Adverse effects of heavy cannabis use: even plants can harm the brain

Emergency Department Patients Presenting after Oral versus Inhaled Cannabinoid use: A Retrospective Analysis

INTRODUCTION

Cannabinoid-related emergency department (ED) visits are increasing, yet little has been published about how the route of cannabinoid use (inhaled versus oral) affects ED presentations. We sought to compare ED visits from inhaled versus oral cannabinoid use.

METHODS

We performed a retrospective cohort study using ED patients with a cannabinoid related diagnosis from January 1, 2020 and May 31, 2023 from a single hospital system in Florida. We performed manual chart review to categorize visits into "unlikely", "possibly", or "highly likely" to be due to acute cannabinoid use. For our primary analysis, we used the "highly likely" group to compare the presentations and outcomes of patients who had used oral cannabinoids versus inhaled. Our primary outcome was hospital admission.

RESULTS

We deemed 303 patient visits "highly likely" to be from acute cannabinoids: 59 (19.5%) inhaled and 244 (80.5%) oral. Zero patients in the inhaled group were admitted compared to 15 (6.2%) in the oral group, a difference of 6.2% (95% CI 3.1-9.2%), p = 0.05. Additionally, 65 (26.7%) of the oral group reported using cannabinoids unintentionally including 8 housekeepers who ate food products left by hotel guests. Comparatively, 4 (6.8%) of the inhaled group unintentionally used cannabinoids (difference 19.9% [95% CI 11.4-28.3]).

CONCLUSIONS

Most patients who presented to the ED for the effects of acute cannabinoids had used them orally. Compared to patients who had inhaled cannabinoids, those who used them orally required more ED diagnostic resources and were more likely to be admitted to the hospital for additional evaluation or treatment. From a public health perspective, increased regulation of edible cannabinoid products may be needed.

The Intoxication Equivalency of 11-Hydroxy-Δ9-Tetrahydrocannabinol Relative to Δ9-Tetrahydrocannabinol

Δ9-Tetrahydrocannabinol (THC) is a psychoactive phytocannabinoid found in the Cannabis sativa plant. THC is primarily metabolized into 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (COOH-THC), which may themselves be psychoactive. There is very little research-based evidence concerning the pharmacokinetics and pharmacodynamics of 11-OH-THC as an individual compound. Male C57BL/6 mice were treated with THC or 11-OH-THC via intraperitoneal injection, tail vein intravenous injection, or oral gavage, and whole-blood compound levels were measured to determine pharmacokinetic parameters [Cmax, time to Cmax (Tmax), elimination half-life, area under the curve, apparent volume of distribution, systemic clearance, terminal rate constant, and absolute bioavailability] while also monitoring changes in catalepsy, body temperature, and nociception. 11-OH-THC achieved a Tmax at 30 minutes for all routes of administration. The maximum concentration at 30 minutes was not different between intravenous and intraperitoneal routes, but the oral gavage Cmax was significantly lower. THC had a 10-minute time to the maximum concentration, which was the first blood collection time point, for intravenous and intraperitoneal and 60 minutes for oral gavage, with a lower Cmax for intraperitoneal and oral gavage compared with intravenous. When accounting for circulating compound levels and ED50 responses, these data suggest that 11-OH-THC was 153% as active as THC in the tail-flick test of nociception and 78% as active as THC for catalepsy. Therefore, 11-OH-THC displayed equal or greater activity than the parent compound THC, even when accounting for pharmacokinetic differences. Thus, the THC metabolite 11-OH-THC likely plays a critical role in the bioactivity of cannabis; understanding its activity when administered directly will aid in the interpretation of future animal and human studies. SIGNIFICANCE STATEMENT: This study establishes that the primary metabolite of THC, 11-OH-THC, displays equal or greater activity than THC in a mouse model of cannabinoid activity when directly administered and even when accounting for route of administration, sex, pharmacokinetic, and pharmacodynamic differences. These data provide critical insight into the bioactivity of THC metabolites that will inform the interpretation of future in vivo cannabinoid research and represent a model for how THC consumption and metabolism may affect cannabis use in humans.

The Role of Cannabis in the Development of Psychosis

Cannabis is known to cause psychotic disorders, and the increasing use of cannabis constitutes an important health problem. Growing evidence that cannabis causes the development of psychosis has led to an increase in the number of studies in this field. This review aims to clarify the role of cannabis use in the development of psychosis, discuss the current literature about the underlying neurobiological mechanisms. For this purpose PubMed was searched for the keywords "cannabis use, psychosis, schizophrenia, endocannabinoid system, pathophysiology, neurobiology"; the articles published in the last 10 years were reviewed. Epidemiological studies showed that cannabis use starting at an earlier age is associated with an increased risk of psychosis, this risk is more pronounced in people with genetic predisposition and increases with heavy and high potency cannabis use. Studies showed that the endocannabinoid system, which plays a role in nervous system development and functions as a homeostatic regulator in physiological processes, is affected by cannabis use during critical periods of development like adolescence; cannabis use affects physiological processes such as synaptic pruning due to the effects of this system on neurotransmitters like glutamate and dopamine leading to long-term behavioral and psychological consequences. Additionally, evidence that dysfunctions in the endocannabinoid system play a role in the etiology of schizophrenia suggests that cannabis affects the disease process by worsening existing dysfunctions in this system. Understanding the relationship between cannabis use and the development of psychosis and underlying neurobiological mechanisms will help to identify new treatment targets, and develop appropriate preventive approaches. Keywords: Cannabis Abuse, Psychotic Disorders, Schizophrenia, Endocannabinoids, Neurobiology.

Adolescent Cannabis Use, Comorbid Attention-Deficit/Hyperactivity Disorder, and Other Internalizing and Externalizing Disorders

Cannabis use often co-occurs with attention-deficit/hyperactivity disorder and other internalizing and externalizing disorders. Treatment planning, including pharmacologic and psychosocial interventions, for these comorbid disorders require thorough diagnostic evaluation to determine the extent of social, emotional, and behavioral impairments, severity of substance use, and motivation for change. Improved understanding of these comorbid disorders will inform treatment planning that address current symptoms and behaviors and may also prevent the development of mental health and substance use disorders in early adulthood.

Experiences and Perceptions of Medical Cannabis among People Living with Chronic Pain and Community Pharmacists: A Qualitative Study in Canada

Background

The use of cannabis to treat chronic pain is under debate despite high expectations from patients. Qualitative data obtained by exploring both patients' and health professionals' perspectives are scarce.

Aims

This study aimed to understand the experiences and perceptions of people living with chronic pain and community pharmacists regarding the role of cannabis in chronic pain treatment in the Canadian context where both medical and recreational cannabis are legal.

Methods

We conducted 12 online focus groups (July 2020-February 2021) with 26 patients and 19 community pharmacists using semistructured discussion guides. All discussions were audio recorded and transcribed verbatim were analyzed using a reflexive thematic approach.

Results

We developed three themes related to patients' perspectives and three themes related to pharmacists' perspectives. Patients' perspectives included (1) cannabis as an alternative to other pain medications, (2) a new treatment with potential health-related risks, and (3) a therapy rather than a recreational drug. Pharmacists' perspectives included (1) challenges in monitoring drug interactions with cannabis in the context of scarce research data, (2) informing and treating patients self-medicating with cannabis amid its growing popularity, and (3) financial costs and legal constraints for patients.

Conclusions

This study highlights patients' and pharmacists' urgent need for reliable information regarding the benefits and risks of cannabis. Training tailored to pharmacists' needs and evidence-based information for patients should be developed to support pharmacists' practice, improve patients' experiences, and promote safe cannabis use.

Ecological Momentary Assessment of Cannabis Use and Affect Among Adolescents Following Psychiatric Discharge

OBJECTIVE

Affect regulation is central to multiple theoretical models that explain cannabis use (CU) behavior. However, much of the research has been conducted with adults, leaving unanswered questions about the nature of associations among adolescents, especially those with affective disorders. Using clinical interviews and ecological momentary assessment (EMA), we assessed rates of adolescent CU and momentary associations with affect following psychiatric discharge among youth hospitalized for suicidal thoughts and behaviors.

METHOD

Participants were 13- to 18-year-olds (N = 62; 64.5% female) recruited from an inpatient psychiatric hospital who reported having ever used cannabis. Participants completed clinical interviews during hospitalization. EMA was conducted for 21 days upon discharge.

RESULTS

Concurrent use of other drugs was associated with greater odds of CU (odds ratio = 27.63). Momentary CU was associated with higher levels of positive affect and lower levels of anger/irritability, but not with negative affect. The effect of momentary CU on positive affect was greater among youth with a diagnosis of posttraumatic stress disorder (PTSD) or generalized anxiety disorder (GAD).

CONCLUSIONS

Findings suggest that adolescents may use cannabis to enhance positive emotion, especially those with PTSD/GAD. Results highlight the importance of tailored interventions that focus on providing alternative and adaptive methods to enhance positive affect.

Pain Management Strategies After Orthopaedic Trauma: A Mixed-Methods Study with a View to Optimizing Practices

PURPOSE

To examine 1) pain management strategies within the care trajectory of orthopaedic trauma patients and patients' perception of their effectiveness, 2) adverse effects (AEs) associated with pharmacological treatments, particularly opioids and cannabis, and 3) patients' perceptions of strategies that should be applied after an orthopaedic trauma and support that they should obtain from health professionals for their use.

PATIENTS AND METHODS

This study was conducted with orthopaedic trauma patients in a level 1 trauma center. A convergent mixed-methods design was used. Data on pain experience, pain management strategies used and AEs were collected with self-administered questionnaires at hospital discharge (T1) and at 3 months after injury (T2). Patients' preferences about the pain management strategies used, the required support and AEs were further examined through semi-structured individual interviews at the same time measures. Descriptive statistics and thematic analyses were performed.

RESULTS

Seventy-one patients were recruited and 30 individual interviews were undertaken. Pharmacological pain management strategies used at T1 and T2 were mainly opioids (95.8%; 20.8%) and acetaminophen (91.5%; 37.5%). The most frequently applied non-pharmacological strategies were sleep (95.6%) and physical positioning (89.7%) at T1 and massage (46.3%) and relaxation (32.5%) at T2. Findings from quantitative and qualitative analyses highlighted that non-pharmacological strategies, such as comfort, massage, distraction, and physical therapy, were perceived as the most effective by participants. Most common AEs related to opioids were dry mouth (78.8%) and fatigue (66.1%) at T1 and insomnia (30.0%) and fatigue (20.0%) at T2. Dry mouth (28.6%) and drowsiness (14.3%) were the most reported AEs by patients using recreational cannabis. An important need for information at hospital discharge and for a personalized follow-up was identified by participants during interviews.

CONCLUSION

Despite its AEs, we found that opioids are still the leading pain management strategy after an orthopaedic trauma and that more efforts are needed to implement non-pharmacological strategies. Cannabis was taken for recreational purposes but patients also used it for pain relief. Support from health professionals is needed to promote the adequate use of these strategies.

Considerations for Cannabinoids in Perioperative Care by Anesthesiologists

Increased usage of recreational and medically indicated cannabinoid compounds has been an undeniable reality for anesthesiologists in recent years. These compounds’ complicated pharmacology, composition, and biological effects result in challenging issues for anesthesiologists during different phases of perioperative care. Here, we review the existing formulation of cannabinoids and their biological activity to put them into the context of the anesthesia plan execution. Perioperative considerations should include a way to gauge the patient’s intake of cannabinoids, the ability to gain consent properly, and vigilance to the increased risk of pulmonary and airway problems. Intraoperative management in individuals with cannabinoid use is complicated by the effects cannabinoids have on general anesthetics and depth of anesthesia monitoring while simultaneously increasing the potential occurrence of intraoperative hemodynamic instability. Postoperative planning should involve higher vigilance to the risk of postoperative strokes and acute coronary syndromes. However, most of the data are not up to date, rending definite conclusions on the importance of perioperative cannabinoid intake on anesthesia management difficult.

Systematic review and meta-analysis of cannabinoids, cannabis-based medicines, and endocannabinoid system modulators tested for antinociceptive effects in animal models of injury-related or pathological persistent pain

ABSTRACT

We report a systematic review and meta-analysis of studies that assessed the antinociceptive efficacy of cannabinoids, cannabis-based medicines, and endocannabinoid system modulators on pain-associated behavioural outcomes in animal models of pathological or injury-related persistent pain. In April 2019, we systematically searched 3 online databases and used crowd science and machine learning to identify studies for inclusion. We calculated a standardised mean difference effect size for each comparison and performed a random-effects meta-analysis. We assessed the impact of study design characteristics and reporting of mitigations to reduce the risk of bias. We meta-analysed 374 studies in which 171 interventions were assessed for antinociceptive efficacy in rodent models of pathological or injury-related pain. Most experiments were conducted in male animals (86%). Antinociceptive efficacy was most frequently measured by attenuation of hypersensitivity to evoked limb withdrawal. Selective cannabinoid type 1, cannabinoid type 2, nonselective cannabinoid receptor agonists (including delta-9-tetrahydrocannabinol) and peroxisome proliferator-activated receptor-alpha agonists (predominantly palmitoylethanolamide) significantly attenuated pain-associated behaviours in a broad range of inflammatory and neuropathic pain models. Fatty acid amide hydrolase inhibitors, monoacylglycerol lipase inhibitors, and cannabidiol significantly attenuated pain-associated behaviours in neuropathic pain models but yielded mixed results in inflammatory pain models. The reporting of criteria to reduce the risk of bias was low; therefore, the studies have an unclear risk of bias. The value of future studies could be enhanced by improving the reporting of methodological criteria, the clinical relevance of the models, and behavioural assessments. Notwithstanding, the evidence supports the hypothesis of cannabinoid-induced analgesia.