Low-dose vaporized cannabis significantly improves neuropathic pain

A Cost-Effectiveness Model for Adjunctive Smoked Cannabis in the Treatment of Chronic Neuropathic Pain

Background: A recent meta-analysis affirmed the benefit of medicinal cannabis for chronic neuropathic pain, a disabling and difficult-to-treat condition. As medicinal cannabis use is becoming increasingly prevalent among Americans, an exploration of its economic feasibility is warranted. We present this cost-effectiveness analysis of adjunctive cannabis pharmacotherapy for chronic peripheral neuropathy.

Materials and Methods: A published Markov model comparing conventional therapies for painful diabetic neuropathy was modified to include arms for augmenting first-line, second-line (if first-line failed), or third-line (if first- and second-line failed) therapies with smoked cannabis. Microsimulation of 1,000,000 patients compared the cost (2017 U.S. dollars) and effectiveness (quality-adjusted life years [QALYs]) of usual care with and without adjunctive cannabis using a composite of third-party and out-of-pocket costs. Model efficacy inputs for cannabis were adapted from clinical trial data. Adverse event rates were derived from a prospective study of cannabis for chronic noncancer pain and applied to probability inputs for conventional therapies. Cannabis cost was derived from retail market pricing. Parameter uncertainty was addressed with one-way and probabilistic sensitivity analysis.

Results: Adding cannabis to first-line therapy was incrementally less effective and costlier than adding cannabis to second-line and third-line therapies. Third-line adjunctive cannabis was subject to extended dominance, that is, the second-line strategy was more effective with a more favorable incremental cost-effectiveness ratio of $48,594 per QALY gained, and therefore, third-line adjunctive cannabis was not as cost-effective. At a modest willingness-to-pay threshold of $100,000/QALY gained, second-line adjunctive cannabis was the strategy most likely to be cost-effective.

Conclusion: As recently proposed willingness-to-pay thresholds for the United States health marketplace range from $110,000 to $300,000 per QALY, cannabis appears cost-effective when augmenting second-line treatment for painful neuropathy. Further research is warranted to explore the long-term benefit of smoked cannabis and standardization of its dosing for chronic neuropathic pain.

Perspectives on cannabis as a substitute for opioid analgesics

With the opioid epidemic reaching new heights in the USA, it has become critical to find suitable alternatives to opioids. Cannabis, an antinociceptive, is a strong contender to help patients reduce their opioid usage. A growing literature has been examining the complex effects cannabis has on pain relief and on opioid usage; whether it is a substitute for opioids or increases their use. This review explores the studies that compare cannabis-opioid interactions and presents some challenges of cannabis research and usage. The practical clinical pharmacology of cannabis as an analgesic, including the route of administration, safety and pharmacokinetics, are discussed to address the concerns, as well as possible solutions, of cannabis as a pain reliever.

Some Prospective Alternatives for Treating Pain: The Endocannabinoid System and Its Putative Receptors GPR18 and GPR55

Background: Marijuana extracts (cannabinoids) have been used for several millennia for pain treatment. Regarding the site of action, cannabinoids are highly promiscuous molecules, but only two cannabinoid receptors (CB₁ and CB₂) have been deeply studied and classified. Thus, therapeutic actions, side effects and pharmacological targets for cannabinoids have been explained based on the pharmacology of cannabinoid CB₁/CB₂ receptors. However, the accumulation of confusing and sometimes contradictory results suggests the existence of other cannabinoid receptors. Different orphan proteins (e.g., GPR18, GPR55, GPR119, etc.) have been proposed as putative cannabinoid receptors. According to their expression, GPR18 and GPR55 could be involved in sensory transmission and pain integration.

Methods: This article reviews select relevant information about the potential role of GPR18 and GPR55 in the pathophysiology of pain.

Results: This work summarized novel data supporting that, besides cannabinoid CB₁ and CB₂ receptors, GPR18 and GPR55 may be useful for pain treatment.

Conclusion: There is evidence to support an antinociceptive role for GPR18 and GPR55.

Overlaps in pharmacology for the treatment of chronic pain and mental health disorders

There is significant overlap in the pharmacological management of pain and psychological disorders. Appropriate treatment of patients' comorbid psychological disorders, including sleep disturbances often leads to an improvement in reported pain intensity. The three first line agents for neuropathic pain include tricyclic antidepressants and serotonin norepinephrine reuptake inhibitors which are medications originally developed as antidepressants. The other first line medication for chronic neuropathic pain are anticonvulsant medications initially brought to the market-place for the treatment of epilepsy and are also now being used for the treatment of anxiety disorders and substance withdrawal symptoms. The efficacy of opioids for chronic pain is contentious, but it is agreed that the patients at highest risk for opioid misuse and addiction are patients with underlying psychological disorders who use opioids for their euphoric effects. Similarly, benzodiazepines may present a problem in patients with chronic pain, as up to one third of patients with pain are concomitantly prescribed benzodiazepines, and when combined with other sedating analgesic medications they put patients at increased risk for adverse events and polysubstance misuse. Finally, there is growing evidence for the efficacy of cannabis for treating neuropathic pain, but the consumption of cannabis has been associated with increased risk of psychosis in adolescents, and may be associated with an increased risk for developing bipolar disorder and anxiety disorders. The use of cannabis is associated with an increased risk of substance misuse in both adolescents and adults. In this narrative review, we examine the evidence for the use of several medications used for the treatment of both pain and psychological disorders, and their proposed mechanisms of action, in addition to special concerns for patients with comorbid pain and psychological disorders.

Cannabinoids and Pain: New Insights From Old Molecules

Cannabis has been used for medicinal purposes for thousands of years. The prohibition of cannabis in the middle of the 20th century has arrested cannabis research. In recent years there is a growing debate about the use of cannabis for medical purposes. The term ‘medical cannabis’ refers to physician-recommended use of the cannabis plant and its components, called cannabinoids, to treat disease or improve symptoms. Chronic pain is the most commonly cited reason for using medical cannabis. Cannabinoids act via cannabinoid receptors, but they also affect the activities of many other receptors, ion channels and enzymes. Preclinical studies in animals using both pharmacological and genetic approaches have increased our understanding of the mechanisms of cannabinoid-induced analgesia and provided therapeutical strategies for treating pain in humans. The mechanisms of the analgesic effect of cannabinoids include inhibition of the release of neurotransmitters and neuropeptides from presynaptic nerve endings, modulation of postsynaptic neuron excitability, activation of descending inhibitory pain pathways, and reduction of neural inflammation. Recent meta-analyses of clinical trials that have examined the use of medical cannabis in chronic pain present a moderate amount of evidence that cannabis/cannabinoids exhibit analgesic activity, especially in neuropathic pain. The main limitations of these studies are short treatment duration, small numbers of patients, heterogeneous patient populations, examination of different cannabinoids, different doses, the use of different efficacy endpoints, as well as modest observable effects. Adverse effects in the short-term medical use of cannabis are generally mild to moderate, well tolerated and transient. However, there are scant data regarding the long-term safety of medical cannabis use. Larger well-designed studies of longer duration are mandatory to determine the long-term efficacy and long-term safety of cannabis/cannabinoids and to provide definitive answers to physicians and patients regarding the risk and benefits of its use in the treatment of pain. In conclusion, the evidence from current research supports the use of medical cannabis in the treatment of chronic pain in adults. Careful follow-up and monitoring of patients using cannabis/cannabinoids are mandatory.

Medical cannabis legalization and opioid prescriptions: evidence on US Medicaid enrollees during 1993-2014

BACKGROUND AND AIMS

While the United States has been experiencing an opioid epidemic, 29 states and Washington DC have legalized cannabis for medical use. This study examined whether state-wide medical cannabis legalization was associated with reduction in opioids received by Medicaid enrollees.

DESIGN

Secondary data analysis of state-level opioid prescription records from 1993-2014 Medicaid State Drug Utilization Data. Linear time-series regressions assessed the associations between medical cannabis legalization and opioid prescriptions, controlling for state-level time-varying policy covariates (such as prescription drug monitoring programs) and socio-economic covariates (such as income).

SETTING

United States.

PARTICIPANTS

Drug prescription records for patients enrolled in fee-for-service Medicaid programs that primarily provide health-care coverage to low-income and disabled people.

MEASUREMENTS

The primary outcomes were population-adjusted number, dosage and Medicaid spending on opioid prescriptions. Outcomes for Schedule II opioids (e.g. hydrocodone, oxycodone) and Schedule III opioids (e.g. codeine) were analyzed separately. The primary policy variable of interest was the implementation of state-wide medical cannabis legalization.

FINDINGS

For Schedule III opioid prescriptions, medical cannabis legalization was associated with a 29.6% (P = 0.03) reduction in number of prescriptions, 29.9% (P = 0.02) reduction in dosage and 28.8% (P = 0.04) reduction in related Medicaid spending. No evidence was found to support the associations between medical cannabis legalization and Schedule II opioid prescriptions. Permitting medical cannabis dispensaries was not associated with Schedule II or Schedule III opioid prescriptions after controlling for medical cannabis legalization. It was estimated that, if all the states had legalized medical cannabis by 2014, Medicaid annual spending on opioid prescriptions would be reduced by 17.8 million dollars.

CONCLUSION

State-wide medical cannabis legalization appears to have been associated with reductions in both prescriptions and dosages of Schedule III (but not Schedule II) opioids received by Medicaid enrollees in the United States.

The Risks and Benefits of Cannabis in the Dermatology Clinic

Cannabis ( Cannabis sativa/indica), also known as marijuana, has been used for medicinal and recreational purposes for millennia. There has been a recent trend to legalize the use of cannabis, as illustrated by the recent legalization votes in numerous states in the United States and legislation in Canada to allow recreational cannabis use. With this increasing consumption of cannabis, dermatologists will see increased pressure to prescribe cannabis and will see the side effects of cannabis use with greater frequency. There are several approved medical indications for cannabis use, including psoriasis, lupus, nail-patella syndrome, and severe pain. In addition, very preliminary studies have suggested cannabis and its derivatives might have use in acne, dermatitis, pruritus, wound healing, and skin cancer. Further well-controlled studies are required to explore these potential uses. Conversely, the side effects of cannabis use are relatively well documented, and dermatologists should be aware of these presentations. Side effects of cannabis use include cannabis allergy manifesting as urticaria and pruritus, cannabis arteritis presenting with necrosis and ulcers, and oral cancers from cannabis smoke. In this review, we summarize some of the studies and reports regarding the medicinal uses of cannabis in the dermatology clinic and some of the side effects that might present more often to dermatologists as the use of cannabis increases.

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.

Plant-Based Cannabinoids for the Treatment of Chronic Neuropathic Pain

Chronic neuropathic pain is a prevalent condition that places a heavy burden on individuals and the healthcare system. Current medications have limitations and new approaches are needed, particularly given the current opioid crisis. There is some clinical evidence that the plant Cannabis sativa produces relief from neuropathic pain. However, current meta-analyses suggest that this efficacy is limited and there are problems with side effects. Most of this clinical research has examined whole cannabis, the psychoactive phytocannabinoid 9-tetrahydrocannabinol (THC), and nabiximols, which are a mixture of THC and the non-psychoactive phytocannabinoid cannabidiol. In the past, there has been little evidence based, preclinical animal research to guide clinical studies on phytocannabinoids. Recent animal studies indicate that while THC and high dose nabiximols are effective in animal neuropathic pain models, significant pain relief is only achieved at doses that produce substantial side effects. By contrast, cannabidiol and low dose nabiximols have moderate pain relieving efficacy, but are devoid of cannabinoid-like side effects. This animal data suggests that cannabidiol and low dose nabiximols warrant consideration for clinical studies, at least as adjuvants to current drugs. Preclinical research is also required to identify other phytocannabinoids that have therapeutic potential.

Structure-Activity Relationship of Cannabis Derived Compounds for the Treatment of Neuronal Activity-Related Diseases

Cannabis sativa active compounds are extensively studied for their therapeutic effects, beyond the well-known psychotropic activity. C. Sativa is used to treat different medical indications, such as multiple sclerosis, spasticity, epilepsy, ulcerative colitis and pain. Simultaneously, basic research is discovering new constituents of cannabis-derived compounds and their receptors capable of neuroprotection and neuronal activity modulation. The function of the various phytochemicals in different therapeutic processes is not fully understood, but their significant role is starting to emerge and be appreciated. In this review, we will consider the structure-activity relationship (SAR) of cannabinoid compounds able to bind to cannabinoid receptors and act as therapeutic agents in neuronal diseases, e.g., Parkinson’s disease.

Cannabinoids for Treatment of MS Symptoms: State of the Evidence

PURPOSE OF REVIEW

Cannabis and cannabinoids have been used medically and recreationally for thousands of years and recently there has been a growing body of research in this area. With increased access now that medical marijuana is available in many jurisdictions, patients and providers want to know more about the evidence for benefits and risks of cannabinoid use. This paper provides an overview of the available cannabinoid-based formulations, a summary of the highest quality evidence for the use of cannabinoids for treating spasticity and pain associated with multiple sclerosis (MS), and a discussion of possible dosing regimens based on information from these studies.

RECENT FINDINGS

Two recent high-quality systematic reviews concluded that the only strong evidence for medical marijuana in neurological disorders was for reducing the symptoms of patient-reported spasticity and central pain in MS and that the only complementary and alternative medicine (CAM) intervention in MS with strong supportive evidence was cannabinoids. Based on this review, they concluded that nabiximols (Sativex oral spray), oral cannabis extract (OCE), and synthetic tetrahydrocannabinol (THC) are probably effective at reducing patient-reported symptoms of spasticity in people with MS, but OCE and synthetic THC were not found to be effective for reducing physician-administered measures of spasticity. In addition, nabiximols, OCE, and synthetic THC are probably effective at reducing MS-related pain. Cannabinoids were generally well-tolerated. However, cannabis use has been associated with an increased risk of psychosis and schizophrenia in at-risk individuals, there is growing evidence that cannabis can increase the risk for cardiovascular diseases, including myocardial infarction (MI), hypertension, heart failure, and stroke, and a recently recognized adverse effect of cannabis is cannabinoid hyperemesis syndrome. The medical use of cannabinoids remains controversial. While cannabinoids have been studied for a variety of neurologic disorders, there is strongest evidence to indicate benefits in treatment of spasticity and neuropathic pain in multiple sclerosis. Although the best dose for an individual remains uncertain, most participants in the studies discussed in this paper used between 20 and 40 mg of THC a day in divided doses. Adverse events in studies were generally more common in the groups using cannabinoid products but serious adverse events were rare and cannabis products were generally well-tolerated. Cannabis use does appear to be associated with increased risk of certain adverse events, including psychosis, cardiovascular diseases, and cannabinoid hyperemesis syndrome.

The grass is not always greener: a multi-institutional pilot study of marijuana use and acute pain management following traumatic injury

Background

Widespread legislative efforts to legalize marijuana have increased the prevalence of marijuana use and abuse. The effects of marijuana on pain tolerance and analgesic pain management in the acute pain setting have not been reported. Although marijuana has been shown to have antinociceptive effects and is approved for medical use to treat chronic pain, anecdotal evidence suggests marijuana users admitted with traumatic injuries experience poorer pain control than patients who do not use marijuana. We hypothesized that marijuana users would report higher pain scores and require more opioid analgesia following traumatic injury.

Methods

This retrospective pilot study included all patients involved in motor vehicle crashes, consecutively admitted to four trauma centers from 1/1/2016–4/30/2016. Marijuana status was examined as non-use and use, and was further categorized as chronic and episodic use. We performed a repeated measures mixed model to examine the association between marijuana use and a) average daily opioid consumption and b) average daily pain scores (scale 0–10). Opioid analgesics were converted to be equianalgesic to 1 mg IV hydromorphone.

Results

Marijuana use was reported in 21% (54/261), of which 30% reported chronic use (16/54). Marijuana use was reported more frequently in Colorado hospitals (23–29%) compared to the hospital in Texas (6%). Drug use with other prescription/street drugs was reported in 9% of patients. Other drug use was a significant effect modifier and results were presented after stratification by drug use. After adjustment, marijuana users who did not use other drugs consumed significantly more opioids (7.6 mg vs. 5.6 mg, p <  0.001) and reported higher pain scores (4.9 vs. 4.2, p <  0.001) than non-marijuana users. Conversely, in patients who used other drugs, there were no differences in opioid consumption (5.6 mg vs. 6.1 mg, p = 0.70) or pain scores (5.3 vs. 6.0, p = 0.07) with marijuana use compared to non-use, after adjustment. Chronic marijuana use was associated with significantly higher opioid consumption compared to episodic marijuana use in concomitant drug users (11.3 mg vs. 4.4 mg, p = 0.008) but was similar in non-drug users (p = 0.41).

Conclusion

These preliminary data suggest that marijuana use, especially chronic use, may affect pain response to injury by requiring greater use of opioid analgesia. These results were less pronounced in patients who used other drugs.

Therapeutic potential of medicinal marijuana: an educational primer for health care professionals

With the proposed Canadian July 2018 legalization of marijuana through the Cannabis Act, a thorough critical analysis of the current trials on the efficacy of medicinal marijuana (MM) as a treatment option is necessary. This review is particularly important for primary care physicians whose patients may be interested in using MM as an alternative therapy. In response to increased interest in MM, Health Canada released a document in 2013 for general practitioners (GPs) as an educational tool on the efficacy of MM in treating some chronic and acute conditions. Although additional studies have filled in some of the gaps since the release of the Health Canada document, conflicting and inconclusive results continue to pose a challenge for physicians. This review aims to supplement the Health Canada document by providing physicians with a critical yet concise update on the recent advancements made regarding the efficacy of MM as a potential therapeutic option. An update to the literature of 2013 is important given the upcoming changes in legislation on the use of marijuana. Also, we briefly highlight the current recommendations provided by Canadian medical colleges on the parameters that need to be considered prior to authorizing MM use, routes of administration as well as a general overview of the endocannabinoid system as it pertains to cannabis. Lastly, we outline the appropriate medical conditions for which the authorization of MM may present as a practical alternative option in improving patient outcomes as well as individual considerations of which GPs should be mindful. The purpose of this paper is to offer physicians an educational tool that provides a necessary, evidence-based analysis of the therapeutic potential of MM and to ensure physicians are making decisions on the therapeutic use of MM in good faith.

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.

Cannabis for Chronic Pain: Challenges and Considerations

The National Academies of Sciences, Engineering, and Medicine has found substantial evidence that cannabis (plant) is effective for the treatment of chronic pain in adults, and moderate evidence that oromucosal cannabinoids (extracts, especially nabiximols) improve short-term sleep disturbances in chronic pain. The paradoxical superiority of the cannabis plant over cannabinoid molecules represents a challenge for the medical community and the established processes that define modern pharmacy. The expanding and variable legalization of cannabis in multiple states nationwide represents an additional challenge for patients and the medical community because recreational and medicinal cannabis are irresponsibly overlapped. Cannabis designed for recreational use (containing high levels of active ingredients) is increasingly available to patients with chronic pain who do not find relief with current pharmacologic entities, which exposes patients to potential harm. This article analyzes the available scientific evidence to address controversial questions that the current state of cannabis poses for health care professionals and chronic pain patients and sets the basis for a more open discussion about the role of cannabis in modern medicine for pain management. A critical discussion on these points, the legal status of cannabis, and considerations for health care providers is presented.

Medical Oncologists' Beliefs, Practices, and Knowledge Regarding Marijuana Used Therapeutically: A Nationally Representative Survey Study

Background Although almost every state medical marijuana (MM) law identifies cancer as a qualifying condition, little research supports MM's use in oncology. We hypothesized that the discrepancy between these laws and the scientific evidence base poses clinical challenges for oncologists. Oncologists' beliefs, knowledge, and practices regarding MM were examined in this study. Methods In November 2016, we mailed a survey on MM to a nationally-representative, random sample of 400 medical oncologists. Main outcome measures included whether oncologists reported discussing MM with patients, recommended MM clinically in the past year, or felt sufficiently informed to make such recommendations. The survey also queried oncologists' views on MM's comparative effectiveness for several conditions (including its use as an adjunct to standard pain management strategies) and its risks compared with prescription opioids. Bivariate and multivariate analyses were performed using standard statistical techniques. Results The overall response rate was 63%. Whereas only 30% of oncologists felt sufficiently informed to make recommendations regarding MM, 80% conducted discussions about MM with patients, and 46% recommended MM clinically. Sixty-seven percent viewed it as a helpful adjunct to standard pain management strategies, and 65% thought MM is equally or more effective than standard treatments for anorexia and cachexia. Conclusion Our findings identify a concerning discrepancy between oncologists' self-reported knowledge base and their beliefs and practices regarding MM. Although 70% of oncologists do not feel equipped to make clinical recommendations regarding MM, the vast majority conduct discussions with patients about MM and nearly one-half do, in fact, recommend it clinically. A majority believes MM is useful for certain indications. These findings are clinically important and suggest critical gaps in research, medical education, and policy regarding MM.

Preliminary evaluation of the efficacy, safety, and costs associated with the treatment of chronic pain with medical cannabis

Introduction:

Medical cannabis (MC) is commonly claimed to be an effective treatment for chronic or refractory pain. With interest in MC in the United States growing, as evidenced by the 29 states and 3 US districts that now have public MC programs, the need for clinical evidence supporting this claim has never been greater.

Methods:

This was a retrospective, mirror-image study that investigated MC's effectiveness in patients suffering from chronic pain associated with qualifying conditions for MC in New York State. The primary outcome was to compare European Quality of Life 5 Dimension Questionnaire (EQ-5D) and Pain Quality Assessment Scale (PQAS) scores at baseline and 3 months post-therapy. The secondary outcomes included comparisons of monthly analgesic prescription costs and opioid consumption pre- and post-therapy. Tolerability was assessed by side effect incidence.

Results:

This investigation included 29 subjects. Quality of life and pain improved, measured by change in EQ-5D (Pre 36 – Post 64, P < .0001) and change in PQAS paroxysmal (Pre 6.76 – Post 2.04, P < .0001), surface (Pre 4.20 – Post 1.30, P < .0001), deep (Pre 5.87 – Post 2.03, P < .0001), unpleasant (Pre “miserable” – Post “annoying”, P < .0001). Adverse effects were reported in 10% of subjects.

Discussion:

After 3 months treatment, MC improved quality of life, reduced pain and opioid use, and lead to cost savings. Large randomized clinical trials are warranted to further evaluate the role of MC in the treatment of chronic pain.

Evidence for the use of "medical marijuana" in psychiatric and neurologic disorders

Introduction

Cannabis is listed as a Schedule I substance under the Controlled Substances Act of 1970, meaning the US federal government defines it as an illegal drug that has high potential for abuse and no established medical use; however, half of the states in the nation have enacted "medical marijuana" (MM) laws. Clinicians must be aware of the evidence for and against the use of MM in their patients who may consider using this substance.

Methods

A PubMed database search was performed using the text string: "Cannabis"[Mesh] OR "Marijuana Abuse"[Mesh] OR "Medical Marijuana"[Mesh] OR "Marijuana Smoking"[Mesh] OR "cannabi*" OR "tetrahydrocannabinol." The search was further limited to randomized clinical trial publications in English on human subjects to identify articles regarding the therapeutic use of phytocannabinoids for psychiatric and neurologic disorders. Commercially available products (ie, dronabinol, nabilone, nabiximols) and synthetic cannabinoids were excluded from the review.

Results

Publications were identified that included patients with dementia, multiple sclerosis, Parkinson disease, Huntington disease, schizophrenia, social anxiety disorder, depression, tobacco use disorder, and neuropathic pain.

Discussion

There is great variety concerning which medical conditions are approved for treatment with MM for either palliative or therapeutic benefit, depending on the state law. It is important to keep an evidence-based approach in mind, even with substances considered to be illegal under US federal law. Clinicians must weigh risks and benefits of the use of MM in their patients and should ensure that patients have tried other treatment modalities with higher levels of evidence for use when available and appropriate.

Cannabis-based medicines for chronic neuropathic pain in adults

BACKGROUND

This review is one of a series on drugs used to treat chronic neuropathic pain. Estimates of the population prevalence of chronic pain with neuropathic components range between 6% and 10%. Current pharmacological treatment options for neuropathic pain afford substantial benefit for only a few people, often with adverse effects that outweigh the benefits. There is a need to explore other treatment options, with different mechanisms of action for treatment of conditions with chronic neuropathic pain. Cannabis has been used for millennia to reduce pain. Herbal cannabis is currently strongly promoted by some patients and their advocates to treat any type of chronic pain.

OBJECTIVES

To assess the efficacy, tolerability, and safety of cannabis-based medicines (herbal, plant-derived, synthetic) compared to placebo or conventional drugs for conditions with chronic neuropathic pain in adults.

SEARCH METHODS

In November 2017 we searched CENTRAL, MEDLINE, Embase, and two trials registries for published and ongoing trials, and examined the reference lists of reviewed articles.

SELECTION CRITERIA

We selected randomised, double-blind controlled trials of medical cannabis, plant-derived and synthetic cannabis-based medicines against placebo or any other active treatment of conditions with chronic neuropathic pain in adults, with a treatment duration of at least two weeks and at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data of study characteristics and outcomes of efficacy, tolerability and safety, examined issues of study quality, and assessed risk of bias. We resolved discrepancies by discussion. For efficacy, we calculated the number needed to treat for an additional beneficial outcome (NNTB) for pain relief of 30% and 50% or greater, patient's global impression to be much or very much improved, dropout rates due to lack of efficacy, and the standardised mean differences for pain intensity, sleep problems, health-related quality of life (HRQoL), and psychological distress. For tolerability, we calculated number needed to treat for an additional harmful outcome (NNTH) for withdrawal due to adverse events and specific adverse events, nervous system disorders and psychiatric disorders. For safety, we calculated NNTH for serious adverse events. Meta-analysis was undertaken using a random-effects model. We assessed the quality of evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We included 16 studies with 1750 participants. The studies were 2 to 26 weeks long and compared an oromucosal spray with a plant-derived combination of tetrahydrocannabinol (THC) and cannabidiol (CBD) (10 studies), a synthetic cannabinoid mimicking THC (nabilone) (two studies), inhaled herbal cannabis (two studies) and plant-derived THC (dronabinol) (two studies) against placebo (15 studies) and an analgesic (dihydrocodeine) (one study). We used the Cochrane 'Risk of bias' tool to assess study quality. We defined studies with zero to two unclear or high risks of bias judgements to be high-quality studies, with three to five unclear or high risks of bias to be moderate-quality studies, and with six to eight unclear or high risks of bias to be low-quality studies. Study quality was low in two studies, moderate in 12 studies and high in two studies. Nine studies were at high risk of bias for study size. We rated the quality of the evidence according to GRADE as very low to moderate.Primary outcomesCannabis-based medicines may increase the number of people achieving 50% or greater pain relief compared with placebo (21% versus 17%; risk difference (RD) 0.05 (95% confidence interval (CI) 0.00 to 0.09); NNTB 20 (95% CI 11 to 100); 1001 participants, eight studies, low-quality evidence). We rated the evidence for improvement in Patient Global Impression of Change (PGIC) with cannabis to be of very low quality (26% versus 21%;RD 0.09 (95% CI 0.01 to 0.17); NNTB 11 (95% CI 6 to 100); 1092 participants, six studies). More participants withdrew from the studies due to adverse events with cannabis-based medicines (10% of participants) than with placebo (5% of participants) (RD 0.04 (95% CI 0.02 to 0.07); NNTH 25 (95% CI 16 to 50); 1848 participants, 13 studies, moderate-quality evidence). We did not have enough evidence to determine if cannabis-based medicines increase the frequency of serious adverse events compared with placebo (RD 0.01 (95% CI -0.01 to 0.03); 1876 participants, 13 studies, low-quality evidence).Secondary outcomesCannabis-based medicines probably increase the number of people achieving pain relief of 30% or greater compared with placebo (39% versus 33%; RD 0.09 (95% CI 0.03 to 0.15); NNTB 11 (95% CI 7 to 33); 1586 participants, 10 studies, moderate quality evidence). Cannabis-based medicines may increase nervous system adverse events compared with placebo (61% versus 29%; RD 0.38 (95% CI 0.18 to 0.58); NNTH 3 (95% CI 2 to 6); 1304 participants, nine studies, low-quality evidence). Psychiatric disorders occurred in 17% of participants using cannabis-based medicines and in 5% using placebo (RD 0.10 (95% CI 0.06 to 0.15); NNTH 10 (95% CI 7 to 16); 1314 participants, nine studies, low-quality evidence).We found no information about long-term risks in the studies analysed.Subgroup analysesWe are uncertain whether herbal cannabis reduces mean pain intensity (very low-quality evidence). Herbal cannabis and placebo did not differ in tolerability (very low-quality evidence).

AUTHORS' CONCLUSIONS

The potential benefits of cannabis-based medicine (herbal cannabis, plant-derived or synthetic THC, THC/CBD oromucosal spray) in chronic neuropathic pain might be outweighed by their potential harms. The quality of evidence for pain relief outcomes reflects the exclusion of participants with a history of substance abuse and other significant comorbidities from the studies, together with their small sample sizes.

Willingness to Participate in Longitudinal Research Among People with Chronic Pain Who Take Medical Cannabis: A Cross-Sectional Survey

Background: Regulatory barriers limit clinical trials of medical cannabis in the United States. Longitudinal cohort studies may be one feasible alternative that could yield clinically relevant information. Willingness to participate in such studies is not known.

Materials and Methods: In October 2016, we surveyed a convenience sample of patients with chronic pain from two New York registered organizations (responsible for growing, processing, distributing, and retailing medical cannabis products). After a vignette describing a longitudinal cohort study involving weekly patient-reported outcomes and quarterly assessments of physical functioning and urine and blood tests, we asked about respondents' willingness to participate. We examined willingness to participate, duration of participation, and frequency of data collections overall and by subgroups, using multivariable logistic regression models.

Results: Of 405 respondents (estimated response rate: 30%), 54% were women and 81% were white non-Hispanic. Neuropathy was the most common pain condition (67%) followed by inflammatory bowel disease (19%). Of respondents, 94% (95% CI 92–97%) thought that the study should be done, 85% (95% CI 81–88%) would definitely or probably enroll if asked, 76% (95% CI 72–81%) would participate for ≥1 year, and 59% (95% CI 54–64%) would respond to questions at least daily. Older age was the only factor associated with lower willingness to participate, lower willingness to participate for ≥1 year, and lower willingness to respond to questions at least daily.

Conclusions: Nearly all respondents were supportive of the proposed study and most reported that they would enroll if asked. Enhanced engagement with older individuals may be needed to promote equal enrollment. Recruitment for longitudinal cohort studies with frequent data collection appears feasible in this patient population.

Medical Cannabis for the Treatment of Inflammation

The connection between Cannabis sativa‘s chemical compounds and their ability to treat three different inflammatory ailments including bowel diseases, (IBD, e.g., Crohn's and ulcerative colitis), neuronal diseases (IND, e.g., Parkinson and Alzheimer), and a wide range of inflammatory skin diseases (ISD, e.g., atopic dermatitis and psoriasis) is presented. We review the range of experiments conducted over the last decade using either the whole extract of cannabis or separated mono-phytocannabinoids in the attempt to decipher the lead molecules, the receptors involved, the effects on genes and proteins, and especially the therapeutic potency of cannabis-derived compounds for treating these different inflammatory diseases. Along with the specifications for its current cutting-edge potential, the drawbacks and the designated needs for additional specific information from future research are indicated.

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.

The role of cannabinoids in pain control: the good, the bad, and the ugly

Cannabinoids appear to possess many potential medical uses, which may extend to pain control. A narrative review of the literature has found a variety of studies testing botanical and synthetic cannabinoids in different pain syndromes (acute pain, cancer pain, chronic noncancer pain, fibromyalgia pain, migraine, neuropathic pain, visceral pain, and others). Results from these studies are mixed; cannabinoids appear to be most effective in controlling neuropathic pain, allodynia, medication-rebound headache, and chronic noncancer pain, but do not seem to offer any advantage over nonopioid analgesics for acute pain. Cannabinoids seem to work no better than placebo for visceral pain and conferred only modest analgesic effect in cancer pain. Cannabinoids do many good things - they appear to be effective in treating certain types of pain without the issues of tolerance associated with opioids. Negatively, marijuana currently has a very murky legal status all over the world - laws regulating its use are inconsistent and in flux. Thus, both patients and prescribers may be unsure about whether or not it is an appropriate form of pain control. Cannabinoid-based analgesia has been linked to potential memory deficits and cognitive impairment. A great deal more remains to be elucidated about cannabinoids which may emerge to play an important role in the treatment of neuropathic and possibly other painful conditions. There remains a great deal more to learn about the role of cannabinoids in pain management.

The Endogenous Cannabinoid System: A Budding Source of Targets for Treating Inflammatory and Neuropathic Pain

A great need exists for the development of new medications to treat pain resulting from various disease states and types of injury. Given that the endogenous cannabinoid (that is, endocannabinoid) system modulates neuronal and immune cell function, both of which play key roles in pain, therapeutics targeting this system hold promise as novel analgesics. Potential therapeutic targets include the cannabinoid receptors, type 1 and 2, as well as biosynthetic and catabolic enzymes of the endocannabinoids N-arachidonoylethanolamine and 2-arachidonoylglycerol. Notably, cannabinoid receptor agonists as well as inhibitors of endocannabinoid-regulating enzymes fatty acid amide hydrolase and monoacylglycerol lipase produce reliable antinociceptive effects, and offer opioid-sparing antinociceptive effects in myriad preclinical inflammatory and neuropathic pain models. Emerging clinical studies show that 'medicinal' cannabis or cannabinoid-based medications relieve pain in human diseases such as cancer, multiple sclerosis, and fibromyalgia. However, clinical data have yet to demonstrate the analgesic efficacy of inhibitors of endocannabinoid-regulating enzymes. Likewise, the question of whether pharmacotherapies aimed at the endocannabinoid system promote opioid-sparing effects in the treatment of pain reflects an important area of research. Here we examine the preclinical and clinical evidence of various endocannabinoid system targets as potential therapeutic strategies for inflammatory and neuropathic pain conditions.

Current evidence of cannabinoid-based analgesia obtained in preclinical and human experimental settings

Cannabinoids have a long record of recreational and medical use and become increasingly approved for pain therapy. This development is based on preclinical and human experimental research summarized in this review. Cannabinoid CB₁ receptors are widely expressed throughout the nociceptive system. Their activation by endogenous or exogenous cannabinoids modulates the release of neurotransmitters. This is reflected in antinociceptive effects of cannabinoids in preclinical models of inflammatory, cancer and neuropathic pain, and by nociceptive hypersensitivity of cannabinoid receptor-deficient mice. Cannabis-based medications available for humans mainly comprise Δ⁹ -tetrahydrocannabinol (THC), cannabidiol (CBD) and nabilone. During the last 10 years, six controlled studies assessing analgesic effects of cannabinoid-based drugs in human experimental settings were reported. An effect on nociceptive processing could be translated to the human setting in functional magnetic resonance imaging studies that pointed at a reduced connectivity within the pain matrix of the brain. However, cannabinoid-based drugs heterogeneously influenced the perception of experimentally induced pain including a reduction in only the affective but not the sensory perception of pain, only moderate analgesic effects, or occasional hyperalgesic effects. This extends to the clinical setting. While controlled studies showed a lack of robust analgesic effects, cannabis was nearly always associated with analgesia in open-label or retrospective reports, possibly indicating an effect on well-being or mood, rather than on sensory pain. Thus, while preclinical evidence supports cannabinoid-based analgesics, human evidence presently provides only reluctant support for a broad clinical use of cannabinoid-based medications in pain therapy.

SIGNIFICANCE

Cannabinoids consistently produced antinociceptive effects in preclinical models, whereas they heterogeneously influenced the perception of experimentally induced pain in humans and did not provide robust clinical analgesia, which jeopardizes the translation of preclinical research on cannabinoid-mediated antinociception into the human setting.

Marijuana Use and Organ Transplantation: a Review and Implications for Clinical Practice

PURPOSE OF REVIEW

Physicians of all disciplines must rapidly adjust their clinical practices following the expansion of marijuana legalization across the country. Organ transplantation teams are uniquely struggling in this gray zone with eight states having passed laws explicitly banning the denial of transplant listing based on a patient's use of medical marijuana. In this review, we examine the clinical evidence of marijuana use in transplant patients to enable psychiatric providers to meaningfully contribute to the relevant medical and psychiatric aspects of this issue in a unique patient population.

RECENT FINDINGS

There is no consensus among experts regarding marijuana use in transplantation patients. There are extant case reports of post-transplant complications attributed to marijuana use including membranous glomerulonephritis, ventricular tachycardia, and tacrolimus toxicity. However, recent studies suggest that the overall survival rates in kidney, liver, lung, and heart transplant patients using marijuana are equivalent to non-users. Transplant teams should not de facto exclude marijuana users from transplant listing but instead holistically evaluate a patient's candidacy, integrating meaningful medical, psychiatric, and social variables into the complex decision-making process. Psychiatric providers can play a key role in this process. Appropriate stewardship over donor organs, a limited and precious resource, will require a balance of high-clinical standards with inclusive efforts to treat as many patients as possible.

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.

The use of cannabis in response to the opioid crisis: A review of the literature

BACKGROUND

A staggering number of Americans are dying from overdoses attributed to prescription opioid medications (POMs). In response, states are creating policies related to POM harm reduction strategies, overdose prevention, and alternative therapies for pain management, such as cannabis (medical marijuana). However, little is known about how the use of cannabis for pain management may be associated with POM use.

PURPOSE

The purpose of this article is to examine state medical cannabis (MC) use laws and policies and their potential association with POM use and related harms.

METHODS

A systematic literature review was conducted to explore United States policies related to MC use and the association with POM use and related harms. Medline, PubMed, CINAHL, and Cochrane databases were searched to identify peer-reviewed articles published between 2010 and 2017. Using the search criteria, 11,513 records were identified, with 789 abstracts reviewed, and then 134 full-text articles screened for eligibility.

FINDINGS

Of 134 articles, 10 articles met inclusion criteria. Four articles were cross-sectional online survey studies of MC substitution for POM, six were secondary data analyses exploring state-level POM overdose fatalities, hospitalizations related to MC or POM harms, opioid use disorder admissions, motor vehicle fatalities, and Medicare and Medicaid prescription cost analyses. The literature suggests MC laws could be associated with decreased POM use, fewer POM-related hospitalizations, lower rates of opioid overdose, and reduced national health care expenditures related to POM overdose and misuse. However, available literature on the topic is sparse and has notable limitations.

CONCLUSIONS

Review of the current literature suggests states that implement MC policies could reduce POM-associated mortality, improve pain management, and significantly reduce health care costs. However, MC research is constrained by federal policy restrictions, and more research related to MC as a potential alternative to POM for pain management, MC harms, and its impact on POM-related harms and health care costs should be a priority of public health, medical, and nursing research.

Medical Cannabis, a Beneficial High in Treatment of Blepharospasm? An Early Observation

The objective of this study was to observe the effect of medical cannabis in benign essential blepharospasm (BEB) as an adjunct to botulinum toxin. A retrospective chart review was performed on patients certified for medical cannabis use for BEB from September 2015 to May 2016. Patient demographics and responses, cannabis history, and severity indices were collected. Ten patients were certified for medical cannabis use. Five met the inclusion criteria, which was any patient with a diagnosis of BEB receiving standard botulinum toxin treatment who had started medical cannabis treatment by a registered distributor within the state, and was contactable by phone. Four patients discontinued use. Three out of four patients (75%) reported symptomatic improvement. Medical cannabis is an accepted therapy for muscle spastic disorders. Its potential as an adjunctive therapy for BEB remains unknown, and further investigations would be of benefit.

Drug therapy for chronic idiopathic axonal polyneuropathy

BACKGROUND

Chronic idiopathic axonal polyneuropathy (CIAP) is an insidiously progressive sensory or sensorimotor polyneuropathy that affects elderly people. Although severe disability or handicap does not occur, CIAP reduces quality of life. CIAP is diagnosed in 10% to 25% of people referred for evaluation of polyneuropathy. There is a need to gather and review emerging evidence on treatments, as the number of people affected is likely to increase in ageing populations. This is an update of a review first published in 2004 and previously updated in 2006, 2008, 2011 and 2013.

OBJECTIVES

To assess the effects of drug therapy for chronic idiopathic axonal polyneuropathy for reducing disability and ameliorating neurological symptoms and associated impairments, and to assess any adverse effects of treatment.

SEARCH METHODS

In July 2016, we searched Cochrane Central Register of Controlled Trials and the Cochrane Database of Systematic Reviews in the Cochrane Library, MEDLINE, Embase, and the Web of Science. We searched two trials registries for ongoing trials. We also handsearched the reference lists of relevant articles, reviews and textbooks identified electronically, and we would have contacted authors and other experts in the field to identify additional studies if this seemed useful.

SELECTION CRITERIA

We sought all randomised or quasi-randomised (alternate or other systematic treatment allocation) trials that examined the effects of any drug therapy in people with CIAP at least one year after the onset of treatment. People with CIAP had to fulfil the following criteria: age 40 years or older, distal sensory or sensorimotor polyneuropathy, absence of systemic or other neurological disease, chronic clinical course not reaching a nadir in less than two months, exclusion of any recognised cause of the polyneuropathy by medical history taking, clinical or laboratory investigations, and electrophysiological studies in agreement with axonal polyneuropathy, without evidence of demyelinating features. The primary outcome was the proportion of participants with a significant improvement in disability. Secondary outcomes were change in the mean disability score, change in the proportion of participants who make use of walking aids, change in the mean Medical Research Council sum score, degree of pain relief and/or reduction of other positive sensory symptoms, change in the proportion of participants with pain or other positive sensory symptoms, and frequency of adverse effects.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed the results of the literature search and extracted details of trial methodology and outcome data of all potentially relevant trials.

MAIN RESULTS

We identified 39 studies and assessed them for possible inclusion in the review, but we excluded all of them because of insufficient quality or lack of relevance. We summarised evidence from non-randomised studies in the Discussion.

AUTHORS' CONCLUSIONS

Even though CIAP has been clearly described and delineated, no adequate randomised or quasi-randomised controlled clinical treatment trials have been performed. In their absence there is no proven efficacious drug therapy.

Gender differences among treatment-seeking adults with cannabis use disorder: Clinical profiles of women and men enrolled in the achieving cannabis cessation-evaluating N-acetylcysteine treatment (ACCENT) study

BACKGROUND AND OBJECTIVES

Recent evidence suggests that women may fare worse than men in cannabis trials with pharmacologic interventions. Identifying baseline clinical profiles of treatment-seeking cannabis-dependent adults could inform gender-specific treatment planning and development.

METHODS

The current study compared baseline demographic, cannabis use, and psychiatric factors between women (n = 86) and men (n = 216) entering the Achieving Cannabis Cessation-Evaluating N-acetylcysteine Treatment (ACCENT) study, a multi-site, randomized controlled trial conducted within the National Drug Abuse Treatment Clinical Trials Network.

RESULTS

Women reported greater withdrawal intensity (p = .001) and negative impact of withdrawal (p = .001), predominantly due to physiological and mood symptoms. Women were more likely to have lifetime panic disorder (p = .038) and current agoraphobia (p = .022), and reported more days of poor physical health (p = .006) and cannabis-related medical problems (p = .023). Women reporting chronic pain had greater mean pain scores than men with chronic pain (p = .006). Men and women did not differ on any measures of baseline cannabis use.

DISCUSSION AND CONCLUSIONS

Cannabis-dependent women may present for treatment with more severe and impairing withdrawal symptoms and psychiatric conditions compared to cannabis-dependent men. This might help explain recent evidence suggesting that women fare worse than men in cannabis treatment trials of pharmacologic interventions. Baseline clinical profiles of treatment-seeking adults can inform gender-specific treatment planning and development.

SCIENTIFIC SIGNIFICANCE

Cannabis-dependent women may benefit from integrated treatment focusing on co-occurring psychiatric disorders and targeted treatment of cannabis withdrawal syndrome.(Am J Addict 2017;26:136-144).

Experts' perspectives on the role of medical marijuana in oncology: A semistructured interview study

BACKGROUND

Expansion of medical marijuana (MM) laws in the United States may offer oncology new therapeutic options. However, the scientific evidence for MM remains in infancy. This study qualitatively explored professional opinion around the role of MM in cancer care.

METHODS

Semistructured interviews were administered to a sample of individuals with expertise at the interface of MM and oncology nationally. Key informant criteria included an oncologic clinical or research background and any of the following: publications, research, or lectures on cannabinoids or cancer symptoms; involvement in the development of MM dispensaries or legislation; and early adoption of state MM certification procedures. A gold standard, grounded, inductive approach was used to identify underlying themes.

RESULTS

Participants (N = 15) were predominantly male, in their sixth decade, working in academic settings. Themes ranged from strong beliefs in marijuana's medical utility to reservations about this notion, with calls for expansion of the scientific evidence base and more stringent MM production standards. All participants cited nausea as an appropriate indication, and 13 of 15 pain. Over one-third believed MM to have a more attractive risk profile than opioids and benzodiazepines.

CONCLUSIONS

Expert opinion was divided between convictions in marijuana's medicinal potential and guardedness in this assertion, with no participant refuting MM's utility outright. Emergent themes included that MM ameliorates cancer-related pain and nausea and is safer than certain conventional medications. Participants called for enhanced purity and production standards, and further research on MM's utility.

Prevalence and correlates of "Vaping" as a route of cannabis administration in medical cannabis patients

PURPOSE

To examine the prevalence and correlates of vaporization (i.e., "vaping") as a route of cannabis administration in a sample of medical cannabis patients.

PROCEDURES

Adults ages 21 and older (N=1485M age=45.1) who were seeking medical cannabis certification (either for the first time or as a renewal) at medical cannabis clinics in southern Michigan completed a screening assessment. Participants completed measures of route of cannabis administration, cannabis use, alcohol and other substance use.

FINDINGS

An estimated 39% (n=511) of the sample reported past-month cannabis vaping, but vaping as the sole route of cannabis administration was rare. Specifically, only 30 participants (2.3% of the full sample and 5.9% of those who reported any vaping) indicated vaping as the sole route of cannabis administration. The majority (87.3%) of those who reported vaping also reported smoking (combustion) as a route of cannabis administration. Being younger than age 44, having more than a high school education, engaging in nonmedical stimulant use, being a returning medical cannabis patient, and greater frequency of cannabis use were associated with higher odds of vaping at the bivariate level and with all variables considered simultaneously.

CONCLUSIONS

Vaping appears to be relatively common among medical cannabis patients, but is seldom used as the sole route of cannabis administration.

RESULTS

highlight the importance of monitoring trends in vaping and other substance use behaviors in this population and underscore the need for longitudinal research into the motives, correlates, and consequences of cannabis vaping in medical cannabis patients.

The impact of adolescent exposure to medical marijuana laws on high school completion, college enrollment and college degree completion

BACKGROUND

There is concern that medical marijuana laws (MMLs) could negatively affect adolescents. To better understand these policies, we assess how adolescent exposure to MMLs is related to educational attainment.

METHODS

Data from the 2000 Census and 2001-2014 American Community Surveys were restricted to individuals who were of high school age (14-18) between 1990 and 2012 (n=5,483,715). MML exposure was coded as: (i) a dichotomous "any MML" indicator, and (ii) number of years of high school age exposure. We used logistic regression to model whether MMLs affected: (a) completing high school by age 19; (b) beginning college, irrespective of completion; and (c) obtaining any degree after beginning college. A similar dataset based on the Youth Risk Behavior Survey (YRBS) was also constructed for confirmatory analyses assessing marijuana use.

RESULTS

MMLs were associated with a 0.40 percentage point increase in the probability of not earning a high school diploma or GED after completing the 12th grade (from 3.99% to 4.39%). High school MML exposure was also associated with a 1.84 and 0.85 percentage point increase in the probability of college non-enrollment and degree non-completion, respectively (from 31.12% to 32.96% and 45.30% to 46.15%, respectively). Years of MML exposure exhibited a consistent dose response relationship for all outcomes. MMLs were also associated with 0.85 percentage point increase in daily marijuana use among 12th graders (up from 1.26%).

CONCLUSIONS

Medical marijuana law exposure between age 14 to 18 likely has a delayed effect on use and education that persists over time.

Sex-dependent effects of cannabis-induced analgesia

BACKGROUND

Preclinical studies demonstrate that cannabinoid-mediated antinociceptive effects vary according to sex; it is unknown if these findings extend to humans.

METHODS

This retrospective analysis compared the analgesic, subjective and physiological effects of active cannabis (3.56-5.60% THC) and inactive cannabis (0.00% THC) in male (N=21) and female (N=21) cannabis smokers under double-blind, placebo-controlled conditions. Pain response was measured using the Cold-Pressor Test (CPT). Participants immersed their hand in cold water (4°C); times to report pain (pain sensitivity) and withdraw the hand (pain tolerance) were recorded. Subjective drug ratings were also measured.

RESULTS

Among men, active cannabis significantly decreased pain sensitivity relative to inactive cannabis (p<0.01). In women, active cannabis failed to decrease pain sensitivity relative to inactive. Active cannabis increased pain tolerance in both men women immediately after smoking (p<0.001); a trend was observed for differences between men and women (p<0.10). Active cannabis also increased subjective ratings of cannabis associated with abuse liability ('Take again,' 'Liking,' 'Good drug effect'), drug strength, and 'High' relative to inactive in both men and women (p<0.01).

CONCLUSIONS

These results indicate that in cannabis smokers, men exhibit greater cannabis-induced analgesia relative to women. These sex-dependent differences are independent of cannabis-elicited subjective effects associated with abuse-liability, which were consistent between men and women. As such, sex-dependent differences in cannabis's analgesic effects are an important consideration that warrants further investigation when considering the potential therapeutic effects of cannabinoids for pain relief.

Transmission pathways and mediators as the basis for clinical pharmacology of pain

INTRODUCTION

Mediators in pain transmission are the targets of a multitude of different analgesic pharmaceuticals. This review explores the most significant mediators of pain transmission as well as the pharmaceuticals that act on them. Areas covered: The review explores many of the key mediators of pain transmission. In doing so, this review uncovers important areas for further research. It also highlights agents with potential for producing novel analgesics, probes important interactions between pain transmission pathways that could contribute to synergistic analgesia, and emphasizes transmission factors that participate in transforming acute injury into chronic pain. Expert commentary: This review examines current pain research, particularly in the context of identifying novel analgesics, highlighting interactions between analgesic transmission pathways, and discussing factors that may contribute to the development of chronic pain after an acute injury.

Medical cannabis - the Canadian perspective

Cannabis has been widely used as a medicinal agent in Eastern medicine with earliest evidence in ancient Chinese practice dating back to 2700 BC. Over time, the use of medical cannabis has been increasingly adopted by Western medicine and is thus a rapidly emerging field that all pain physicians need to be aware of. Several randomized controlled trials have shown a significant and dose-dependent relationship between neuropathic pain relief and tetrahydrocannabinol – the principal psychoactive component of cannabis. Despite this, barriers exist to use from both the patient perspective (cost, addiction, social stigma, lack of understanding regarding safe administration) and the physician perspective (credibility, criminality, clinical evidence, patient addiction, and policy from the governing medical colleges). This review addresses these barriers and draws attention to key concerns in the Canadian medical system, providing updated treatment approaches to help clinicians work with their patients in achieving adequate pain control, reduced narcotic medication use, and enhanced quality of life. This review also includes case studies demonstrating the use of medical marijuana by patients with neuropathic low-back pain, neuropathic pain in fibromyalgia, and neuropathic pain in multiple sclerosis. While significant preclinical data have demonstrated the potential therapeutic benefits of cannabis for treating pain in osteoarthritis, rheumatoid arthritis, fibromyalgia, and cancer, further studies are needed with randomized controlled trials and larger study populations to identify the specific strains and concentrations that will work best with selected cohorts.