Efficacy and tolerability of high-dose dronabinol maintenance in HIV-positive marijuana smokers: a controlled laboratory study

The Impact of Cannabis Use on Cognition in People with HIV: Evidence of Function-Dependent Effects and Mechanisms from Clinical and Preclinical Studies

PURPOSE OF REVIEW

Cannabis may have beneficial anti-inflammatory effects in people with HIV (PWH); however, given this population's high burden of persisting neurocognitive impairment (NCI), clinicians are concerned they may be particularly vulnerable to the deleterious effects of cannabis on cognition. Here, we present a systematic scoping review of clinical and preclinical studies evaluating the effects of cannabinoid exposure on cognition in HIV.

RECENT FINDINGS

Results revealed little evidence to support a harmful impact of cannabis use on cognition in HIV, with few eligible preclinical data existing. Furthermore, the beneficial/harmful effects of cannabis use observed on cognition were function-dependent and confounded by several factors (e.g., age, frequency of use). Results are discussed alongside potential mechanisms of cannabis effects on cognition in HIV (e.g., anti-inflammatory), and considerations are outlined for screening PWH that may benefit from cannabis interventions. We further highlight the value of accelerating research discoveries in this area by utilizing translatable cross-species tasks to facilitate comparisons across human and animal work.

Nabilone Impairs Spatial and Verbal Working Memory in Healthy Volunteers

Background: Memory impairments and psychosis-like experiences can be adverse effects of cannabis use. However, reports on the cognitive impact of cannabis use are not consistent. There are also limited studies on the psychotomimetic effects of cannabinoid compounds to reveal the association between cannabis and psychosis. Therefore, we investigated the effect of acute cannabinoid intoxication on verbal working memory (VWM) and spatial working memory (SWM) following oral doses of the synthetic cannabinoid agonist, nabilone (1-2 mg, oral). We further investigated the effect of nabilone on psychosis-like experiences (schizotypy scores) and associations of schizotypy with VWM and SWM. Methods: Healthy participants (n=28) completed spatial and digit span tasks across different delay conditions (0, 6, 12, and 18 sec) after receiving nabilone (1-2 mg, PO) or placebo in a randomized, double-blind, counterbalanced, crossover manner. A subset of participants completed a short battery of schizotypy measures (n=25). Results: Nabilone impaired VWM (p=0.03, weak effect size η2=0.02) and SWM (p=0.00016, η2=0.08). Nabilone did not significantly change overall schizotypy scores. Schizotypy scores were negatively correlated with working memory (WM) averaged across all delays and both modalities, under placebo (ρ=-0.41, p=0.04). In addition, there were significant negative correlations between occasions of cannabis use and overall WM averaged scores across drug treatments (ρ=-0.49, p=0.007) and under placebo (ρ=-0.45, p=0.004). The results showed that the drug effect in the less frequent cannabis users was more pronounced on the SWM (p<0.01) and VWM (p<0.01), whereas there appeared to be little drug effect in the frequent cannabis users. Conclusion: Low doses of synthetic cannabinoid impaired SWM and VWM, indicating that exogenous activation of the cannabinoid system influences cognitive performance. Further, the results replicated previous findings that schizotypy is correlated with deficits in WM. Clinical Trial Registry Name: Nabilone and caffeine effects on the perceptions of visually, auditory, tactile and multimodal illusions in healthy volunteers. Clinical Trial Registration Number: CT-2018-CTN-02561 (Therapeutic Goods Administration Clinical Trial Registry) and ACTRN12618001292268 (The Australian New Zealand Clinical Trials Registry).

Medical Cannabis Increases Appetite but Not Body Weight in Patients with Inflammatory Bowel Diseases

We aimed to elucidate the effect of Medical Cannabis (MC) on appetite and nutritional status among patients with inflammatory bowel disease (IBD). A case series of patients with IBD were initiating treatment with MC for disease-related symptoms, at the IBD clinic of a tertiary referral medical center. Patients' demographics, anthropometrics, medical history and treatment and MC use were systematically recorded. An appetite and food frequency questionnaire (SNAQ and FFQ) were filled before, and at 3 and 6 months of treatment. Patients with IBD initiating MC were enrolled (n = 149, age 39.0 ± 14.1 years, 42.3% female), and 33.6% (n = 50) were treated for improvement of nutritional status. A modest increase in appetite after 3 months was detected among all patients enrolled (Pv = 0.08), but there were no significant differences in energy or macronutrient intake, and in patients' body mass index (BMI). A significant appetite improvement after 3 months was detected among 34.0% (n = 17) of patients, but this was not associated with increased caloric intake or BMI at 3 or 6 months. Among patients without increased appetite after 3 months of MC therapy, BMI decreased at 6 months (24.1 ± 3.7 vs. 23.4 ± 3.6, Pv = 0.010). MC may be a potential strategy to improve appetite among some patients with IBD, but not caloric intake or BMI.

Should gastroenterologists prescribe cannabis? The highs, the lows and the unknowns

Cannabis, commonly known as marijuana, is a drug extracted from the Cannabis plant known for its psychotropic and medicinal properties. It has been used for healing purposes during ancient times, although its psychoactive components led to its restricted use in medicine. Nonetheless, cannabis is found to have modulatory effects on the endocannabinoid system exhibiting its medicinal role in the gastrointestinal (GI) system. Emerging animal and human studies demonstrate the influential effects of cannabis on a variety of GI diseases including inflammatory bowel disease, motility disorders and GI malignancies. It also has a regulatory role in GI symptoms including nausea and vomiting, anorexia, weight gain, abdominal pain, among others. However, both its acute and chronic use can lead to undesirable side effects such as dependency and addiction, cognitive impairment and cannabinoid hyperemesis syndrome. We will discuss the role of cannabis in the GI system as well as dosing strategies to help guide gastroenterologists to assess its efficacy and provide patient counseling before prescription of medical marijuana.

Cannabis and sleep disorders: not ready for prime time? A qualitative scoping review

STUDY OBJECTIVES

To perform a qualitative scoping literature review for studies involving the effects of cannabis on sleep and sleep disorders.

METHODS

Two electronic databases, MEDLINE and EMBASE, searched for comprehensive published abstracted studies that involved human participants. Inclusion criteria were article of any type, published in English, a target population of cannabis users, and reported data on cannabis effect on sleep and sleep disorders. The Joanna Briggs Institute's (JBI) approach was elected as the methodology framework guidance in the scoping review process.

RESULTS

A total of 40 unique publications were found. The majority (82.5%) were from the Americas with 60% published in the last decade. Of the 40 studies, only 25% were randomized control trials, and the sleep outcome measurements were similar and comparable in only 20%. Cannabis users studied were reported either 73% frequent users or 27% sporadic users. The utilization of cannabis showed improved sleep (21%), worse sleep (48%), mixed results (14%), or no impact at all (17%) in the studies published in the last 5 decades.

CONCLUSIONS

Our findings summarize the lack of robust evidence to support the use of cannabis for sleep disorders. The varied cannabis user-related characteristics may account for the inconsistent results identified. Further studies assessing cannabis and sleep are needed to discern what works in what context, how it works, and for whom.

CITATION

Amaral C, Carvalho C, Scaranelo A, Chapman K, Chatkin J, Ferreira I. Cannabis and sleep disorders: not ready for prime time? A qualitative scoping review. J Clin Sleep Med. 2023;19(5):975-990.

Delta-9 tetrahydrocannabinol (THC) effects on the cortisol stress response in bovine granulosa cells

Maternal stress can result in changes in the hypothalamic-pituitary-adrenal (HPA) axis and lead to stress-related behaviours in offspring. Under physiological conditions, delta-9 tetrahydrocannabinol (THC) appears to be detrimental for fertility. However, cannabis is also commonly used for stress-relief. THC acts on the endocannabinoid receptors in granulosa cells (GCs), which affect oocyte competency. The objective of this study was to evaluate the effects of THC on in vitro bovine granulosa cell viability, apoptosis, and stress response pathway. GCs were cultured in vitro in the presence of clinically relevant therapeutic and recreational plasma doses of THC. Cortisol doses reflecting normal and elevated plasma levels were used to evaluate the effects of THC under induced stress in vitro. No effect of THC was observed on cell viability or apoptosis. High and low cortisol concentrations caused significant increases in 11β-HSD1 mRNA expression (n = 6, p < 0.0001). Interestingly, when combined with high [THC], there was a significant decrease in 11β-HSD1 expression compared to high and low cortisol treatments alone (p < 0.001, p < 0.05). GR expression was unaffected by cortisol treatments, and low [THC] treatment maintained increased expression in the presence of high and low cortisol treatments (n = 6, p < 0.01, p < 0.0001). Our findings represent a foundation to obtain useful data for evaluating THC potential therapeutic benefit.

Using Alcohol and Cannabis as Sleep Aids: Associations with Descriptive Norms Among College Students

PURPOSE

Young adults may use alcohol and cannabis as sleep aids, a risky behavior that can worsen sleep health over time and lead to substance dependence. Perceived norms for such risky behaviors are often overestimated and related to one's own use. This cross-sectional study examined: (a) the extent to which college students overestimated the prevalence of alcohol and cannabis use as sleep aids (i.e., perceived descriptive norms), and (b) the extent to which perceived descriptive norms were associated with students' own use of alcohol and cannabis as sleep aids.

METHODS

2,642 undergraduate college students (Mage = 18.84 years) reported past 30-day use of alcohol and cannabis as sleep aids. Participants also estimated the percent of college students who use alcohol and cannabis as sleep aids (i.e., perceived descriptive norms).

RESULTS

One-sample t-tests revealed participants, on average, overestimated the norms for using alcohol and cannabis as sleep aids. Participants who endorsed past 30-day use of these substances as sleep aids overestimated these norms to an even greater extent. Count regression models showed perceived descriptive norms were associated with students' use of alcohol and of cannabis as sleeps aids, in respective models, even when controlling for sleep difficulties.

CONCLUSIONS

College students may overestimate the prevalence of using alcohol and cannabis as sleep aids, and students who believe these behaviors are more normative report more frequent use of these substances as sleep aids. Taken together, findings may highlight the potential for norm-correcting strategies as a prudent approach to reducing/preventing the use of alcohol and cannabis as sleep aids.

Medical cannabinoids: a pharmacology-based systematic review and meta-analysis for all relevant medical indications

BACKGROUND

Medical cannabinoids differ in their pharmacology and may have different treatment effects. We aimed to conduct a pharmacology-based systematic review (SR) and meta-analyses of medical cannabinoids for efficacy, retention and adverse events.

METHODS

We systematically reviewed (registered at PROSPERO: CRD42021229932) eight databases for randomized controlled trials (RCTs) of dronabinol, nabilone, cannabidiol and nabiximols for chronic pain, spasticity, nausea /vomiting, appetite, ALS, irritable bowel syndrome, MS, Chorea Huntington, epilepsy, dystonia, Parkinsonism, glaucoma, ADHD, anorexia nervosa, anxiety, dementia, depression, schizophrenia, PTSD, sleeping disorders, SUD and Tourette. Main outcomes and measures included patient-relevant/disease-specific outcomes, retention and adverse events. Data were calculated as standardized mean difference (SMD) and ORs with confidence intervals (CI) via random effects. Evidence quality was assessed by the Cochrane Risk of Bias and GRADE tools.

RESULTS

In total, 152 RCTs (12,123 participants) were analysed according to the type of the cannabinoid, outcome and comparator used, resulting in 84 comparisons. Significant therapeutic effects of medical cannabinoids show a large variability in the grade of evidence that depends on the type of cannabinoid. CBD has a significant therapeutic effect for epilepsy (SMD - 0.5[CI - 0.62, - 0.38] high grade) and Parkinsonism (- 0.41[CI - 0.75, - 0.08] moderate grade). There is moderate evidence for dronabinol for chronic pain (- 0.31[CI - 0.46, - 0.15]), appetite (- 0.51[CI - 0.87, - 0.15]) and Tourette (- 1.01[CI - 1.58, - 0.44]) and moderate evidence for nabiximols on chronic pain (- 0.25[- 0.37, - 0.14]), spasticity (- 0.36[CI - 0.54, - 0.19]), sleep (- 0.24[CI - 0.35, - 0.14]) and SUDs (- 0.48[CI - 0.92, - 0.04]). All other significant therapeutic effects have either low, very low, or even no grade of evidence. Cannabinoids produce different adverse events, and there is low to moderate grade of evidence for this conclusion depending on the type of cannabinoid.

CONCLUSIONS

Cannabinoids are effective therapeutics for several medical indications if their specific pharmacological properties are considered. We suggest that future systematic studies in the cannabinoid field should be based upon their specific pharmacology.

Potential Role of Cannabinoid Type 2 Receptors in Neuropsychiatric and Neurodegenerative Disorders

The endocannabinoid system (ECS) is composed of the two canonical receptor subtypes; type-1 cannabinoid (CB1R) and type 2 receptor (CB2R), endocannabinoids (eCBs) and enzymes responsible for the synthesis and degradation of eCBs. Recently, with the identification of additional lipid mediators, enzymes and receptors, the expanded ECS called the endocannabinoidome (eCBome) has been identified and recognized. Activation of CB1R is associated with a plethora of physiological effects and some central nervous system (CNS) side effects, whereas, CB2R activation is devoid of such effects and hence CB2Rs might be utilized as potential new targets for the treatment of different disorders including neuropsychiatric disorders. Previous studies suggested that CB2Rs were absent in the brain and they were considered as peripheral receptors, however, recent studies confirmed the presence of CB2Rs in different brain regions. Several studies have now focused on the characterization of its physiological and pathological roles. Studies done on the role of CB2Rs as a therapeutic target for treating different disorders revealed important putative role of CB2R in neuropsychiatric disorders that requires further clinical validation. Here we provide current insights and knowledge on the potential role of targeting CB2Rs in neuropsychiatric and neurodegenerative disorders. Its non-psychoactive effect makes the CB2R a potential target for treating CNS disorders; however, a better understanding of the fundamental pharmacology of CB2R activation is essential for the design of novel therapeutic strategies.

Is There a Place for Medicinal Cannabis in Treating Patients with Sleep Disorders? What We Know so Far

The legalization of cannabis for medicinal, and in some countries, recreational, purposes in addition to growth in the cannabis industry has meant that cannabis use and interest in the area has increased rapidly over the past 20 years. Treatment of poor sleep and sleep disorders are two of the most common reasons for the current use of medicinal cannabis. However, evidence for the role of medical cannabis in the treatment of sleep disorders has not been clearly established, thus making it challenging for clinicians to make evidence-based decisions regarding efficacy and safety. This narrative review summarizes the highest quality clinical evidence currently available in relation to the use of medicinal cannabis for the treatment of sleep disorders including insomnia, obstructive sleep apnea, restless legs syndrome, rapid eye movement sleep behavior disorder, nightmare disorder and narcolepsy. A summary of the effect of cannabis on sleep quality and architecture is also presented. Currently, there is insufficient evidence to support the routine use of medicinal cannabis as an effective and safe treatment option for any sleep disorder. Nevertheless, emerging evidence is promising and warrants further investigation using standardized cannabinoid products and validated quantitative measurement techniques.

Cannabis use and obesity-traits: A Mendelian randomization study

BACKGROUND

Observational studies suggested that cannabis use is associated with decreased body fatness; however, observational studies are subject to confounding, making causal inference and determining the direction of these associations difficult. We performed Mendelian randomization (MR) using summary statistics from genome-wide association studies (GWAS) to investigate the potential causal association of cannabis use and obesity-related traits.

METHODS

We used 51 single nucleotide polymorphisms (SNPs) associated with lifetime cannabis use at P 1<×  10^-5 from a GWAS of 184,765 individuals of European descent and 27 SNPs genome-wide associated with cannabis use disorder as instrumental variables. The GWAS for body mass index (BMI) was derived from a meta-analysis of up to 322,154 individuals, and the GWAS for waist circumference (WC) and waist-hip ratio (WHR) included 210,088 participants.

RESULTS

MR showed that lifetime cannabis use (beta = - 0.018, 95 % confidence interval (CI): - 0.05-0.015; P-value = 0.279, Q-value = 0.279) and cannabis use disorder (beta = 0.023, 95 % CI: 0.023-0.045; P-value = 0.034, Q-value = 0.092) were not associated with BMI. Considering WC and WHR as indicators of obesity, our findings did not support a causal association. Leave-one out analyses and pleiotropy-robust methods did not indicate bias in any of the estimates.

CONCLUSIONS

Overall, the MR study provides little evidence that cannabis influences obesity related traits.

Approved cannabinoids for medical purposes - Comparative systematic review and meta-analysis for sleep and appetite

BACKGROUND

Cannabinoids are used for numerous disease indications. However, cannabinoids can also produce adverse effects; for example, they can disturb physiological functions such as sleep and appetite. The medical use of cannabinoids refers to a wide variety of preparations and products. Approved cannabinoid products include dronabinol ((-)-trans-Δ⁹-tetrahydrocannabinol (THC), nabilone (a THC analogue), and cannabidiol (CBD) that differ in their pharmacology and may thus have different adverse effects on sleep and appetite.

OBJECTIVES

Here we ask if (i) cannabinoids decrease sleep and appetite in somatic patients or patients that suffer from mental illness and if (ii) there is a difference between THC products (nabilone, dronabinol), vs. CBD in disturbing these physiological functions.

METHODS

In order to answer these two questions, we performed a comparative systematic review (SR) for nabilone, dronabinol, and CBD. For the comparative SR we searched PubMed, Medline, Embase, and PsycINFO for randomized controlled trials (RCTs) and extracted information for adverse side effects or outcomes reporting a negative impact on sleep and appetite. RCT evidence was calculated as odds ratios (ORs) via fixed effects meta-analyses. Evidence quality was assessed by the Cochrane Risk of Bias and GRADE tools. This study is registered at PROSPERO (CRD42021229932).

FINDINGS

A total of 17 RCTs (n = 1479) and 15 RCTs (n = 1974) were included for sleep and appetite, respectively. Pharmaceutical THC (nabilone, dronabinol) does not affect sleep or appetite. In contrast, there is moderate evidence that CBD decreases appetite (OR = 2.46 [1.74:4.01] but has also no effect on sleep.

INTERPRETATIONS

Our comparative systematic study shows that approved cannabinoids can decrease appetite as a negative side effect - an effect that seems to be driven by CBD. Approved cannabinoid products do not negatively affect sleep in somatic and psychiatric patients. This article is part of the special Issue on "Cannabinoids".

Medical cannabis for the treatment of fibromyalgia syndrome: a retrospective, open-label case series

BACKGROUND

The use of cannabis for treating fibromyalgia syndrome (FMS) has not been comprehensively investigated. Thus, we have assessed the efficacy and adverse events (AEs) of short- and long-term medical cannabis (MC) treatment for FMS.

METHODS

Data were obtained from medical reports archived in the pain clinic of Ponderano (Italy; retrospective study). FMS patients, who were resistant to conventional therapy, received licensed MC with various Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) content, as powdered whole flowers (decoction or vaporization) or oil extracts. Demographic and clinical parameters, including Numerical Rating Scale (NRS), Oswestry Disability Index (ODI), Hospital Anxiety and Depression Scale, Widespread Pain Index (WPI), Severity Score (SyS), and side effects, were obtained after 1, 3, and 12 months. Data were analyzed with Wilcoxon signed-rank tests for paired data.

RESULTS

Thirty-eight patients were included. Thirty, 18, and 12 patients continued therapy for 1, 3, and 12 months, respectively. Significant improvements (p < 0.01) were observed in NRS, ODI, WPI, and SyS at 1 month; in NRS, ODI, and WPI at 3 months; and in NRS, ODI, and SyS at 12 months. Therapy was interrupted by 17 patients (48.6%) owing to nonserious AEs according to the FDA. The most common side effects were mental confusion (37%), dizziness (14%), nausea/vomiting (14%), and restlessness/irritation (14%). The median daily dose of milled flowers administered as THC-dominant MC and hybrid MC (with similar THC/CBD ratio) was 200 mg/day and 400 mg/day, respectively. After 3 months of titration, the median content of THC administered with THC-dominant MC cultivars was 46.2 mg, and of THC + CBD administered as a hybrid MC cultivar, was 23.6 mg + 38 mg. At 3 months, median THC content administered in the oil extract of the THC-dominant MC cultivars was 9.7 mg, while that of THC + CBD administered in the oil extract of the hybrid MC cultivars was 1.8 mg + 2 mg.

CONCLUSIONS

MC may represent an alternative treatment for patients with FMS who are unresponsive to conventional therapy. However, its application may be limited by the incidence of nonserious AEs.

Mini-review: The therapeutic role of cannabinoids in neuroHIV

In the era of combined antiretroviral therapy (cART), human immunodeficiency virus type 1 (HIV-1) is considered a chronic disease with an inflammatory component that specifically targets the brain and causes a high prevalence of HIV-1-associated neurocognitive disorders (HAND). The endocannabinoid (eCB) system has attracted interest as a target for treatment of neurodegenerative disorders, due to the potential anti-inflammatory and neuroprotective properties of cannabinoids, including its potential therapeutic use in HIV-1 neuropathogenesis. In this review, we summarize what is currently known about the structural and functional changes of the eCB system under conditions of HAND. This will be followed by summarizing the current clinical and preclinical findings on the effects of cannabis use and cannabinoids in the context of HIV-1 infection, with specifically focusing on viral load, cognition, inflammation, and neuroprotection. Lastly, we present some potential future directions to better understand the involvement of the eCB system and the role that cannabis use and cannabinoids play in neuroHIV.

Use of Medical Cannabis to Treat Traumatic Brain Injury

There is not a single pharmacological agent with demonstrated therapeutic efficacy for traumatic brain injury (TBI). With recent legalization efforts and the growing popularity of medical cannabis, patients with TBI will inevitably consider medical cannabis as a treatment option. Pre-clinical TBI research suggests that cannabinoids have neuroprotective and psychotherapeutic properties. In contrast, recreational cannabis use has consistently shown to have detrimental effects. Our review identified a paucity of high-quality studies examining the beneficial and adverse effects of medical cannabis on TBI, with only a single phase III randomized control trial. However, observational studies demonstrate that TBI patients are using medical and recreational cannabis to treat their symptoms, highlighting inconsistencies between public policy, perception of potential efficacy, and the dearth of empirical evidence. We conclude that randomized controlled trials and prospective studies with appropriate control groups are necessary to fully understand the efficacy and potential adverse effects of medical cannabis for TBI.

Cannabis use and sleep: Expectations, outcomes, and the role of age

STUDY OBJECTIVES

Determine relationship between cannabis use with 1) expectations of cannabis being a sleep aid, 2) subjective sleep outcomes, and 3) the influence of age on these relationships.

METHODS

In 152 moderate cannabis users with a wide age range (67% female, mean age = 31.45, SD = 12.96, age range = 21-70; mean days of cannabis use in prior two weeks = 5.54, SD = 5.25) we examined the influence of cannabis use history and behaviors on expectations of cannabis being a sleep aid and sleep outcomes via the Pittsburgh Sleep Quality Index (PSQI). Moderation analysis examined the role of age in the relationship between cannabis use and sleep outcomes.

RESULTS

Endorsing current cannabis use and more days of cannabis use were associated with increased expectations that cannabis use improves sleep (all β > 0.03, p < 0.04). Frequency of recent use and reported average THC or CBD concentration were largely not associated with sleep outcomes. However, endorsing current cannabis use was associated with worse subjective sleep quality (β = 1.34, p = 0.02) and increased frequency of consuming edibles was associated with worse subjective sleep efficiency (β = 0.03, p = 0.04), lower sleep duration (β = 0.03, p = 0.01), and higher global PSQI scores (worse overall sleep) (β = 0.10, p = 0.01). Additionally, age had a moderating influence on the relationship between increased self-reported concentration of CBD and both better sleep duration and sleep quality (both p < 0.03). While the main effects of cannabis use on sleep outcomes did not survive multiple comparisons correction test (all p adj > 0.34), the adjusted p values for the main effects of cannabis behaviors/history on expectations of cannabis as a sleep aid (p adj = 0.07-0.09) and the main effects of CBD concentration on sleep duration (p adj = 0.08), as well as the interaction terms of CBD and age for that model (p adj = 0.07), were trending.

CONCLUSION

Cannabis users have increased expectations of cannabis being a sleep aid, but few associations existed between cannabis use and sleep outcomes. The two exceptions were endorsing any cannabis use and frequency of edible use. Additionally, age may be an important moderator of the potential positive influence CBD concentration can have on sleep.

Sleep-Related Cannabis Expectancy Questionnaire (SR-CEQ): Initial Development among College Students

A growing body of literature demonstrates that cannabis is commonly used to aid sleep. Consistent with social cognitive theory, there is a vast literature documenting the role of outcome expectancies in the initiation, progression, and maintenance of cannabis use. Despite the readily endorsed belief that cannabis will help improve sleep, sleep-related expectancies have not been included in widely used cannabis expectancy measures. This study aimed to develop and provide preliminary psychometric evaluation of the Sleep-Related Cannabis Expectancy Questionnaire (SR-CEQ). Cross-sectional data were drawn from N= 166 college students (M _age = 18.83 [SD = 1.06; range: 18-24], 34% male, 71% White). Students completed an online survey including demographics and the 12-item SR-CEQ. Exploratory Factor Analysis identified two factors representing Negative Sleep-Related Cannabis Expectancies and Positive Sleep-Related Cannabis Expectancies. Confirmatory Factor Analysis demonstrated adequate fit of the two-factor measurement model to observed data (SRMR = 0.08). Students endorsed greater positive (versus negative) sleep-related cannabis expectancies on average, and male students reported significantly greater negative expectancies (but not positive expectancies) compared to female students. The SR-CEQ is the first cannabis expectancy assessment tool specific to sleep-related cannabis outcomes. Ongoing psychometric validation of the SR-CEQ is needed to assess convergent/predictive validity and replicate findings among relevant clinical samples.

Cannabis use is associated with greater total sleep time in middle-aged and older adults with and without HIV: A preliminary report utilizing digital health technologies

Current literature on the effect of cannabis use on sleep quality is mixed, and few studies have used objectively-measured sleep measures or real-time sampling of cannabis use to examine this relationship. The prevalence of cannabis use among older adults and persons living with HIV has increased in recent years, and poor sleep quality is elevated in these populations as well. However, research examining cannabis-sleep relationships in these populations is lacking. Thus, we aimed to examine the relationship between daily cannabis use and subsequent objectively-measured sleep quality in middle-aged and older adults with and without HIV. In this pilot study, seventeen (11 HIV+, 6 HIV-) adults aged 50-70 who consumed cannabis completed four daily smartphone-based surveys for 14 days, in which they reported their cannabis use (yes/no) since the last survey. Participants also wore actigraphy watches during the 14-day period to objectively assess sleep quality (i.e., efficiency, total sleep time, and sleep fragmentation). In linear mixed-effects models, cannabis use was significantly associated with greater subsequent total sleep time (β=0.56; p=0.046). Cannabis use was not related to a change in sleep efficiency (β=1.50; p=0.46) nor sleep fragmentation (β=0.846, p=0.756) on days with cannabis use versus days without cannabis use. These preliminary results indicate cannabis use may have a positive effect on sleep duration in middle-aged and older adults. However, future studies with larger sample sizes that assess cannabis use in more detail (e.g., route of administration, dose, reason for use) are needed to further understand this relationship.

Blunted highs: Pharmacodynamic and behavioral models of cannabis tolerance

Acute exposure to cannabis comes with neurocognitive impairment, leading to increased risk of human error and injury. Evidence however indicates that such acute effects are less prominent in chronic users, suggesting cannabis tolerance. Models of cannabis tolerance stress the importance of neurobiological or behavioral adaptations following repeated cannabis exposure. The pharmacodynamic model relates neuroadaptive changes in the brain to a blunted response to cannabis. Downregulation of CB1 receptors in chronic cannabis users has been associated with a normalization of dopaminergic output from the ventral tegmental area to the mesolimbic circuit, and a reduction of impairment during acute cannabis exposure. Such neuroadaptions are absent in occasional users, who show strong increments of dopamine and glutamate levels in the striatum, a loss of functional connectivity within the mesolimbic circuit and neurocognitive impairments when exposed to cannabis. Evidence for a behavioral model of cannabis tolerance that poses that users can have volitional control to overcome functional impairment during cannabis intoxication is relatively weak, and at best shows limited control over a limited number of behavioral functions. Cannabis tolerance is most likely to occur in users that consume high doses of cannabis continuously, at a high pace, for a prolonged period of time. Knowledge on frequency, dose and duration of cannabis use that is needed to achieve, maintain or lessen tolerance however is very limited, but will be of importance in the context of cannabis therapeutics and in legal settings when evaluating the impact of cannabis exposure on human function.

Targeting the Endocannabinoid CB1 Receptor to Treat Body Weight Disorders: A Preclinical and Clinical Review of the Therapeutic Potential of Past and Present CB1 Drugs

Obesity rates are increasing worldwide and there is a need for novel therapeutic treatment options. The endocannabinoid system has been linked to homeostatic processes, including metabolism, food intake, and the regulation of body weight. Rimonabant, an inverse agonist for the cannabinoid CB1 receptor, was effective at producing weight loss in obese subjects. However, due to adverse psychiatric side effects, rimonabant was removed from the market. More recently, we reported an inverse relationship between cannabis use and BMI, which has now been duplicated by several groups. As those results may appear contradictory, we review here preclinical and clinical studies that have studied the impact on body weight of various cannabinoid CB1 drugs. Notably, we will review the impact of CB1 inverse agonists, agonists, partial agonists, and neutral antagonists. Those findings clearly point out the cannabinoid CB1 as a potential effective target for the treatment of obesity. Recent preclinical studies suggest that ligands targeting the CB1 may retain the therapeutic potential of rimonabant without the negative side effect profile. Such approaches should be tested in clinical trials for validation.

Is time elapsed between cannabis use and sleep start time associated with sleep continuity? An experience sampling method

BACKGROUND

A substantial proportion of people using cannabis report using it to improve sleep. Yet, little research exists on the associations between the timing of cannabis use and sleep. This study examines the time elapsed between cannabis use and sleep start time and its association with two of the main indicators of sleep continuity: (1) sleep onset latency (SOL) and (2) number of awakenings (NOA) throughout the night.

METHODS

Each morning, for 7 consecutive days, daily cannabis users (n = 54) reported on the timing of previous night's cannabis use and sleep indicators on their smartphones. Mixed effects models examined the relations of within- and between-subjects' time elapsed between previous night cannabis use and sleep start time, with (1) SOL and (2) NOA.

RESULTS

Within subjects, shorter time elapsed between cannabis use and sleep start time was associated with shorter SOL (β = 0.519, p = 0.010), but not NOA (β = -0.030, p = 0.535). Furthermore, between individuals, the time gap between the previous night cannabis use and sleep start time was not associated with SOL or NOA (p > 0.05).

CONCLUSIONS

It is possible that cannabis use proximal to bedtime is associated with shorted sleep onset latency but not nighttime awakenings. Cannabis users should be informed about both the potential sleep aid effects of cannabis and its limitations. Pending further evidence of the effects of cannabis on sleep, cannabis users experiencing sleep problems should be provided with evidence-based alternatives to improve sleep, e.g., pharmacological and behavioral treatments.

Exploring the munchies: An online survey of users' experiences of cannabis effects on appetite and the development of a Cannabinoid Eating Experience Questionnaire

BACKGROUND

Cannabis intoxication is commonly reported to increase appetite and enhance appreciation of food (the 'munchies'). These effects are attributed to activation of the endocannabinoid system. However, the psychological changes that underlie these phenomena are under-researched. We report here the results of an extensive online survey of cannabis users with an exploratory Cannabinoid Eating Experience Questionnaire (CEEQ).

METHOD

Frequent cannabis users completed a 46-item questionnaire about their eating behaviour under the influence of cannabis. An English-speaking sample (n=591) provided data for the initial exploratory validation of the scale. A second Dutch-language survey (n=163) was used for confirmatory factor analysis. Test-retest reliability was based on a third English-speaking sample (n=40) who completed the revised, 28-item CEEQ twice across 2 weeks.

RESULTS

Principal components analysis provided a two-factor solution. Factor 1 (hedonic) comprised 14 items that related primarily to the enjoyment and altered sensory aspects of eating. Factor 2 (appetitive) comprised a further 14 items related to motivational factors that instigate or promote eating. The two-factor structure was supported by confirmatory factor analysis. Both the hedonic and appetitive subscales had good internal reliability (α=0.92 for each subscale, in two independent samples). Good test-retest reliability was obtained for the revised 28-item questionnaire (ps<.01 for Total CEEQ and each subscale).

CONCLUSION

The Cannabinoid Eating Experience Questionnaire provided a valid, reliable assessment of the psychological features of cannabis-induced alterations to appetite. Our data confirm that cannabis principally influences the motivational factors that lead to the initiation of eating and the hedonic factors implicated in maintaining eating.

Medical Cannabis for the Treatment of Fibromyalgia

BACKGROUND

Fibromyalgia is a chronic pain syndrome, characterized by chronic musculoskeletal pain, fatigue, and mood disturbances. There are nearly no data on the effect of medical cannabis (MC) treatment on patients with fibromyalgia.

METHODS

Data were obtained from the registries of 2 hospitals in Israel (Laniado Hospital and Nazareth Hospital) on patients with a diagnosis of fibromyalgia who were treated with MC. After obtaining patient consent, demographic, clinical, and laboratory parameters were documented. All the patients also completed the Revised Fibromyalgia Impact Questionnaire regarding the period before and after MC treatment.

RESULTS

Thirty patients were identified, and 26 patients were included in the study. There were 19 female patients (73%), and the mean age of the study group was 37.8 ± 7.6 years. The mean dosage of MC was 26 ± 8.3 g per month, and the mean duration of MC use was 10.4 ± 11.3 months. After commencing MC treatment, all the patients reported a significant improvement in every parameter on the questionnaire, and 13 patients (50%) stopped taking any other medications for fibromyalgia. Eight patients (30%) experienced very mild adverse effects.

CONCLUSIONS

Medical cannabis treatment had a significant favorable effect on patients with fibromyalgia, with few adverse effects.

Medical Cannabinoids for Cancer Cachexia: A Systematic Review and Meta-Analysis

Objectives

Cancer cachexia (CCA) is an intractable and ineffective metabolic syndrome that attacks 50–80% of cancer patients. It reduces patient's life quality, affects the efficacy of treatment, and then increases their mortality; however, there are no established therapeutic strategies for CCA in the world. In this study, we assess the positive and negative effects of cannabinoid in the treatment of CCA.

Methods

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Web of Science, and PubMed up to December 2017.

Results

Of the 256 screened studies, three studies with a total of 592 participants were included. Compared with placebo, cannabinoid increased the appetite (MD 0.27, 95% CI -0.51 to 1.04; n= 3) but failed to improve the overall quality of life (QOL; MD -12.39, 95% CI [-24.21 to -0.57; n = 2), and a total of 441 patients had 607 adverse events (AEs; 496 in the cannabinoid group and 111 in the placebo group).

Conclusions

Our analysis showed cannabinoid is effective in increasing appetite in cancer patients. However, it declines the quality of life, which may be due to the side effects of cannabinoid.

Cannabis and alcohol use for sleep aid: A daily diary investigation

OBJECTIVE

One in 5 college students use substances such as cannabis and/or alcohol to help sleep. Despite this high prevalence of sleep aid use, there remains a lack of research on the potential day-to-day sleep- and substance-related consequences. The current study examined associations of cannabis and alcohol sleep aid use with subsequent sleep and substance use consequences among college students.

METHOD

Of a baseline sample of 217 college students endorsing past-month cannabis and/or alcohol use (1% cannabis only, 42% alcohol only, 58% both), 83 students endorsing past-month cannabis and/or alcohol use for sleep aid (M_age = 19.33 [SD = 1.11], 30% male, 72% White) completed online questionnaires for 14 consecutive days to report daily sleep, substance use, and negative substance consequences.

RESULTS

Multilevel models demonstrated that nights of cannabis sleep aid use predicted longer same-night sleep duration, shorter same-night wake time after sleep onset, and greater next-day daytime fatigue within person, after controlling for daily cannabis frequency. Alcohol sleep aid use was not associated with sleep-related outcomes or negative drinking consequences after controlling for daily alcohol quantity; these null results may be due to a low frequency of alcohol sleep aid use (1% of observations) over 14 days of assessment.

CONCLUSIONS

Results highlight daytime fatigue as a potential adverse short-term outcome of cannabis sleep aid use, despite its proximal sleep-related benefits. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Tolerance to WIN55,212-2 is delayed in desensitization-resistant S426A/S430A mice

Tolerance to cannabinoid agonists can develop through desensitization of the cannabinoid receptor 1 (CB1) following prolonged administration. Desensitization results from phosphorylation of CB1 by a G protein-coupled receptor kinase (GRK), and subsequent association of the receptor with arrestin. Mice expressing a mutant form of CB1, in which the serine residues at two putative phosphorylation sites necessary for desensitization have been replaced by non-phosphorylatable alanines (S426A/S430A), display reduced tolerance to Δ9-tetrahydrocannabinol (Δ9-THC). Tolerance to the antinociceptive effects of WIN55,212-2 was delayed in S426A/S430A mutants using the tail-flick and formalin tests. However, tolerance to the antinociceptive effects of once daily CP55,940 injections was not significantly delayed in S426A/S430A mutant mice using either of these tests. Interestingly, the dose response curve shifts for the hypothermic and antinociceptive effects of CP55,940 that were induced by chronic treatment with this agonist in wild-type mice were blocked in S426A/S430A mutant mice. Assessment of mechanical allodynia in mice exhibiting chronic cisplatin-evoked neuropathic pain found that tolerance to the anti-allodynic effects WIN55,212-2 but not CP55,940 was delayed in S426A/S430A mice compared to wild-type littermates. Despite these deficits in tolerance, S426A/S430A mutant mice eventually developed tolerance to both WIN55,212-2 and CP55,940 for all pain assays that were examined, suggesting that other mechanisms likely contribute to tolerance for these cannabinoid agonists. These findings suggest that GRK- and βarrestin2-mediated desensitization of CB1 may strongly contribute to the rate of tolerance to the antinociceptive effects of WIN55,212-2, and raises the possibility of agonist-specific mechanisms of cannabinoid tolerance.

Self-Medication for Sleep in College Students: Concurrent and Prospective Associations With Sleep and Alcohol Behavior

OBJECTIVE/BACKGROUND

College students are at an increased risk for poor sleep and associated sleep problems. Emerging evidence suggests that a substantial subset of college students self-medicate with alcohol, marijuana, or over-the-counter medications to help sleep. The current study identified demographic, psychosocial, and sleep- and alcohol-related correlates of self-medication for sleep, and assessed its concurrent and prospective associations with insomnia symptoms, alcohol drinking, and negative drinking consequences.

PARTICIPANTS

Undergraduate students (N = 171; mean age = 19 years [SD = 1.35], 32% male, 74% White) enrolled in a four-year university in the northeastern United States.

METHODS

Data were drawn from a short-term two-wave longitudinal study. Participants completed two online surveys, separated by an average interval of 68 days (SD = 10.22).

RESULTS

At Time 1, 25% of students reported using at least one substance (alcohol, marijuana, or over-the-counter medications) for sleep aid in the past two weeks. Male and older students were more likely to report using substances for sleep. Sleep aid use at Time 1 was concurrently associated with greater levels of alcohol frequency, negative drinking consequences, and insomnia symptoms. Further, sleep aid use at Time 1 was associated with an increase in negative drinking consequences from Time 1 to Time 2, but not with changes in alcohol frequency or insomnia symptoms.

CONCLUSIONS

These findings indicate that substances are widely used among college students for sleep aid. Sleep aid use is associated with greater concurrent drinking and insomnia symptoms, and increases in negative drinking consequences over a short time period.

New Prospect for Cancer Cachexia: Medical Cannabinoid

Cachexia is a common term for the wasting symptoms which may appear in almost every chronic illness, such as AIDS, tuberculosis, and cancer. Cancer cachexia (CCA) is a result of the interaction between the host and the tumor, mainly manifested in short-term wasting, malnutrition, and so on. Due to the chronic food shortages, absorption dysfunction and metabolic disorders, all of these eventually lead to hypoimmunity, organ failure, and higher susceptibility to pathogenic microorganisms. And then increased morbidity and mortality rates as well as reduced tolerance to anti-cancer treatments will be resulted in patients with CCA. Up to now, no standard guidelines have been established for cachexia treatment. Moreover, progestagens, the only drugs approved by FDA for cancer-related cachexia, can only increase adipose tissue and have not been confirmed to augment lean body mass. Cannabinoid, such as Δ-9-tetrahydrocannabinol (THC) and cannabidiol, is one of a class of diverse chemical compounds. Previous studies have showed that cannabinoid had considerable potential to improve the appetite, body weight, body fat level, caloric intake, mood, quality of life in kinds of diseases. This review will elaborate the anti-CCA role of cannabinoid and explore that whether cannabinoid is effective for CCA and provide a basis for guiding clinical drug use.

Endocannabinoids in Body Weight Control

Maintenance of body weight is fundamental to maintain one's health and to promote longevity. Nevertheless, it appears that the global obesity epidemic is still constantly increasing. Endocannabinoids (eCBs) are lipid messengers that are involved in overall body weight control by interfering with manifold central and peripheral regulatory circuits that orchestrate energy homeostasis. Initially, blocking of eCB signaling by first generation cannabinoid type 1 receptor (CB1) inverse agonists such as rimonabant revealed body weight-reducing effects in laboratory animals and men. Unfortunately, rimonabant also induced severe psychiatric side effects. At this point, it became clear that future cannabinoid research has to decipher more precisely the underlying central and peripheral mechanisms behind eCB-driven control of feeding behavior and whole body energy metabolism. Here, we will summarize the most recent advances in understanding how central eCBs interfere with circuits in the brain that control food intake and energy expenditure. Next, we will focus on how peripheral eCBs affect food digestion, nutrient transformation and energy expenditure by interfering with signaling cascades in the gastrointestinal tract, liver, pancreas, fat depots and endocrine glands. To finally outline the safe future potential of cannabinoids as medicines, our overall goal is to address the molecular, cellular and pharmacological logic behind central and peripheral eCB-mediated body weight control, and to figure out how these precise mechanistic insights are currently transferred into the development of next generation cannabinoid medicines displaying clearly improved safety profiles, such as significantly reduced side effects.

Dronabinol oral solution in the management of anorexia and weight loss in AIDS and cancer

The true incidence of anorexia secondary to human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) and cancer is not well classified owing to the fact that there is a lack of standardized definitions and recent clinical data in these settings. Dronabinol, or Δ-9-tetrahydrocannabinol, is a synthetic molecule that closely mimics the action of Cannabis sativa L., a naturally occurring compound activated in the central nervous system by cannabinoid receptors. Dronabinol exerts its effects by directly acting on the vomiting and appetite control centers in the brain, which in turn increases appetite and prevents vomiting. In the USA, dronabinol is currently available in two dosage formulations – oral capsule and oral solution. While the oral capsule was initially approved by the US Food and Drug Administration in 1985, the recent approval of the oral solution in 2016 presents an “easy-to-swallow” alternative for patients using or intending to use dronabinol. Dronabinol is indicated in adult patients with HIV/AIDS for the treatment of anorexia and weight loss. However, there is no approved indication in the setting of cancer-related anorexia and weight loss. This review aims at presenting available data on the use of oral dronabinol in the management of anorexia and weight loss in HIV/AIDS and cancer, as well as characterizing and highlighting the pharmacotherapeutic considerations of the newest formulation of dronabinol.

Systematic review and meta-analysis of cannabinoids in palliative medicine

We provide a systematic review and meta-analysis on the efficacy, tolerability, and safety of cannabinoids in palliative medicine. The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, PubMed, Scopus, and http://clinicaltrials.gov, and a selection of cancer journals were searched up until 15th of March 2017. Of the 108 screened studies, nine studies with a total of 1561 participants were included. Overall, the nine studies were at moderate risk of bias. The quality of evidence comparing cannabinoids with placebo was rated according to Grading of Recommendations Assessment, Development, and Evaluation as low or very low because of indirectness, imprecision, and potential reporting bias. In cancer patients, there were no significant differences between cannabinoids and placebo for improving caloric intake (standardized mean differences [SMD]: 0.2 95% confidence interval [CI]: [-0.66, 1.06] P = 0.65), appetite (SMD: 0.81 95% CI: [-1.14, 2.75]; P = 0.42), nausea/vomiting (SMD: 0.21 [-0.10, 0.52] P = 0.19), >30% decrease in pain (risk differences [RD]: 0.07 95% CI: [-0.01, 0.16]; P = 0.07), or sleep problems (SMD: -0.09 95% CI: [-0.62, 0.43] P = 0.72). In human immunodeficiency virus (HIV) patients, cannabinoids were superior to placebo for weight gain (SMD: 0.57 [0.22; 0.92]; P = 0.001) and appetite (SMD: 0.57 [0.11; 1.03]; P = 0.02) but not for nausea/vomiting (SMD: 0.20 [-0.15, 0.54]; P = 0.26). Regarding side effects in cancer patients, there were no differences between cannabinoids and placebo in symptoms of dizziness (RD: 0.03 [-0.02; 0.08]; P = 0.23) or poor mental health (RD: -0.01 [-0.04; 0.03]; P = 0.69), whereas in HIV patients, there was a significant increase in mental health symptoms (RD: 0.05 [0.00; 0.11]; P = 0.05). Tolerability (measured by the number of withdrawals because of adverse events) did not differ significantly in cancer (RD: 1.15 [0.80; 1.66]; P = 0.46) and HIV patients (RD: 1.87 [0.60; 5.84]; P = 0.28). Safety did not differ in cancer (RD: 1.12 [0.86; 1.46]; P = 0.39) or HIV patients (4.51 [0.54; 37.45]; P = 0.32) although there was large uncertainty about the latter reflected in the width of the CI. In one moderate quality study of 469 cancer patients with cancer-associated anorexia, megestrol was superior to cannabinoids in improving appetite, producing >10% weight gain and tolerability. In another study comparing megestrol to dronabinol in HIV patients, megestrol treatment led to higher weight gain without any differences in tolerability and safety. We found no convincing, unbiased, high quality evidence suggesting that cannabinoids are of value for anorexia or cachexia in cancer or HIV patients.

Are cannabinoids effective for HIV wasting syndrome?

INTRODUCTION

Wasting syndrome is a common problem in HIV. It leads to substantive morbidity and mortality. The use of cannabinoids has been suggested as a treatment for weight, but it is not clear whether they are really safe and effective.

METHODS

To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies and generated a summary of findings table using the GRADE approach.

RESULTS AND CONCLUSIONS

We identified eight systematic reviews including ten studies overall, of which six were randomized trials. We concluded it is not clear whether cannabinoids increase appetite or weight in HIV wasting syndrome because the certainty of the evidence is very low, and they probably lead to frequent adverse effects.

Effects of zolpidem alone and in combination with nabilone on cannabis withdrawal and a laboratory model of relapse in cannabis users

RATIONALE

Each year, over 300,000 individuals in the USA enter treatment for cannabis use disorder (CUD). The development of effective pharmacotherapy for CUD is a priority.

OBJECTIVE

This placebo-controlled study examined the effects of zolpidem alone and in combination with nabilone on cannabis withdrawal and a laboratory measure of relapse.

METHODS

Eleven daily, non-treatment-seeking cannabis users completed three, 8-day inpatient phases; each phase tested a different medication condition in counter-balanced order. On the first day of each phase, participants were administered placebo capsules t.i.d. and smoked experimenter-administered active cannabis (5.6 % Δ(9)-tetrahydrocannabinol (THC)). On days 2-8, the participants were administered capsules containing either placebo (0 mg at 0900, 1800, and 2300 hours), zolpidem (0 mg at 0900 and 1800, and 12.5 mg at 2300), or zolpidem (12.5 mg at 2300) and nabilone (3 mg at 0900 and 1800). Cannabis withdrawal, subjective capsule effects, and cognitive performance were examined on days 3-4, when only inactive cannabis (0.0 % THC) was available for self-administration. "Relapse" was measured on days 5-8, when participants could self-administer active cannabis.

RESULTS

Both medication conditions decreased withdrawal-related disruptions in sleep, but only zolpidem in combination with nabilone decreased withdrawal-related disruptions in mood and food intake relative to placebo. Zolpidem in combination with nabilone, but not zolpidem alone, decreased self-administration of active cannabis. Zolpidem in combination with nabilone also produced small increases in certain abuse-related subjective capsule ratings, while zolpidem alone did not. Neither medication condition altered cognitive performance.

CONCLUSIONS

Clinical testing of nabilone, either alone, or in combination with zolpidem is warranted.

Clinical utility of dronabinol in the treatment of weight loss associated with HIV and AIDS

Since the beginning of the HIV/AIDS epidemic, weight loss has been a common complaint for patients. The use of various definitions defining HIV wasting syndrome has made it difficult to determine its actual prevalence. Despite the use of highly active antiretroviral therapy, it is estimated that the prevalence of HIV wasting syndrome is between 14% and 38%. HIV wasting syndrome may stem from conditions affecting chewing, swallowing, or gastrointestinal motility, neurologic disease affecting food intake or the perception of hunger or ability to eat, psychiatric illness, food insecurity generated from psychosocial or economic concerns, or anorexia due to medications, malabsorption, infections, or tumors. Treatment of HIV wasting syndrome may be managed with appetite stimulants (megestrol acetate or dronabinol), anabolic agents (testosterone, testosterone analogs, or recombinant human growth hormone), or, rarely, cytokine production modulators (thalidomide). The goal of this review is to provide an in-depth evaluation based on existing clinical trials on the clinical utility of dronabinol in the treatment of weight loss associated with HIV/AIDS. Although total body weight gain varies with dronabinol use (–2.0 to 3.2 kg), dronabinol is a well-tolerated option to promote appetite stimulation. Further studies are needed with standardized definitions of HIV-associated weight loss and clinical outcomes, robust sample sizes, safety and efficacy data on chronic use of dronabinol beyond 52 weeks, and associated virologic and immunologic outcomes.

Naltrexone Maintenance Decreases Cannabis Self-Administration and Subjective Effects in Daily Cannabis Smokers

Given that cannabis use is increasing in the United States, pharmacological treatment options to treat cannabis use disorder are needed. Opioid antagonists modulate cannabinoid effects and may offer a potential approach to reducing cannabis use. In this double-blind, placebo-controlled human laboratory study, we assessed the effects of naltrexone maintenance on the reinforcing, subjective, psychomotor, and cardiovascular effects of active and inactive cannabis. Nontreatment-seeking, daily cannabis smokers were randomized to receive naltrexone (50 mg: n=18 M and 5 F) or placebo (0 mg; n=26 M and 2 F) capsules for 16 days. Before, during, and after medication maintenance, participants completed 10 laboratory sessions over 4-6 weeks, assessing cannabis' behavioral and cardiovascular effects. Medication compliance was verified by observed capsule administration, plasma naltrexone, and urinary riboflavin. Relative to placebo, maintenance on naltrexone significantly reduced both active cannabis self-administration and its positive subjective effects ('good effect'). Participants in the placebo group had 7.6 times (95% CI: 1.1-51.8) the odds of self-administering active cannabis compared with the naltrexone group. This attenuation of reinforcing and positive subjective effects also influenced cannabis use in the natural ecology. Naltrexone had intrinsic effects: decreasing ratings of friendliness, food intake, and systolic blood pressure, and increasing spontaneous reports of stomach upset and headache, yet dropout rates were comparable between groups. In summary, we show for the first time that maintenance on naltrexone decreased cannabis self-administration and ratings of 'good effect' in nontreatment-seeking daily cannabis smokers. Clinical studies in patients motivated to reduce their cannabis use are warranted to evaluate naltrexone's efficacy as a treatment for cannabis use disorder.

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

BACKGROUND

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

OBJECTIVE

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

CONCLUSION

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

An animal model of female adolescent cannabinoid exposure elicits a long-lasting deficit in presynaptic long-term plasticity

Cannabis continues to be the most accessible and popular illicit recreational drug. Whereas current data link adolescence cannabinoid exposure to increased risk for dependence on other drugs, depression, anxiety disorders and psychosis, the mechanism(s) underlying these adverse effects remains controversial. Here we show in a mouse model of female adolescent cannabinoid exposure deficient endocannabinoid (eCB)-mediated signaling and presynaptic forms of long-term depression at adult central glutamatergic synapses in the prefrontal cortex. Increasing endocannabinoid levels by blockade of monoacylglycerol lipase, the primary enzyme responsible for degrading the endocannabinoid 2-arachidonoylglycerol (2-AG), with the specific inhibitor JZL 184 ameliorates eCB-LTD deficits. The observed deficit in cortical presynaptic signaling may represent a neural maladaptation underlying network instability and abnormal cognitive functioning. Our study suggests that adolescent cannabinoid exposure may permanently impair brain functions, including the brain's intrinsic ability to appropriately adapt to external influences.

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

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

Marijuana and body weight

Acute marijuana use is classically associated with snacking behavior (colloquially referred to as "the munchies"). In support of these acute appetite-enhancing effects, several authorities report that marijuana may increase body mass index in patients suffering from human immunodeficiency virus and cancer. However, for these medical conditions, while appetite may be stimulated, some studies indicate that weight gain is not always clinically meaningful. In addition, in a study of cancer patients in which weight gain did occur, it was less than the comparator drug (megestrol). However, data generally suggest that acute marijuana use stimulates appetite, and that marijuana use may stimulate appetite in low-weight individuals. As for large epidemiological studies in the general population, findings consistently indicate that users of marijuana tend to have lower body mass indices than nonusers. While paradoxical and somewhat perplexing, these findings may be explained by various study confounds, such as potential differences between acute versus chronic marijuana use; the tendency for marijuana use to be associated with other types of drug use; and/or the possible competition between food and drugs for the same reward sites in the brain. Likewise, perhaps the effects of marijuana are a function of initial weight status-i.e., maybe marijuana is a metabolic regulatory substance that increases body weight in low-weight individuals but not in normal-weight or overweight individuals. Only further research will clarify the complex relationships between marijuana and body weight.

Mutation of putative GRK phosphorylation sites in the cannabinoid receptor 1 (CB1R) confers resistance to cannabinoid tolerance and hypersensitivity to cannabinoids in mice

For many G-protein-coupled receptors (GPCRs), including cannabinoid receptor 1 (CB1R), desensitization has been proposed as a principal mechanism driving initial tolerance to agonists. GPCR desensitization typically requires phosphorylation by a G-protein-coupled receptor kinase (GRK) and interaction of the phosphorylated receptor with an arrestin. In simple model systems, CB1R is desensitized by GRK phosphorylation at two serine residues (S426 and S430). However, the role of these serine residues in tolerance and dependence for cannabinoids in vivo was unclear. Therefore, we generated mice where S426 and S430 were mutated to nonphosphorylatable alanines (S426A/S430A). S426A/S430A mutant mice were more sensitive to acutely administered delta-9-tetrahydrocannabinol (Δ(9)-THC), have delayed tolerance to Δ(9)-THC, and showed increased dependence for Δ(9)-THC. S426A/S430A mutants also showed increased responses to elevated levels of endogenous cannabinoids. CB1R desensitization in the periaqueductal gray and spinal cord following 7 d of treatment with Δ(9)-THC was absent in S426A/S430A mutants. Δ(9)-THC-induced downregulation of CB1R in the spinal cord was also absent in S426A/S430A mutants. Cultured autaptic hippocampal neurons from S426A/S430A mice showed enhanced endocannabinoid-mediated depolarization-induced suppression of excitation (DSE) and reduced agonist-mediated desensitization of DSE. These results indicate that S426 and S430 play major roles in the acute response to, tolerance to, and dependence on cannabinoids. Additionally, S426A/S430A mice are a novel model for studying pathophysiological processes thought to involve excessive endocannabinoid signaling such as drug addiction and metabolic disease. These mice also validate the approach of mutating GRK phosphorylation sites involved in desensitization as a general means to confer exaggerated signaling to GPCRs in vivo.

Pharmacologic management of human immunodeficiency virus wasting syndrome

Pharmacologic interventions for human immunodeficiency virus (HIV) wasting have been studied since the 1990s, but the results of these interventions have been difficult to compare because the studies used different HIV wasting definitions and assessed various patient outcomes. Thus, we performed a systematic review of the current literature to identify studies that evaluated pharmacologic management of HIV wasting and to compare and contrast treatment options. Further, we provide a comprehensive review of these treatment options and describe the definition of HIV wasting used in each study, the outcomes assessed, and whether antiretroviral therapy was used during the HIV wasting treatment. Literature searches of the PubMed/Medline (1946-2014) and Google Scholar databases were performed, and a review of the bibliographies of retrieved articles was performed to identify additional references. Only English-language articles pertaining to humans and HIV-infected individuals were evaluated. Thirty-six studies were identified that assessed pharmacologic interventions to treat HIV wasting. Appetite stimulants, such as megestrol acetate, have been shown to increase total body weight (TBW) and body mass index in HIV-infected patients with wasting. Studies evaluating dronabinol showed conflicting data on TBW increases, but the drug may have minimal benefit on body composition compared with other appetite stimulants. Testosterone has been shown to be effective in HIV wasting for those who suffer from hypogonadism. Recombinant human growth hormone has been evaluated for HIV wasting and has shown promising results for TBW and lean body mass increases. Thalidomide has been studied; however, its use is limited due to its toxicities. Although megestrol acetate and dronabinol are approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV wasting, it is important to recognize other comorbidities such as depression or hypogonadism that may contribute to the patient's appetite and weight loss. If a patient is diagnosed with hypogonadism and HIV wasting, testosterone would be a good therapeutic option. Although mirtazapine is not FDA approved for the management of HIV wasting, it has been shown to promote weight gain while treating depression symptoms. Mirtazapine may be a promising pharmacologic option in the management of HIV wasting and depression, but further research is needed.

Dronabinol in severe, enduring anorexia nervosa: a randomized controlled trial

OBJECTIVE

The evidence for pharmacological treatment of severe, longstanding anorexia nervosa (AN) is sparse and the few controlled pharmacologic studies have focused on a narrow range of drugs. The aim of the present study was to investigate the effects of treatment with a synthetic cannabinoid agonist on body weight and eating disorder-related psychopathological personality traits in women with severe, enduring AN.

METHOD

This add-on, prospective, randomized, double blind, controlled crossover study was conducted between 2008 and 2011 at a specialized care center for eating disorders. Twenty-five women over 18 years with AN of at least 5 years duration were randomized to treatment with either dronabinol-placebo or placebo-dronabinol. In addition to the standardized baseline therapeutic regime, the participants received dronabinol, 2.5 mg twice daily for 4 weeks and matching placebo for 4 weeks, separated by a 4-week wash-out period. Primary outcome was the mean change in body weight. Secondary outcome was score changes on the Eating Disorder Inventory-2 (EDI-2). Data were analyzed for the 24 patients who completed the trial.

RESULTS

During dronabinol treatment, participants gained 0.73 kg (t = 2.86, df = 22, p < 0.01) above placebo without significant psychotropic adverse events. Dronabinol significantly predicted weight gain in a multiple linear regression including EDI-2 body dissatisfaction score and leptin. EDI-2 subscale scores showed no significant changes over time.

DISCUSSION

Dronabinol therapy was well tolerated. During four weeks of exposure it induced a small but significant weight gain in the absence of severe adverse events.

Subjective, cognitive and cardiovascular dose-effect profile of nabilone and dronabinol in marijuana smokers

Marijuana dependence is a substantial public health problem, with existing treatments showing limited efficacy. In laboratory and clinical studies, the cannabinoid receptor 1 agonist oral Δ9tetrahydrocannabinol (THC; dronabinol) has been shown to decrease marijuana withdrawal but not relapse. Dronabinol has poor bioavailability, potentially contributing to its failure to decrease relapse. The synthetic THC analogue, nabilone, has better bioavailability than dronabinol. We therefore aimed to characterize nabilone's behavioral and physiological effects across a range of acute doses in current marijuana smokers and compare these with dronabinol's effects. Participants (4 female; 10 male) smoking marijuana 6.6 (standard deviation = 0.7) days/week completed this outpatient, within-subjects, double-blind, randomized protocol. Over seven sessions, the time-dependent subjective, cognitive and cardiovascular effects of nabilone (2, 4, 6, 8 mg), dronabinol (10, 20 mg) and placebo were assessed. Nabilone (4, 6, 8 mg) and dronabinol (10, 20 mg) increased ratings of feeling a good effect, a strong effect and/or 'high' relative to placebo; nabilone had a slower onset of peak subjective effects than dronabinol. Nabilone (6, 8 mg) modestly lowered psychomotor speed relative to placebo and dronabinol. There were dose-dependent increases in heart rate after nabilone, and nabilone (2 mg) and dronabinol (10 mg) decreased systolic blood pressure. Thus, nabilone produced sustained, dose-related increases in positive mood, few cognitive decrements and lawful cardiovascular alterations. It had a longer time to peak effects than dronabinol, and effects were more dose-related, suggesting improved bioavailability. Nabilone was well tolerated by marijuana smokers, supporting further testing as a potential medication for marijuana dependence.