Short- and Long-Term Effects of Cannabis on Headache and Migraine

Alcohol and cannabis use for pain management: Translational findings of relative risks, benefits, and interactions

Chronic pain affects over 20% of the global population and contributes to the vast burden of psychiatric illness. While effective treatments for chronic pain remain limited, both alcohol and cannabis have been used for centuries to manage pain and closely associated negative affective symptoms. However, persistent misuse of alcohol and/or cannabis in such a negative reinforcement fashion is hypothesized to increase the risk of severity of substance use disorders (SUDs). The current review describes neurobiological evidence for the analgesic efficacy of alcohol and primary cannabis constituents and how use or co-use of these substances may influence SUD risk.

High-Potency Cannabis Use and Health: A Systematic Review of Observational and Experimental Studies

OBJECTIVE

Amid continuously rising concentrations of delta-9-tetrahydrocannabinol (THC) in cannabis (i.e., potency), high-potency cannabis is a major topic in contemporary cannabis policy discussions, yet its impact on health is not well understood. The authors conducted a systematic review of observational and experimental studies examining the relationship between high-potency cannabis use and a range of health outcomes.

METHODS

Records were obtained from a systematic search of five biomedical research databases. The authors developed ecologically relevant potency (percent THC) exposure-comparison categories (1%-9%, 10%-19%, 20%-30%, kief/resin [∼30%-50%], concentrates [≥60%]) and used a landmark scientific report on cannabis and cannabinoids to determine outcome eligibility. Two reviewers independently conducted article screening and selection, extraction, and quality assessment. Findings were synthesized using both quantitative (association direction, binomial test) and narrative approaches. Certainty in the evidence was determined via the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework.

RESULTS

Of 4,545 screened records, 42 were eligible. Most studies addressed outcomes in the mental health, "problem" cannabis use, and other substance use domains. Findings in the "problem" cannabis use domain were suggestive of an association with higher-potency cannabis use. Findings were less consistent in other domains but tended to favor poorer outcomes with higher-potency use. Therapeutic outcomes were limited and mixed. Overall, certainty in the evidence was "very low."

CONCLUSIONS

Findings within the "problem" cannabis use domain were suggestive of an association with high-potency use. Research is largely limited to cross-sectional studies spanning few adverse health domains, underscoring the need for prospective studies probing therapeutic, cardiorespiratory, cancer, and pre- and perinatal outcomes. Policies to curb high-potency cannabis use may be warranted while the evidence base improves.

Detecting and understanding potential stigma among medical cannabis users in Germany

BACKGROUND

Despite its increasing prevalence among the public, cannabis use is still perceived as deviant behavior and consequently stigmatized. However, there remains a paucity of understanding regarding the impact of this stigma on patients employing cannabis for therapeutic purposes. This qualitative research endeavored to explore the stigma experiences of medical cannabis (MC) users in Germany, aiming to discern challenges that may impede their daily lives and healthcare access. The primary objective of this study was to identify instances of stigma associated with MC usage across various spheres.

METHODS

We conducted semistructured interviews with 15 individuals prescribed MC across diverse regions and occupational backgrounds in Germany. Interviews explored personal experiences with MC use, interactions with healthcare professionals, and stigma-related challenges. Data collection adhered to the COREQ guidelines. Transcribed interviews underwent systematic qualitative content analysis using MAXQDA software, with coding developed iteratively through researcher discussions. Communicative validation and inter-coder comparison enhanced analytical robustness.

RESULTS

Despite participants exhibiting a positive attitude towards the therapeutic effects and benefits of MC, stereotypes and prejudices persist. Participants highlighted the role of media portrayals and a lack of public awareness as central barriers to broader societal acceptance. Personal experiences with MC were marked by improved quality of life but also internalised stigma and external challenges, including interactions with law enforcement and difficulties with healthcare access.

CONCLUSION

This qualitative study suggests that the utilisation of MC remains inadequately normalised in Germany. Our findings indicate that MC users experience both substantial benefits and persistent challenges, with stigma remaining a key issue. While participants reported improvements in quality of life, barriers such as bureaucratic hurdles and knowledge gaps among healthcare professionals hinder access to appropriate care. The findings underscore the imperative for enhanced education among healthcare professionals.

Cannabinoids in Chronic Pain Management: A Review of the History, Efficacy, Applications, and Risks

Background/Objectives: Chronic pain remains a pervasive and challenging public health issue, often resistant to conventional treatments such as opioids, which carry substantial risks of dependency and adverse effects. Cannabinoids, bioactive compounds derived from the Cannabis sativa plant and their synthetic analogs, have emerged as a potential alternative for pain management, leveraging their interaction with the endocannabinoid system to modulate pain and inflammation. Methods: The current, evolving literature regarding the history, efficacy, applications, and safety of cannabinoids in the treatment of chronic pain was reviewed and summarized to provide the most current review of cannabinoids. Results: Evidence suggests that cannabinoids provide moderate efficacy in managing neuropathic pain, fibromyalgia, cancer-related pain, and multiple sclerosis-related spasticity. Patient-reported outcomes further indicate widespread perceptions of cannabinoids as a safer alternative to opioids, with potential opioid-sparing effects. However, the quality of existing evidence is limited by small sample sizes and methodological inconsistencies. Regulatory barriers, including the classification of cannabis as a Schedule I substance in the United States, continue to hinder robust research and clinical integration. Moreover, the risks associated with cannabinoids, such as psychiatric effects, addiction potential, and drug interactions, necessitate cautious application. Conclusions: Cannabinoids represent a promising, albeit complex, alternative for chronic pain management, particularly given the limitations and risks of traditional therapies such as opioids. However, significant deficiencies remain in the research. While smaller trials and systematic reviews indicate therapeutic potential, the quality of evidence is often low due to limited sample sizes, short study durations, and methodological inconsistencies. Large-scale, randomized controlled trials with long-term follow-up are urgently needed to confirm efficacy and safety across diverse patient populations and pain etiologies.

Combined effects of cannabidiol and Δ9-tetrahydrocannabinol alleviate migraine-like symptoms in mice

BACKGROUND

The therapeutic use of cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) to treat migraine has been understudied. Using three mouse models, we examined the impact of CBD and THC on migraine-relevant behaviors triggered by: 1) calcitonin gene-related peptide (CGRP), 2) sodium nitroprusside (SNP), and 3) cortical spreading depolarization (CSD).

METHODS

Both male and female CD1 mice were treated with CBD (100 mg/kg) or THC (1 mg/kg) alone or in combinations of CBD (1, 30 or 100 mg/kg) and THC (1 mg/kg) prior to injection of CGRP or SNP. The mice were assessed for light aversion (photophobia), squint (non-evoked pain), and periorbital tactile hypersensitivity, as well as possible adverse effects. In a separate set of experiments, CSD events were optogenetically induced in familial hemiplegic migraine 1 (FHM1) mutant and wildtype littermates (WT) mice (C57BL/6 background), followed by grimace and motor assessments with and without combinations of CBD (30 or 100 mg/kg) and THC (1 mg/kg).

RESULTS

In CD1 mice, a 100:1 CBD:THC combination mitigated light aversion induced by CGRP and SNP in males and females. Rescue of CGRP- and SNP-induced squint was observed only in male mice with 100:1 CBD:THC. None of the treatments rescued periorbital tactile hypersensitivity in either sex. In FHM1 mutant and WT mice, the 100:1 CBD:THC ratio did not affect CSD characteristics but did reduce CSD-induced grimace features (i.e., head pain mimic). No adverse effects of any of the cannabinoid treatments were observed using cognitive, emotional, or motor tests.

CONCLUSIONS

A 100:1 ratio of CBD:THC has a beneficial effect on some of the most bothersome migraine-related symptoms in three mouse models. Our findings support a potential therapeutic efficacy of combined CBD and THC treatments.

Natural Products Derived from Cannabis sativa for Pain Management

Cannabis sativa is one of the oldest medicinal plants in human history. Even ancient physicians from hundreds of years ago used Cannabis sativa to treat several conditions like pain. In the modern era, the research community, including health-care providers, have witnessed wide-scale changes in cannabis policy, legislation, and marketing, with a parallel increase in patient interest. A simple search in PubMed using "cannabis and pain" as keywords provides more than 2,400 articles, about 80% of which were published in the last 8-10 years. Several advancements have been achieved in understanding the complex chemistry of cannabis along with its multiple pharmacological activities. Preclinical data have demonstrated evidence for the promising potential of cannabis for pain management, and the continuous rise in the prevalence of pain increases the urgency to translate this into clinical practice. Despite the large body of cannabis literature, researchers still need to find rigorous answers for the questions about the efficacy and safety of cannabis in treatment of certain disorders such as pain. In the current chapter, we seek to present a critical overview about the current knowledge on cannabis with special emphasis on pain-related disorders.

Cannabis use disorder increases risk of large-artery atherosclerotic stroke and migraine with aura through mendelian randomization study

Observational studies have shown some association between cannabis use disorder (CUD) and neurological disorders, but their causal relationship is unclear. In this study, we tested the potential causal relationship between CUD and three common neurological disorders using two-sample Mendelian randomization (TSMR) and multivariate MR (MVMR) methods. Thirty-two genetic loci were extracted as exposure factors from the largest genome-wide association study (GWAS) summary statistics for CUD to date. TSMR results showed that genetic prediction of CUD with all stroke, ischemic stroke, large-artery atherosclerotic stroke, migraine with aura, and Alzheimer's disease (AD) had a positive causal relationship (P < 0.05), which was not found in several other diseases. The association between CUD and stroke, ischemic stroke, and AD in the MVMR study may have been influenced by confounding factors (P > 0.05). Subgroup analyses highlighted a causal relationship between genetically predicted CUD and large-artery atherosclerotic stroke (OR = 1.169; 95%CI 1.030-1.328; P = 0.016) and migraine with aura (OR = 1.142; 95% 1.021-1.278; P = 0.020). Our further functional mapping and annotation enrichment analyses using FUMA suggest that the brain-gut axis may serve as another layer of explanation for the existence of an association between CUD and neurological disorders.

A multi-centre, tolerability study of a cannabidiol-enriched Cannabis Herbal Extract for chronic headaches in adolescents: The CAN-CHA protocol

INTRODUCTION

Cannabis products have been used in the management of headaches in adults and may play a role in pediatric chronic pain. Canadian pediatricians report increasing use of cannabis for the management of chronic headaches, despite no well-controlled studies to inform its dosing, safety, and effectiveness. The aim of our clinical trial is to determine the dosing and safety of a Cannabidiol (CBD)-enriched Cannabis Herbal Extract (CHE) for the treatment of chronic headaches in adolescents.

METHODS AND ANALYSIS

Youth, parents, and an expert steering committee co-designed this tolerability study. Twenty adolescents (aged 14 to 17 years), with a chronic migraine diagnosis for more than 6 months that has not responded to other therapies will be enrolled into an open label, dose escalation study across three Canadian sites. Study participants will receive escalating doses of a CBD-enriched CHE (MPL-001 with a THC:CBD of 1:25), starting at 0.2-0.4 mg/kg of CBD per day and escalating monthly up to 0.8-1.0 mg/kg of CBD per day. The primary objective of this study is to determine the safety and tolerability of CBD-enriched CHE in adolescents with chronic migraine. Secondary objectives of this study will inform the development of subsequent randomized controlled trials and include investigating the relationship between the dose escalation and change in the frequency of headache, impact and intensity of pain, changes in sleep, mood, function, and quality of life. Exploratory outcomes include investigating steady-state trough plasma levels of bioactive cannabinoids and investigating how pharmacogenetic profiles affect cannabinoid metabolism among adolescents receiving CBD-enriched CHE.

DISCUSSION

This protocol was co-designed with youth and describes a tolerability clinical trial of CBD-enriched CHE in adolescents with chronic headaches that have not responded to conventional therapies. This study is the first clinical trial on cannabis products in adolescents with chronic headaches and will inform the development of future comparative effectiveness clinical trials.

TRIAL REGISTRATION

CAN-CHA trial is registered with ClinicalTrials.gov with a number of register NCT05337033.

The Use of Compounds Derived from Cannabis sativa in the Treatment of Epilepsy, Painful Conditions, and Neuropsychiatric and Neurodegenerative Disorders

Neurological disorders present a wide range of symptoms and challenges in diagnosis and treatment. Cannabis sativa, with its diverse chemical composition, offers potential therapeutic benefits due to its anticonvulsive, analgesic, anti-inflammatory, and neuroprotective properties. Beyond cannabinoids, cannabis contains terpenes and polyphenols, which synergistically enhance its pharmacological effects. Various administration routes, including vaporization, oral ingestion, sublingual, and rectal, provide flexibility in treatment delivery. This review shows the therapeutic efficacy of cannabis in managing neurological disorders such as epilepsy, neurodegenerative diseases, neurodevelopmental disorders, psychiatric disorders, and painful pathologies. Drawing from surveys, patient studies, and clinical trials, it highlights the potential of cannabis in alleviating symptoms, slowing disease progression, and improving overall quality of life for patients. Understanding the diverse therapeutic mechanisms of cannabis can open up possibilities for using this plant for individual patient needs.

Characterizing Cannabis Use and Perceived Benefit in a Tertiary Headache Center Patient Sample

Background and Objectives

Research suggests a potential role for cannabinoids in the etiology and treatment of migraine. However, there is a paucity of research on usage patterns and perceived benefits of cannabis use in clinical headache patient populations.

Methods

Patients from a tertiary headache center completed a 1-time online survey regarding cannabis use patterns and perceived benefits of cannabis-based products in treating migraine symptoms, clinical features, and risk factors (e.g., depression, sleep disturbance). Descriptive analyses were performed.

Results

Data were collected from 1373 patients (response rate 25.4% [1,373/5,400]), with 55.7% reporting cannabis-based product use in the past 3 years and 32.5% indicating current use. The most frequently cited reasons for cannabis-based product use were treating headache (65.8%) and sleep concerns (50.8%). Inhaled products (i.e., smoked/vaped) and edibles were the most commonly reported delivery methods, with THC/CBD (∆9 tetrahydrocannabinol/cannabidiol) blends as the most-cited product composition. A majority of participants reported cannabis-related improvements in migraine headache characteristics (i.e., intensity: 78.1%; duration: 73.4%; frequency: 62.4%), nausea (56.3%), and risk factors (sleep disturbance: 81.2%; anxiety: 71.4%; depression: 57.0%). Over half (58.0%) of the respondents reported only using cannabis products when experiencing a headache, while 42.0% used cannabis most days/daily for prevention. Nearly half (48.9%) of the respondents reported that cannabis use contributed to a reduction in medication amount for headache treatment, and 14.5% reported an elimination of other medications. A minority (20.9%) of participants reported experiencing side effects when using cannabis products for headache, most commonly fatigue/lethargy. For those participants who reported no use of cannabis-based products in the previous 3 years, approximately half indicated not knowing what cannabis product to take or the appropriate dosage.

Discussion

This is the largest study to date to document cannabis product usage patterns and perceived benefits for migraine management in a clinical headache patient sample. A majority of patients surveyed reported using cannabis products for migraine management and cited perceived improvements in migraine characteristics, clinical features, and associated risk factors. The findings warrant experimental trials to confirm the perceived benefits of cannabis products for migraine prevention and treatment.

Thoughtfully Integrating Cannabis Products Into Chronic Pain Treatment

Cannabis products (CPs) and cannabis-based medicines (CBMs) are becoming increasingly available and are commonly used for pain management. The growing societal acceptance of cannabis and liberalization of cannabis laws allows patients to access CPs with minimal clinical oversight. While there is mechanistic plausibility that CPs and CBMs may be useful for pain management, the clinical trial literature is limited and does not refute or support the use of CBMs for pain management. Complicating matters, a large and growing body of observational literature shows that many people use CPs for pain management and in place of other medications. However, products and dosing regimens in existing trials are not generalizable to the current cannabis market, making it difficult to compare and reconcile these 2 bodies of literature. Given this complexity, clinicians need clear, pragmatic guidance on how to appropriately educate and work with patients who are using CBMs for pain management. In this review, we narratively synthesize the evidence to enable a clear view of current landscape and provide pragmatic advice for clinicians to use when working with patients. This advice revolves around 3 principles: (1) maintaining the therapeutic alliance; (2) harm reduction and benefit maximization; and (3) pragmatism, principles of patient-centered care, and use of best clinical judgment in the face of uncertainty. Despite the lack of certainty CPs and chronic pain management use, we believe that following these principles can make most of the clinical opportunity presented by discussions around CPs and also enhance the likelihood of clinical benefit from CPs.

Medical Cannabis Prescription Practices and Quality of Life in Thai Patients: A Nationwide Prospective Observational Cohort Study

Introduction

The legalization of cannabis in Thailand has renewed interest in its traditional medical use. This study aimed to explore the prescribing patterns of traditional practitioners and assess the impact of cannabis oil on patients' quality of life, with a specific focus on comparing outcomes between cancer and non-cancer patients.

Methods

We conducted a prospective observational cohort study across 30 sites in 21 Thai provinces to analyze the use of "Ganja Oil," a cannabis extract in 10% coconut oil, prescribed for symptoms like pain, anorexia, and insomnia across a diverse patient group, including cancer and migraines. Quality of life was assessed using the Edmonton Symptom Assessment Scale (ESAS) and EQ-5D-5L at baseline, 1, 2, and 3 months. The study included a predefined subgroup analysis to compare the effects on cancer versus non-cancer patients. Data management was facilitated through Research Electronic Data Capture (REDCap), with statistical analysis performed using Stata/MP.

Results

Among 21,284 participants, the mean age was 54.10 ± 15.32 years, with 52.49% being male. The baseline EQ-5D-5L index was 0.85 ± 0.24. Significant differences in EQ-5D-5L indices were seen between cancer patients (0.79 ± 0.32) and non-cancer patients (0.85 ± 0.23; p < 0.001). ESAS scores also differed significantly between these groups for all symptoms, except anxiety. The most frequent prescription of Ganja Oil was oral administration at bedtime (88.26%), with the predominant dosage being three drops daily, approximately 0.204 mg of tetrahydrocannabinol in total. Posttreatment, significant improvements were noted: the EQ-5D-5L index increased by 0.11 points (95% CI: 0.11, 0.11; p < 0.001) overall, 0.13 points (95% CI: 0.12, 0.14; p < 0.001) for cancer patients, and 0.11 points (95% CI: 0.10, 0.11; p < 0.001) for non-cancer patients. ESAS pain scores improved by -2.66 points (95% CI: -2.71, -2.61; p < 0.001) overall, -2.01 points (95% CI: -2.16, -1.87; p < 0.001) for cancer patients, and -2.75 points (95% CI: -2.80, -2.70; p < 0.001) for non-cancer patients, with similar significant improvements in other symptoms.

Conclusion

Our study indicates potential benefits of Ganja Oil for improving quality of life among Thai patients, as a complementary treatment. These findings must be viewed in light of the study's design limitations. Further controlled studies are essential to ascertain its efficacy and inform dosing guidelines.

Cannabis use in context: Relations among impulsive personality traits, context, and cannabis problems

INTRODUCTION

Impulsive personality traits are associated with cannabis problems. Person-Environment Transactions Theory suggests that highly impulsive individuals behave differently in certain contexts, however little research has focused on the context in which cannabis is used. Therefore, the current study tested whether impulsive traits moderated relations between cannabis use contexts (social vs. solitary) and cannabis problems.

METHOD

In this cross-sectional study, college student who use cannabis (N = 435; 60.7% female) reported on their impulsive traits (i.e., negative urgency, positive urgency, premeditation, perseverance, and sensation seeking), typical cannabis use context (i.e., alone, with friends), typical cannabis use frequency, and past 30-day cannabis problems.

RESULTS

Both solitary cannabis use and negative urgency were associated with more cannabis problems. There were significant interactions between negative urgency and solitary cannabis use and lack of perseverance and solitary cannabis use, such that high and mean (but not low) levels of both negative urgency and lack of perseverance were associated with more cannabis problems the more frequently an individual used cannabis alone. There was also a significant interaction between sensation seeking and social cannabis use, such that high and mean (but not low) levels of sensation seeking were associated with cannabis problems for individuals who used cannabis more socially.

CONCLUSIONS

Findings suggest that impulsivity may potentiate risk for cannabis problems depending on the context in which cannabis is used. Prevention efforts may benefit from targeting protective strategy use in certain cannabis use contexts based upon an individual's personality traits.

The Exploration of Cannabis and Cannabinoid Therapies for Migraine

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Vaporized cannabis extract-induced antinociception in male vs female rats with persistent inflammatory pain

ABSTRACT

Although preclinical studies generally report robust antinociceptive effects of cannabinoids in rodent persistent pain models, randomized controlled trials in chronic pain patients report limited pain relief from cannabis/cannabinoids. Differences between animal and human studies that may contribute to these discrepant findings include route of cannabis/cannabinoid administration, type of cannabis/cannabinoid, and how pain is measured. To address these factors, rats with complete Freund adjuvant (CFA)-induced hind paw inflammation were exposed acutely or repeatedly to vaporized cannabis extract that was either tetrahydrocannabinol (THC) or cannabidiol (CBD)dominant. One measure of evoked pain (mechanical threshold), 2 functional measures of pain (hind paw weight-bearing, and locomotor activity), and hind paw edema were assessed for up to 2 hours after vapor exposure. Acute exposure to vaporized THC-dominant extract (200 or 400 mg/mL) decreased mechanical allodynia and hind paw edema and increased hind paw weight-bearing and locomotor activity, with no sex differences. After repeated exposure to vaporized THC-dominant extract (twice daily for 3 days), only the antiallodynic effect was significant. Acute exposure to vaporized CBD-dominant cannabis extract (200 mg/mL) did not produce any effects in either sex; repeated exposure to this extract (100, 200, or 400 mg/mL) decreased mechanical allodynia in male rats only. Sex differences (or lack thereof) in the effects of vaporized cannabis extracts were not explained by sex differences in plasma levels of THC, CBD, or their major metabolites. These results suggest that although vaporized THC-dominant extract is likely to be modestly effective against inflammatory pain in both male and female rats, tolerance may develop, and the CBD-dominant extract may be effective only in male rats.

Mechanisms of cannabinoid tolerance

Cannabis has been used recreationally and medically for centuries, yet research into understanding the mechanisms of its therapeutic effects has only recently garnered more attention. There is evidence to support the use of cannabinoids for the treatment of chronic pain, muscle spasticity, nausea and vomiting due to chemotherapy, improving weight gain in HIV-related cachexia, emesis, sleep disorders, managing symptoms in Tourette syndrome, and patient-reported muscle spasticity from multiple sclerosis. However, tolerance and the risk for cannabis use disorder are two significant disadvantages for cannabinoid-based therapies in humans. Recent work has revealed prominent sex differences in the acute response and tolerance to cannabinoids in both humans and animal models. This review will discuss evidence demonstrating cannabinoid tolerance in rodents, non-human primates, and humans and our current understanding of the neuroadaptations occurring at the cannabinoid type 1 receptor (CB1R) that are responsible tolerance. CB1R expression is downregulated in tolerant animals and humans while there is strong evidence of CB1R desensitization in cannabinoid tolerant rodent models. Throughout the review, critical knowledge gaps are indicated and discussed, such as the lack of a neuroimaging probe to assess CB1R desensitization in humans. The review discusses the intracellular signaling pathways that are responsible for mediating CB1R desensitization and downregulation including the action of G protein-coupled receptor kinases, β-arrestin2 recruitment, c-Jun N-terminal kinases, protein kinase A, and the intracellular trafficking of CB1R. Finally, the review discusses approaches to reduce cannabinoid tolerance in humans based on our current understanding of the neuroadaptations and mechanisms responsible for this process.

A Retrospective Medical Record Review of Adults with Non-Cancer Diagnoses Prescribed Medicinal Cannabis

Research describing patients using medicinal cannabis and its effectiveness is lacking. We aimed to describe adults with non-cancer diagnoses who are prescribed medicinal cannabis via a retrospective medical record review and assess its effectiveness and safety. From 157 Australian records, most were female (63.7%; mean age 63.0 years). Most patients had neurological (58.0%) or musculoskeletal (24.8%) conditions. Medicinal cannabis was perceived beneficial by 53.5% of patients. Mixed-effects modelling and post hoc multiple comparisons analysis showed significant changes overtime for pain, bowel problems, fatigue, difficulty sleeping, mood, quality of life (all p < 0.0001), breathing problems (p = 0.0035), and appetite (p = 0.0465) Symptom Assessment Scale scores. For the conditions, neuropathic pain/peripheral neuropathy had the highest rate of perceived benefit (66.6%), followed by Parkinson's disease (60.9%), multiple sclerosis (60.0%), migraine (43.8%), chronic pain syndrome (42.1%), and spondylosis (40.0%). For the indications, medicinal cannabis had the greatest perceived effect on sleep (80.0%), followed by pain (51.5%), and muscle spasm (50%). Oral oil preparations of balanced delta-9-tetrahydrocannabinol/cannabidiol (average post-titration dose of 16.9 mg and 34.8 mg per day, respectively) were mainly prescribed. Somnolence was the most frequently reported side effect (21%). This study supports medicinal cannabis' potential to safely treat non-cancer chronic conditions and indications.

Cannabidiol and Delta-9-Tetrahydrocannabinol Interactions in Male and Female Rats With Persistent Inflammatory Pain

Cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC), 2 of the primary constituents of cannabis, are used by some individuals to self-treat chronic pain. It is unclear whether the pain-relieving effects of CBD alone and in combination with THC are consistent across genders and among types of pain. The present study compared the effects of CBD and THC given alone and in combination in male and female rats with Complete Freund's adjuvant-induced inflammatory pain. After induction of hindpaw inflammation, vehicle, CBD (0.05-2.5 mg/kg), THC (0.05-2.0 mg/kg), or a CBD:THC combination (3:1, 1:1, or 1:3 dose ratio) was administered i.p. twice daily for 3 days. Then on day 4, mechanical allodynia, thermal hyperalgesia, weight-bearing, and locomotor activity were assessed 0.5 to 4 hours after administration of the same dose combination. Hindpaw edema and open field (anxiety-like) behaviors were measured thereafter. THC alone was anti-allodynic and anti-hyperalgesic, and decreased paw thickness, locomotion, and open field behaviors. CBD alone was anti-allodynic and anti-hyperalgesic. When combined with THC, CBD tended to decrease THC effects on pain-related behaviors and exacerbate THC-induced anxiety-like behaviors, particularly in females. These results suggest that at the doses tested, CBD-THC combinations may be less beneficial than THC alone for the treatment of chronic inflammatory pain. PERSPECTIVE: The present study compared CBD and THC effects alone and in combination in male and female rats with persistent inflammatory pain. This study could help clinicians who prescribe cannabis-based medicines for inflammatory pain conditions determine which cannabis constituents may be most beneficial.

UK medical cannabis registry: assessment of clinical outcomes in patients with headache disorders

OBJECTIVES

Headache disorders are a common cause of disability and reduced health-related quality of life globally. Growing evidence supports the use of cannabis-based medicinal products (CBMPs) for chronic pain; however, a paucity of research specifically focuses on CBMPs' efficacy and safety in headache disorders. This study aims to assess changes in validated patient-reported outcome measures (PROMs) in patients with headaches prescribed CBMPs and investigate the clinical safety in this population.

METHODS

A case series of the UK Medical Cannabis Registry was conducted. Primary outcomes were changes from baseline in PROMs (Headache Impact Test-6 (HIT-6), Migraine Disability Assessment (MIDAS), EQ-5D-5L, Generalized Anxiety Disorder-7 (GAD-7) questionnaire and Single-Item Sleep Quality Scale (SQS)) at 1-, 3-, and 6-months follow-up. P-values <0.050 were deemed statistically significant.

RESULTS

Ninety-seven patients were identified for inclusion. Improvements in HIT-6, MIDAS, EQ-5D-5L and SQS were observed at 1-, 3-, and 6-months (p < 0.005) follow-up. GAD-7 improved at 1- and 3-months (p < 0.050). Seventeen (17.5%) patients experienced a total of 113 (116.5%) adverse events.

CONCLUSION

Improvements in headache/migraine-specific PROMs and general health-related quality of life were associated with the initiation of CBMPs in patients with headache disorders. Cautious interpretation of results is necessary, and randomized control trials are required to ascertain causality.

Potential effects of cannabinoids on audiovestibular function: A narrative review

The growing interest in the development of drugs that target the endocannabinoid system has extended to conditions that affect the audiovestibular pathway. The expression of cannabinoid (CB) receptors in that pathway has been widely demonstrated, indicating a therapeutic potential for drug development at this level. These medications may be beneficial for conditions such as noise-induced hearing loss, ototoxicity, or various forms of vertigo of central or peripheral origin. The therapeutic targets of interest include natural or synthetic compounds that act as CB1/CB2 receptor agonists/antagonists, and inhibitors of the endocannabinoid-degrading enzymes FAAH and MAGL. Furthermore, genetic variations implicated in the response to treatment and the development of related disorders such as epilepsy or migraine have been identified. Direct methods of administering these medications should be examined beyond the systemic strategy.

Cannabinoid Profiles in Medical Cannabis Users: Effects of Age, Gender, Symptoms, and Duration of Use

Introduction: Clinical trials remain the gold standard for evaluating efficacy, but there is increasing interest in using real-world evidence (RWE) to inform health care decision making. The aims of this observational study were to describe patterns of medical cannabis use, associated changes in symptom severity over time, and to evaluate change in cannabis dose over time for pain-related symptoms. Methods: Data were collected by Strainprint^™, an application that is HIPAA, PIPEDA, and PHIPA compliant. A total of 629 participants recorded data between May 2017 and August 2019. A total of 65 symptoms were grouped as Pain, Mental Health, Physical Symptoms, Seizures, Headaches/Migraines, and Other. Descriptive statistics and mixed-effects modeling were applied. Results: THC-dominant products were more frequently consumed for symptoms of pain and sleep, while CBD-dominant products were more frequently consumed for anxiety and depression. Male and female participants demonstrated significant differences in the type of cannabis they consumed. Females more frequently consumed CBD-dominant products, and males more frequently consumed balanced (THC:CBD) products. Oil use was more prominent among females, while vaping was more common among males. Product use also varied by age tertiles (<31; 31-39; >40 years). CBD-dominant products were more common among younger participants, <31 years, THC-dominant products were more common among the 31-39 years category and balanced (THC:CBD) products were common among older participants >41 years. Dosages of CBD-dominant and balanced (THC:CBD) products increased over time irrespective of symptom response. THC-dominant products demonstrated a significant relationship between dose and symptom reduction over time. Conclusions: Recognizing that RWE has important methodological limitations, we observed cannabis product preferences based on demographic characteristics, such as gender and age and the primary symptom treated such as pain and anxiety. Our study offers real-world insights into how participants use and respond to cannabis products and suggests important avenues and methodologies for future research.

Posttraumatic stress disorder, sleep and medical cannabis treatment: A daily diary study

Despite increasing use of Medical Cannabis (MC) among posttraumatic stress disorder (PTSD) patients, research is lacking on how MC treatment relates to PTSD symptomatology, in particular sleep disturbances. This study examines the time gap between MC use and sleep onset and its association with (1) number of awakenings throughout the night, (2) early awakenings, (3) nightmares. Each morning over a two week period, 77 licensed MC patients suffering from PTSD reported on the timing of previous night MC use and sleep disturbances. Within-person analyses found that shorter time gaps between previous night MC use and sleep start time was associated with lower likelihood of experiencing nightmares throughout the night, but it was not associated with nightly awakenings or waking up too early. Between-person analyses showed that individuals who used MC products with higher CBD concentrations reported fewer early awakenings. These preliminary results indicate that future research should test causal relations between MC use and sleep problems in PTSD patients. Future research is warranted in order to explore causal relationships between MC use, nightmares and insomnia in PTSD patients.

Efficacy and Safety of Medical Marijuana in Migraine Headache: A Systematic Review

Medical marijuana treatment for migraine is becoming more common, although the legality and societal acceptance of marijuana for medical purposes in the United States have been challenged by the stigma attached to it as a recreational drug. These substances function to reduce nociception and decrease the frequency of migraine by having an impact on the endocannabinoid system. Our study reviewed the clinical response, dosing, and side effects of marijuana in migraine management. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a literature search in PubMed, Google Scholar, and Science Direct, and nine studies were included in the systematic review. The studies demonstrated that medical marijuana has a significant clinical response by reducing the length and frequency of migraines. No severe adverse effects were noted. Due to its effectiveness and convenience, medical marijuana therapy may be helpful for patients suffering from migraines. However, additional clinical trials and observational studies with longer follow-ups are required to study the efficacy and safety of the drug.

Medical Cannabis for the Treatment of Migraine in Adults: A Review of the Evidence

Background

Medical cannabis (MC) has been hypothesized as an alternative therapy for migraines, given the undesirable side effects of current migraine medications. The objective of this review was to assess the effectiveness and safety of MC in the treatment of migraine in adults.

Methods

We searched PubMed, EMBASE, PsycINFO, CINAHL, and Web of Science for eligible studies in adults aged 18 years and older. Two reviewers independently screened studies for eligibility. A narrative synthesis of the included studies was conducted.

Results

A total of 12 publications involving 1,980 participants in Italy and the United States of America were included.

Medical cannabis significantly reduced nausea and vomiting associated with migraine attacks after 6 months of use. Also, MC reduced the number of days of migraine after 30 days, and the frequency of migraine headaches per month. MC was 51% more effective in reducing migraines than non-cannabis products. Compared to amitriptyline, MC aborted migraine headaches in some (11.6%) users and reduced migraine frequency. While the use of MC for migraines was associated with the occurrence of medication overuse headaches (MOH), and the adverse events were mostly mild and occurred in 43.75% of patients who used oral cannabinoid preparations.

Conclusions

There is promising evidence that MC may have a beneficial effect on the onset and duration of migraine headaches in adults. However, well-designed experimental studies that assess MC's effectiveness and safety for treating migraine in adults are needed to support this hypothesis.

Sex-specific mechanisms of tolerance for the cannabinoid agonists CP55,940 and delta-9-tetrahydrocannabinol (Δ9-THC)

RATIONALE

Tolerance to cannabinoids could limit their therapeutic potential. Male mice expressing a desensitization-resistant form (S426A/S430A) of the type-1 cannabinoid receptor (CB1R) show delayed tolerance to delta-9-tetrahydrocannabinol (∆9-THC) but not CP55,940. With more women than men using medical cannabis for pain relief, it is essential to understand sex differences in cannabinoid antinociception, hypothermia, and resultant tolerance.

OBJECTIVE

Our objective was to determine whether female mice rely on the same molecular mechanisms for tolerance to the antinociceptive and/or hypothermic effects of cannabinoids that we have previously reported in males. We determined whether the S426A/S430A mutation differentially disrupts antinociceptive and/or hypothermic tolerance to CP55,940 and/or Δ9-THC in male and female S426A/S430A mutant and wild-type littermates.

RESULTS

The S426A/S430A mutation conferred an enhanced antinociceptive response for ∆9-THC and CP55,940 in both male and female mice. While the S426A/S430A mutation conferred partial resistance to ∆9-THC tolerance in male mice, disruption of CB1R desensitization had no effect on tolerance to ∆9-THC in female mice. The mutation did not alter tolerance to the hypothermic effects of ∆9-THC or CP55,940 in either sex. Interestingly, female mice were markedly less sensitive to the antinociceptive effects of 30 mg/kg ∆9-THC and 0.3 mg/kg CP55,940 compared with male mice.

CONCLUSIONS

Our results suggest that disruption of the GRK/βarrestin2 pathway of desensitization alters tolerance to Δ9-THC but not CP55,940 in male but not female mice. As tolerance to Δ9-THC appears to develop differently in males and females, sex should be considered when assessing the therapeutic potential and dependence liability of cannabinoids.

Self-Reported Effects of Cannabis on ADHD Symptoms, ADHD Medication Side Effects, and ADHD-Related Executive Dysfunction

OBJECTIVE

People with ADHD are more likely to use cannabis but little is known about the effects of cannabis on ADHD symptoms, ADHD medication side effects, or ADHD-related executive dysfunction.

METHOD

Students (n = 1,738) completed an online survey containing measures of ADHD symptoms, cannabis use, perceived effects of cannabis on ADHD symptoms and medication side effects, as well as executive dysfunction.

RESULTS

Participants with ADHD who have used cannabis reported that cannabis has acute beneficial effects on many symptoms of ADHD (e.g., hyperactivity, impulsivity). Further, they perceived cannabis to improve most of their medication side effects (e.g., irritability, anxiety). Finally, cannabis use frequency was a significant moderator of the associations between symptom severity and executive dysfunction.

CONCLUSION

Results suggest people with ADHD may be using cannabis to self-medicate for many of their symptoms and medication side effects and that more frequent use may mitigate ADHD-related executive dysfunction.

Clinical Evidence of Cannabinoids in Migraine: A Narrative Review

The endocannabinoid system (ECS) influences many biological functions, and hence, its pharmacological modulation may be useful for several disorders, such as migraine. Preclinical studies have demonstrated that the ECS is involved in the modulation of trigeminal excitability. Additionally, clinical data have suggested that an endocannabinoid deficiency is associated with migraine. Given these data, phytocannabinoids, as well as synthetic cannabinoids, have been tried as migraine treatments. In this narrative review, the current clinical evidence of potential ECS involvement in migraine pathogenesis is summarized. Furthermore, studies exploring the clinical effects of phytocannabinoids and synthetic cannabinoids on migraine patients are reviewed.

The endocannabinoid system and related lipids as potential targets for the treatment of migraine-related pain

BACKGROUND

Migraine is a complex and highly disabling neurological disease whose treatment remains challenging in many patients, even after the recent advent of the first specific-preventive drugs, namely monoclonal antibodies that target calcitonin gene-related peptide. For this reason, headache researchers are actively searching for new therapeutic targets. Cannabis has been proposed for migraine treatment, but controlled clinical studies are lacking. A major advance in cannabinoid research has been the discovery of the endocannabinoid system (ECS), which consists of receptors CB1 and CB2; their endogenous ligands, such as N-arachidonoylethanolamine; and the enzymes that catalyze endocannabinoid biosynthesis or degradation. Preclinical and clinical findings suggest a possible role for endocannabinoids and related lipids, such as palmitoylethanolamide (PEA), in migraine-related pain treatment. In animal models of migraine-related pain, endocannabinoid tone modulation via inhibition of endocannabinoid-catabolizing enzymes has been a particular focus of research.

METHODS

To conduct a narrative review of available data on the possible effects of cannabis, endocannabinoids, and other lipids in migraine-related pain, relevant key words were used to search the PubMed/MEDLINE database for basic and clinical studies.

RESULTS

Endocannabinoids and PEA seem to reduce trigeminal nociception by interacting with many pathways associated with migraine, suggesting a potential synergistic or similar effect.

CONCLUSIONS

Modulation of the metabolic pathways of the ECS may be a basis for new migraine treatments. The multiplicity of options and the wealth of data already obtained in animal models underscore the importance of further advancing research in this area. Multiple molecules related to the ECS or to allosteric modulation of CB1 receptors have emerged as potential therapeutic targets in migraine-related pain. The complexity of the ECS calls for accurate biochemical and pharmacological characterization of any new compounds undergoing testing and development.

A Large-Scale Naturalistic Examination of the Acute Effects of Cannabis on Pain

Introduction: Cannabis use for pain relief is commonly reported, yet laboratory studies and clinical trials suggest that cannabinoids are weak analgesics, and it is unclear whether perceived reductions in pain from before to after cannabis use relate to factors such as dose, method of administration, phytocannabinoid content, or the age or gender of the user. We determined whether inhalation of cannabis decreased self-reported pain ratings as well as whether user gender, age, time, method of administration, tetrahydrocannabinol (THC)/cannabidiol (CBD) content, or dose of cannabis contribute to changes in these ratings. We also examined whether tolerance may develop to the analgesic effects of cannabis over time. Materials and Methods: Archival data were obtained from Strainprint^®, a medical cannabis app that allows patients to track symptoms before and after using different strains and doses of cannabis. Latent change score models and multilevel models were used to analyze data from 131,582 sessions in which inhaled cannabis was used to treat "muscle pain," "joint pain," or "nerve pain." Results: For all three pain symptoms, severity ratings decreased significantly after cannabis use. Women reported higher baseline and postcannabis pain severity than did men, and men reported larger decreases in pain than did women. Neither THC nor CBD content nor their interaction predicted reductions in pain ratings. However, vaping was associated with larger reductions in joint pain ratings than was smoking, and lower doses were associated with larger reductions in nerve pain ratings. Additionally, for all three pain symptoms, the dose of cannabis used to manage pain increased significantly over time. Conclusions: Inhaled cannabis reduces self-reported pain severity by ∼42-49%. However, these reductions appear to diminish across time, and patients use larger doses across time, suggesting that analgesic tolerance develops with continued use.

Cannabis-Based Medicines and Medical Cannabis in the Treatment of Nociplastic Pain

Nociplastic pain is defined as pain due to sensitization of the nervous system, without a sufficient underlying anatomical abnormality to explain the severity of pain. Nociplastic pain may be manifest in various organ systems, is often perceived as being more widespread rather than localized and is commonly associated with central nervous system symptoms of fatigue, difficulties with cognition and sleep, and other somatic symptoms; all features that contribute to considerable suffering. Exemplified by fibromyalgia, nociplastic conditions also include chronic visceral pain, chronic headaches and facial pain, and chronic musculoskeletal pain. It has been theorized that dysfunction of the endocannabinoid system may contribute to persistent pain in these conditions. As traditional treatments for chronic pain in general and nociplastic pain in particular are imperfect, there is a need to identify other treatment options. Cannabis-based medicines and medical cannabis (MC) may hold promise and have been actively promoted by the media and advocacy. The medical community must be knowledgeable of the current evidence in this regard to be able to competently advise patients. This review will briefly explain the understanding of nociplastic pain, examine the evidence for the effect of cannabinoids in these conditions, and provide simplified guidance for healthcare providers who may consider prescribing cannabinoids for these conditions.

Quality of Life and a Surveillant Endocannabinoid System

The endocannabinoid system (ECS) is an important brain modulatory network. ECS regulates brain homeostasis throughout development, from progenitor fate decision to neuro- and gliogenesis, synaptogenesis, brain plasticity and circuit repair, up to learning, memory, fear, protection, and death. It is a major player in the hypothalamic-peripheral system-adipose tissue in the regulation of food intake, energy storage, nutritional status, and adipose tissue mass, consequently affecting obesity. Loss of ECS control might affect mood disorders (anxiety, hyperactivity, psychosis, and depression), lead to drug abuse, and impact neurodegenerative (Alzheimer's, Parkinson, Huntington, Multiple, and Amyotrophic Lateral Sclerosis) and neurodevelopmental (autism spectrum) disorders. Practice of regular physical and/or mind-body mindfulness and meditative activities have been shown to modulate endocannabinoid (eCB) levels, in addition to other players as brain-derived neurotrophic factor (BDNF). ECS is involved in pain, inflammation, metabolic and cardiovascular dysfunctions, general immune responses (asthma, allergy, and arthritis) and tumor expansion, both/either in the brain and/or in the periphery. The reason for such a vast impact is the fact that arachidonic acid, a precursor of eCBs, is present in every membrane cell of the body and on demand eCBs synthesis is regulated by electrical activity and calcium shifts. Novel lipid (lipoxins and resolvins) or peptide (hemopressin) players of the ECS also operate as regulators of physiological allostasis. Indeed, the presence of cannabinoid receptors in intracellular organelles as mitochondria or lysosomes, or in nuclear targets as PPARγ might impact energy consumption, metabolism and cell death. To live a better life implies in a vigilant ECS, through healthy diet selection (based on a balanced omega-3 and -6 polyunsaturated fatty acids), weekly exercises and meditation therapy, all of which regulating eCBs levels, surrounded by a constructive social network. Cannabidiol, a diet supplement has been a major player with anti-inflammatory, anxiolytic, antidepressant, and antioxidant activities. Cognitive challenges and emotional intelligence might strengthen the ECS, which is built on a variety of synapses that modify human behavior. As therapeutically concerned, the ECS is essential for maintaining homeostasis and cannabinoids are promising tools to control innumerous targets.

Medical Cannabis for Headache Pain: a Primer for Clinicians

PURPOSE OF REVIEW

Public acceptance of Cannabis sativa L. (cannabis) as a therapeutic option grows despite lags in both research and clinician familiarity. Cannabis-whether as a medical, recreational, or illicit substance-is and has been commonly used by patients. With ongoing decriminalization efforts, decreased perception of harms, and increased use of cannabis in the treatment of symptoms and disease, it is critical for clinicians to understand the rationale for specific therapies and their medical and practical implications for patients. In view of the opioid crisis, overall patient dissatisfaction, and lack of adherence to current chronic pain and headache therapies, this review provides up-to-date knowledge on cannabis as a potential treatment option for headache pain.

RECENT FINDINGS

Research into the use of cannabinoids for disease treatment have led to FDA-approved drugs for seizures, nausea, and vomiting caused by cancer chemotherapy; and for decreased appetite and weight loss in people with HIV/AIDS. For a wide variety of conditions and symptoms (including chronic pain), cannabis has gained increasing acceptance in society. The effects of cannabidiol (CBD) and tetrahydrocannabinol (THC) in pain pathways have been significantly elucidated. An increasing number of retrospective studies have shown a decrease in pain scores after administration of cannabinoids, as well as long-term benefits such as reduced opiate use. Yet, there is no FDA-approved cannabis product for headache or other chronic pain disorders. More is being done to determine who is likely to benefit from cannabis as well as to understand the long-term effects and limitations of the treatment. Cannabis can refer to a number of products derived from the plant Cannabis sativa L. Relatively well-tolerated, these products come in different configurations, types, and delivery forms. Specific formulations of the plant have been shown to be an effective treatment modality for chronic pain, including headache. It is important for clinicians to know which product is being discussed as well as the harms, benefits, contraindications, interactions, and unknowns in order to provide the best counsel for patients.

Medical Cannabis, Headaches, and Migraines: A Review of the Current Literature

Cannabis has been long used since ancient times for both medical and recreational use. Past research has shown that cannabis can be indicated for symptom management disorders, including cancer, chronic pain, headaches, migraines, and psychological disorders (anxiety, depression, and post-traumatic stress disorder). Active ingredients in cannabis that modulate patients' perceptions of their conditions include Δ⁹‐tetrahydrocannabinol (THC), cannabidiol (CBD), flavonoids, and terpenes. These compounds work to produce effects within the endocannabinoid system to decrease nociception and decrease symptom frequency. Research within the United States of America is limited to date due to cannabis being classified as a schedule one drug per the Drug Enforcement Agency. Few anecdotal studies have found a limited relationship between cannabis use and migraine frequency. The purpose of the review article is to document the validity of how medical cannabis can be utilized as an alternative therapy for migraine management. Thirty-four relevant articles were selected after a thorough screening process using PubMed and Google Scholar databases. The following keywords were used: "Cannabis," "Medical Marijuana," "Headache," "Cannabis and Migraine," "Cannabis and Headache." This literature study demonstrates that medical cannabis use decreases migraine duration and frequency and headaches of unknown origin. Patients suffering from migraines and related conditions may benefit from medical cannabis therapy due to its convenience and efficacy.

Selective targeting of peripheral cannabinoid receptors prevents behavioral symptoms and sensitization of trigeminal neurons in mouse models of migraine and medication overuse headache

ABSTRACT

Migraine affects ∼15% of the world's population greatly diminishing their quality of life. Current preventative treatments are effective in only a subset of migraine patients, and although cannabinoids seem beneficial in alleviating migraine symptoms, central nervous system side effects limit their widespread use. We developed peripherally restricted cannabinoids (PRCBs) that relieve chronic pain symptoms of cancer and neuropathies, without appreciable central nervous system side effects or tolerance development. Here, we determined PRCB effectiveness in alleviating hypersensitivity symptoms in mouse models of migraine and medication overuse headache. Long-term glyceryl trinitrate (GTN, 10 mg/kg) administration led to increased sensitivity to mechanical stimuli and increased expression of phosphorylated protein kinase A, neuronal nitric oxide synthase, and transient receptor potential ankyrin 1 proteins in trigeminal ganglia. Peripherally restricted cannabinoid pretreatment, but not posttreatment, prevented behavioral and biochemical correlates of GTN-induced sensitization. Low pH-activated and allyl isothiocyanate-activated currents in acutely isolated trigeminal neurons were reversibly attenuated by PRCB application. Long-term GTN treatment significantly enhanced these currents. Long-term sumatriptan treatment also led to the development of allodynia to mechanical and cold stimuli that was slowly reversible after sumatriptan discontinuation. Subsequent challenge with a previously ineffective low-dose GTN (0.1-0.3 mg/kg) revealed latent behavioral sensitization and increased expression of phosphorylated protein kinase A, neuronal nitric oxide synthase, and transient receptor potential ankyrin 1 proteins in trigeminal ganglia. Peripherally restricted cannabinoid pretreatment prevented all behavioral and biochemical correlates of allodynia and latent sensitization. Importantly, long-term PRCB treatment alone did not produce any behavioral or biochemical signs of sensitization. These data validate peripheral cannabinoid receptors as potential therapeutic targets in migraine and medication overuse headache.

Nutraceuticals and Behavioral Therapy for Headache

PURPOSE OF REVIEW

Headache affects and disables at least 1 billion people worldwide. Patients and providers seek new therapies to relieve headache without the side effects and financial burden of current treatments. This narrative review highlights recent treatment advances in integrative headache medicine: nutraceuticals and behavioral therapies.

RECENT FINDINGS

Growing use of complementary and alternative medicine (CAM) therapies for headache (riboflavin, coenzyme Q10, magnesium, vitamin D, melatonin) alongside mainstream treatments is increasing with improving evidence of quality, safety, and tolerability. Increasing interest in medical cannabis is tempered by lack of evidence regarding safety and efficacy. Behavioral therapies including cognitive behavioral therapy (CBT), biofeedback, mindfulness-based stress reduction (MBSR), and acceptance and commitment therapy (ACT) improve patient resiliency and self-efficacy outcomes and reduce disability. The body of evidence for nutraceutical and behavioral CAM interventions for headache continues to grow and improve in quality. Providers and patients should educate themselves regarding CAM therapies as part of integrative headache management. Future studies should examine combinatorial trials of CAM therapies against current standards of headache care.

Acute Effects of Cannabis on Symptoms of Obsessive-Compulsive Disorder

BACKGROUND

Little is known about the the acute effects of cannabis on symptoms of OCD in humans. Therefore, this study sought to: 1) examine whether symptoms of OCD are significantly reduced after inhaling cannabis, 2) examine predictors (gender, dose, cannabis constituents, time) of these symptom changes and 3) explore potential long-term consequences of repeatedly using cannabis to self-medicate for OCD symptoms, including changes in dose and baseline symptom severity over time.

METHOD

Data were analyzed from the app Strainprint® which provides medical cannabis patients a means of tracking changes in symptoms as a function of different doses and strains of cannabis across time. Specifically, data were analyzed from 87 individuals self-identifying with OCD who tracked the severity of their intrusions, compulsions, and/or anxiety immediately before and after 1,810 cannabis use sessions spanning a period of 31 months.

RESULTS

Patients reported a 60% reduction in compulsions, a 49% reduction in intrusions, and a 52% reduction in anxiety from before to after inhaling cannabis. Higher concentrations of CBD and higher doses predicted larger reductions in compulsions. The number of cannabis use sessions across time predicted changes in intrusions, such that later cannabis use sessions were associated with smaller reductions in intrusions. Baseline symptom severity and dose remained fairly constant over time.

LIMITATIONS

The sample was self-selected, self-identified as having OCD, and there was no placebo control group.

CONCLUSIONS

Inhaled cannabis appears to have short-term beneficial effects on symptoms of OCD. However, tolerance to the effects on intrusions may develop over time.

Medical Cannabis Use and Pain: An Experience Sampling Study

Background: Little research has tested associations of pain and MC use after long-term treatment and through methods that have external validity outside experimental settings. The study examined associations of pain, associated painful experiences, and long-term medical cannabis (MC) use in chronic pain (CP) patients using a naturalistic daily diary study that provided novel and externally valid data. Methods: Data were obtained from 78 MC users with CP three times daily over a 10-day period (n_observations = 1,688). Mixed-effects models were used to test the associations between MC use and momentary experiences of pain, affect, and fatigue. Results: Within persons, elevated experiences of pain intensity were associated with greater intention to use MC within the next hour. No evidence was found that the time lapse since last MC use was associated with pain levels, negative affect, or fatigue. Conclusions: The results imply that after long-term use, CP patients intend to use MC in response to pain experiences. Yet, they may not actually achieve the pain relief. More research is needed to examine whether continued MC use despite lack of pain relief is related to relief of other symptoms (e.g., dependence, withdrawal) or positive benefits (e.g., general sense of well-being) or tolerance.

Migraine Frequency Decrease Following Prolonged Medical Cannabis Treatment: A Cross-Sectional Study

Background: Medical cannabis (MC) treatment for migraine is practically emerging, although sufficient clinical data are not available for this indication. This cross-sectional questionnaire-based study aimed to investigate the associations between phytocannabinoid treatment and migraine frequency. Methods: Participants were migraine patients licensed for MC treatment. Data included self-reported questionnaires and MC treatment features. Patients were retrospectively classified as responders vs. non-responders (≥50% vs. <50% decrease in monthly migraine attacks frequency following MC treatment initiation, respectively). Comparative statistics evaluated differences between these two subgroups. Results: A total of 145 patients (97 females, 67%) with a median MC treatment duration of three years were analyzed. Compared to non-responders, responders (n = 89, 61%) reported lower current migraine disability and lower negative impact, and lower rates of opioid and triptan consumption. Subgroup analysis demonstrated that responders consumed higher doses of the phytocannabinoid ms_373_15c and lower doses of the phytocannabinoid ms_331_18d (3.40 95% CI (1.10 to 12.00); p < 0.01 and 0.22 95% CI (0.05–0.72); p < 0.05, respectively). Conclusions: These findings indicate that MC results in long-term reduction of migraine frequency in >60% of treated patients and is associated with less disability and lower antimigraine medication intake. They also point to the MC composition, which may be potentially efficacious in migraine patients.

Practical Considerations of Hypotheses and Evidence in Cannabis Pharmacotherapy: Refining Expectations of Clinical Endocannabinoid Deficiency

An Industry founded on the promotion of presumed health and wellness benefits of cannabis use continues to grow in the United States, despite the lack of substantial evidence in support of the many claims being made. Several hypotheses exist regarding the role of endocannabinoids in human health and the pertinence of phytocannabinoids as pharmacotherapies for addressing their dysregulation. An opinion is offered regarding the tenuous nature of these assumptions and questions are raised regarding how best to interpret the complex metabolic interplay of the still vaguely defined endocannabinoid system.