapy has remained elusive. Recent drug discovery efforts have identified an original neurobiological approach to the pathophysiology of neuropathic pain. The development of innovative pharmacological strategies has led to the identification of new promising pharmacological targets, including glutamate antagonists, microglia inhibitors and, interestingly, endogenous ligands of cannabinoids and the transient receptor potential vanilloid type 1 (TRPV1). Endocannabinoids (ECs), endovanilloids and the enzymes that regulate their metabolism represent promising pharmacological targets for the development of a successful pain treatment. This review is an update of the relationship between cannabinoid receptors (CB1) and TRPV1 channels and their possible implications for neuropathic pain. The data are focused on endogenous spinal mechanisms of pain control by anandamide, and the current and emerging pharmacotherapeutic approaches that benefit from the pharmacological modulation of spinal EC and/or endovanilloid systems under chronic pain conditions will be discussed.  相似文献   

17.
Marihuana and hashish are the most widely used illicit drugs. They are derived from the hemp plant, Cannabis sativa. Among the diverse chemicals in the plant, more than 20 so-called cannabinoids have been isolated and their chemical structures elucidated (1). In 1965, Mechoulam and coworkers (2,3) isolated △9- tetrahydrocannabinol (△9-THC) from cannabis extract and demonstrated that it was responsible for the psychopharmacologic effects of cannabis in animals. Later, Isbell (4) and Hollister et al. (5) confirmed these findings in man. This paper reviews the physiologic disposition of △9-THC in man; the disposition of △9-THC in animals has been reviewed elsewhere (6, 7, 8).  相似文献   

18.
19.
Cannabinoids delta 1-tetrahydrocannabinol, cannabinol, cannabidiol and cannabigerol have been shown to affect directly the activity of phospholipase A2 in a cell-free assay. The compounds produced a biphasic activation of the enzyme, with EC50 values in the range 6.0-20.0 X 10(-6) M and IC50 values in the range 50.0-150.0 X 10(-6) M. These results correlated well with the relative potencies reported for the stimulation of prostaglandin release from human synovial cells in vitro, confirming that activation of phospholipase A2 is the predominant action of cannabinoids on arachidonate metabolism in tissue culture. However, since delta 1-tetrahydrocannabinol is unique among these compounds in possessing cataleptic activity, it is unlikely that phospholipase A2 is the major receptor mediating the psychotropic effects of cannabis.  相似文献   

20.
Recent analysis of the cannabinoid content of cannabis plants suggests a shift towards use of high potency plant material with high levels of Δ9-tetrahydrocannabinol (THC) and low levels of other phytocannabinoids, particularly cannabidiol (CBD). Use of this type of cannabis is thought by some to predispose to greater adverse outcomes on mental health and fewer therapeutic benefits. Australia has one of the highest per capita rates of cannabis use in the world yet there has been no previous systematic analysis of the cannabis being used. In the present study we examined the cannabinoid content of 206 cannabis samples that had been confiscated by police from recreational users holding 15 g of cannabis or less, under the New South Wales “Cannabis Cautioning” scheme. A further 26 “Known Provenance” samples were analysed that had been seized by police from larger indoor or outdoor cultivation sites rather than from street level users. An HPLC method was used to determine the content of 9 cannabinoids: THC, CBD, cannabigerol (CBG), and their plant-based carboxylic acid precursors THC-A, CBD-A and CBG-A, as well as cannabichromene (CBC), cannabinol (CBN) and tetrahydrocannabivarin (THC-V). The “Cannabis Cautioning” samples showed high mean THC content (THC+THC-A = 14.88%) and low mean CBD content (CBD+CBD-A = 0.14%). A modest level of CBG was detected (CBG+CBG-A = 1.18%) and very low levels of CBC, CBN and THC-V (<0.1%). “Known Provenance” samples showed no significant differences in THC content between those seized from indoor versus outdoor cultivation sites. The present analysis echoes trends reported in other countries towards the use of high potency cannabis with very low CBD content. The implications for public health outcomes and harm reduction strategies are discussed.  相似文献   

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