Intrahepatic cholestasis following abuse of powdered kratom (Mitragyna speciosa)

Psychoactive plant derivatives (ayahuasca, ibogaine, kratom) and their application in opioid withdrawal and use disorder - a narrative review

The opioid epidemic and limited access to treatment for opioid withdrawal (OW) and opioid use disorder (OUD) has led individuals to seek alternative treatments. This narrative review aims to educate clinicians on the mechanisms of action, toxicity, and applications of psychoactive plant-based substances patients may be using to self-treat OUD and OW. We specifically discuss ayahuasca, ibogaine, and kratom as they have the most evidence for applications in OUD and OW from the last decade (2012-2022). Evidence suggests these substances may have efficacy in treating OW and OUD through several therapeutic mechanisms including their unique pharmacodynamic effects, rituals performed around ingestion, and increased neuroplasticity. The current evidence for their therapeutic application in OUD and OW is primarily based on small observational studies or animal studies. High-quality, longitudinal studies are needed to clarify safety and efficacy of these substances in treatment of OW and OUD.

A review on Mitragyna speciosa (Rubiaceae) as a prominent medicinal plant based on ethnobotany, phytochemistry and pharmacological activities

Mitragyna speciosa Korth (kratom) is a tropical indigenous tree of Southeast Asia. It is commonly consumed by the people due to its various pharmacological properties. The leaves of this plant are traditionally used for the treatment of several diseases including pain, fever, cough, anxiety, depression, obesity, diarrhoea, wound healing, diabetes, hypertension as well as for the prevention of cancer and improvement of sexual performance. Phytochemical investigations have confirmed the presence of more than forty alkaloids along with the presence of other bioactive secondary metabolites. Among the alkaloids isolated, mitragynine and 7-hydroxymitragynine along with their derivatives have been widely evaluated and reported to possess various pharmacological effects. Hence, the aim of this review is to shed light on the traditional uses of kratom and the scientific studies to justify the folkloric claims and active principles responsible for the various medicinal effects associated with the leaves of this plant. This review highlights the potential benefits and toxicities associated with M. speciosa leaves along with the phytochemistry. Moreover, the existing gaps in the field of M. speciosa study have been identified along with the future directions to further avail the benefits of this plant species.

An insight review on the neuropharmacological effects, mechanisms of action, pharmacokinetics and toxicity of mitragynine

Mitragynine is one of the main psychoactive alkaloids in Mitragyna speciosa Korth. (kratom). It has opium-like effects by acting on μ-, δ-, and κ-opioid receptors in the brain. The compound also interacts with other receptors, such as adrenergic and serotonergic receptors and neuronal Ca2+ channels in the central nervous system to have its neuropharmacological effects. Mitragynine has the potential to treat diseases related to neurodegeneration such as Alzheimer's disease and Parkinson's disease, as its modulation on the opioid receptors has been reported extensively. This review aimed to provide an up-to-date and critical overview on the neuropharmacological effects, mechanisms of action, pharmacokinetics and safety of mitragynine as a prospective psychotropic agent. Its multiple neuropharmacological effects on the brain include antinociceptive, anti-inflammatory, antidepressant, sedative, stimulant, cognitive, and anxiolytic activities. The potential of mitragynine to manage opioid withdrawal symptoms related to opioid dependence, its pharmacokinetics and toxic effects were also discussed. The interaction of mitragynine with various receptors in the brain produce diverse neuropharmacological effects, which have beneficial properties in neurological disorders. However, further studies need to be carried out on mitragynine to uncover its complex mechanisms of action, pharmacokinetics, pharmacodynamic profiles, addictive potential, and safe dosage to prevent harmful side effects.

Endogenous Opioid Activity as the Mechanism of Action for Mitragyna speciosa (Kratom): The Current State of the Evidence

Kratom (Mitragyna speciosa) is a substance derived from botanical compounds native to Southeast Asia. This substance has been cultivated predominantly in Thailand, Malaysia, Vietnam, and Myanmar, where it has historically been used in traditional medicine as a near panacea for several health problems. Such ritualistic use of kratom has been present for centuries; however, recreational use appears to have increased globally, especially in the United States. Pharmacodynamic and pharmacokinetic studies have found that kratom demonstrates a unique parabolic, dose-dependent pattern of effects ranging from stimulation to opioid and analgesic effects. Pharmacological research indicates that kratom is both a mu opioid receptor (μ-OR; MOR) and a kappa opioid receptor (κ-OR; KOR) agonist, which mediates its analgesic effects. Other research suggests that kratom may simultaneously act on dopaminergic and serotonergic receptors, which mediate its stimulant effects. This chapter reviews the literature related to the structural, functional, and cultural characteristics of kratom use. We begin with an overview of current and historical patterns of kratom, followed by a review of data on the pharmacodynamics and pharmacokinetics of kratom thus far.

Kratom use disorder: case reports on successful treatment with home induction of buprenorphine-naloxone

BACKGROUND

Kratom has been used for different reasons such as pain, opioid withdrawal, and relaxation. Kratom can cause dependence and overdose, and it's classified under 'drugs of concern' by the US Drug Enforcement Administration. Despite these concerns, kratom is legal in most of the United States and many countries around the world with easy accessibility. Literature searches reveal recommendations to use buprenorphine (or buprenorphine-naloxone), which are medications to treat opioid use disorder, in order to treat patients with kratom use disorder; however, there are no formal guidelines available. Buprenorphine (or buprenorphine-naloxone) induction is recommended to be conducted under observation (i.e. in the clinic) in the United States, but COVID-19 has resulted in shifts toward telehealth.

OBJECTIVES

Describe case series of successful management of kratom use disorder using telehealth followed by unobserved buprenorphine-naloxone home induction and highlight implications for future management, including maintenance dosage and induction method.

METHODS

We present 2 very similar kratom use disorder patients who reported taking 35 g of kratom per day who underwent unobserved buprenorphine-naloxone home induction.

RESULTS

Both were seen via telehealth initially. They reported no adverse effects before, during, or after the unobserved home induction on buprenorphine-naloxone but stabilized on significantly different dosages.

CONCLUSION

Telehealth followed by unobserved buprenorphine-naloxone induction at home may be an alternative to traditional buprenorphine-naloxone induction where treatment accessibility is limited. In addition to daily doses of kratom use, other factors, such as duration of kratom use and individual psychological factors may determine the most comfortable dose of buprenorphine-naloxone.

Kratom use and mental health: A systematic literature review and case example

OBJECTIVE

This review aims to synthesize and critically evaluate the existing literature on kratom use and its possible association with induction of psychotic and manic symptoms, in order to identify potential areas for future research that would improve our understanding of the risks of kratom consumption.

METHODS

An electronic search was performed using five major databases: including PubMed, Scopus, Google Scholar, Web of Science, and PsycINFO. keywords such as kratom, Mitragyna speciosa, mania, psychosis, bipolar disorder, schizophrenia, schizoaffective, case report, and case series. The retrieved articles on initial search were screened based on predefined inclusion and exclusion criteria for this study, and then data synthesis was performed to analyze relevant information from the included studies.

RESULTS

Six prior papers were found using (1 case series and 5 case reports). These included 10 cases, involving kratom use association with mania and psychosis. The ages of patients ranged from 28 to 55 years mean age was 38, and (SD 13.74), the majority were males (8 out of 11). Patients had durations of kratom use ranging from 2 wk to 15 years. Significant association was found between kratom use and the worsening of psychotic and manic symptoms in individuals with psychiatric conditions.

CONCLUSIONS

Our research highlights the possibility of worsening preexisting psychiatric conditions in the context of kratom use. This study emphasizes the need for clinical evaluation of patients for kratom use. Additional research is required to gain a deeper understanding of the potential mental health implications of kratom use, especially among vulnerable populations.

[Kratom (Mitragyna Speciosa): a Psychoactive Plant with Opportunities and Risks]

Kratom is an evergreen tree that is native to Southeast Asia. Its leafs are traditionally used as a stimulant, a remedy for various health problems and for religious purposes. Especially in the US (in a lesser extent also in Europe) kratom use is significantly prevalent. In Western countries, kratom is used predominantly as an analgesic and stimulant, for the treatment of opioid use disorders, and for improving mental health (e. g., in depression, anxiety disorders). Main molecular constituents of kratom are alkaloids of which mitragynine and 7-hydroxymitragynine appear to be most important. Pharmacodynamics and -kinetics of kratom are complex and insufficiently studied. It is known that mitragynine and 7-hydroxymitragynine are partial agonist at human μ-opioid receptors and antagonists at κ- and δ-opioid receptors with additional effects at other central receptors. Tolerability of kratom is presumably better than that of classical opioids; this is probably due to missing effects of kratom on β-arrestin and discussed as a starting point for the development of opioids with improved tolerability. Some alkaloids of kratom are inhibitors of CYP26 and to a somewhat lesser degree of CYP2C19 and CYP3A4. The addictive potential of kratom appears to be lower than that of classical opioids; however, corresponding data is limited and kratom use disorders appear to occur primarily in Western countries. Several cases of severe health-related problems and deaths are known in the US; in these cases, however, polysubstance use was usually present. Kratom use is likely associated with hepatotoxicity and cardiotoxicity. Kratom-associated mortality and morbidity in Western countries are quantitatively significantly different from Southeast Asia, where kratom use is no public health problem. The reasons for this may be the combined use of substances (which is more prevalent in Western countries), higher dosages of consumed kratom, adulterations and contaminations of commercially available kratom in Western countries, pharmacokinetic interactions, and higher concentrations of 7-hydroxymitragynine in dried kratom leafs (that are typically consumed in Western countries) in comparison to fresh leafs (that are typically consumed in Southeast Asia).

A Critical Review of the Neuropharmacological Effects of Kratom: An Insight from the Functional Array of Identified Natural Compounds

Kratom (Mitragyna speciosa Korth. Havil) has been considered a narcotic drug for years, barred by the law in many parts of the world, while extensive research over the past few decades proves its several beneficial effects, some of which are still in ambiguity. In many countries, including Thailand, the indiscriminate use and abuse of kratom have led to the loss of life. Nonetheless, researchers have isolated almost fifty pure compounds from kratom, most of which are alkaloids. The most prevalent compounds, mitragynine and 7-hydroxy mitragynine, are reported to display agonist morphine-like effects on human μ-opioid receptors and antagonists at κ- and δ-opioid receptors with multimodal effects at other central receptors. Mitragynine is also credited to be one of the modulatory molecules for the Keap1-Nrf2 pathway and SOD, CAT, GST, and associated genes' upregulatory cascades, leading it to play a pivotal role in neuroprotective actions while evidently causing neuronal disorders at high doses. Additionally, its anti-inflammatory, antioxidative, antibacterial, and gastroprotective effects are well-cited. In this context, this review focuses on the research gap to resolve ambiguities about the neuronal effects of kratom and demonstrate its prospects as a therapeutic target for neurological disorders associated with other pharmacological effects.

Patterns of polysubstance use among adults in Malaysia-A latent class analysis

INTRODUCTION

Polysubstance use is the use of more than one non-prescribed licit or illicit substance at one time. This is a common phenomenon, but little is known about the severity and the various substances used by adults in Malaysia.

OBJECTIVE

To determine the pattern of polysubstance use and its associated factors among general adults in Malaysia.

METHODOLOGY

This was a secondary data analysis from the National Health and Morbidity Survey (NHMS) 2019), a cross-sectional population survey with a two-stage stratified random sampling design. A total of 10,472 Malaysians aged 18 years and above participated in this survey. Polysubstance use was defined as concurrent use of more than one substance, either alcohol, tobacco, or drugs (opioids, marijuana, amphetamine/ methamphetamine or kratom). A latent class analysis (LCA) was used to identify the membership of polysubstance groups. The association of class membership with demographic profiles was examined using Multinomial Logistic Regression analysis.

RESULTS

Fit indices (AIC = 16458.9, BIC = 16443.6) from LCA supported 3 classes solution: Class 1; "moderate-drug" group primarily combination used of tobacco and alcohol (2.4%), Class 2; "high-drug" group using multiple substance including kratom (0.3%) and Class 3; "low-drug" group reporting minimal alcohol and tobacco use or non-user (97.3%). The multinomial model showed young adults (18-40 years) had a higher likelihood of being polysubstance users both for moderate-drug class (OR = 4.1) and high-drug class (OR = 3.9) compared to older age (≥60 years). Chinese (OR = 18.9), Indian (OR = 23.3), Indigenous Sabah & Sarawak (OR = 34.6) and others ethnicity (OR = 8.9) showed higher odds of being moderate-drug users than Malays. The greater odds of moderate-drug use for males (OR = 35.5), working groups (OR = 1.5) and low education level group (OR = 3.2).

CONCLUSION

Our study highlights patterns and demographics related to the use of polysubstances among adults in Malaysia. These results would help formulate specific prevention programmes for these high-risk groups.

Controversial usages of kratom (Mitragyna speciosa): For good or for evil

Kratom (Mitragyna speciosa) is a plant that grows well in tropical climates such as in Southeast Asia. Traditionally, people discovered it possessed a stimulating effect that relieved tiredness. Furthermore, it contains analgesic and medicinal properties for the treatment of pain, diarrhea, muscle discomfort, and blood pressure and to enhance stamina. Nevertheless, long term or regular consumption of kratom leads to addiction. This is because the main alkaloid of kratom, mitragynine, binds to opioid receptors and exerts a euphoric effect similar to that of morphine, which may lead to death. Due to this reason, kratom has been listed as a regulated substance in many countries including the United States, Thailand, Malaysia, Bhutan, Finland, Lithuania, Denmark, Poland, Sweden, Australia, and Myanmar. Usages of kratom carry two pharmacological effects depending on dosage. Low-dose kratom exerts a stimulating effect that refreshes the user. High-dose kratom exerts sedative effects that can lead to addiction similar to that of morphine. Despite the euphoric effect of kratom, the beneficial values of kratom to human health is indisputable. Therefore, a complete banning of kratom may cause a loss to pharmaceutical industry. Rather, a controlled or selective usage of kratom will be a better choice.

Current and emerging pharmacotherapies for opioid dependence treatments in adults: a comprehensive update

INTRODUCTION

Opioid use disorder (OUD) is characterized by compulsive opioid seeking and taking, intense drug craving, and intake of opioids despite negative consequences. The prevalence of OUDs has now reached an all-time high, in parallel with peak rates of fatal opioid-related overdoses, where 15 million individuals worldwide meet the criteria for OUD. Further, in 2020, 120,000 opioid-related deaths were reported worldwide with over 75,000 of those deaths occurring within the United States.

AREAS COVERED

In this review, we highlight pharmacotherapies utilized in patients with OUDs, including opioid replacement therapies, and opioid antagonists utilized for opioid overdoses and deterrent of opioid use. We also highlight newer treatments, such as those targeting the neuroimmune system, which are potential new directions for research given the recently established role of opioids in activating neuroinflammatory pathways, as well as over the counter remedies, including kratom, that may mitigate withdrawal.

EXPERT OPINION

To effectively treat OUDs, a deeper understanding of the current therapeutics being utilized, their additive effects, and the added involvement of the neuroimmune system are essential. Additionally, a complete understanding of opioid-induced neuronal alterations and therapeutics that target these abnormalities - including the neuroimmune system - is required to develop effective treatments for OUDs.

Hepatotoxicity due to herbal dietary supplements: Past, present and the future

Dietary supplements (DS) constitute a widely used group of products comprising vitamin, mineral, and botanical extract formulations. DS of botanical or herbal origins (HDS) comprise nearly 30% of all DS and are presented on the market either as single plant extracts or multi-extract-containing products. Despite generally safe toxicological profiles of most products currently present on the market, rising cases of liver injury caused by HDS - mostly by multi-ingredient and adulterated products - are of particular concern. Here we discuss the most prominent historical cases of HDS-induced hepatotoxicty - from Ephedra to Hydroxycut and OxyELITE Pro-NF, as well as products with suspected hepatotoxicity that are either currently on or are entering the market. We further provide discussion on overcoming the existing challenges with HDS-linked hepatotoxicity by introduction of advanced in silico, in vitro, in vivo, and microphysiological system approaches to address the matter of safety of those products before they reach the market.

Kratom exposures managed by the British Columbia poison centre, 2012-2019: a descriptive analysis

BACKGROUND

Kratom, a plant indigenous to Southeast Asia, which has been used both recreationally and in the treatment of pain and opioid dependence, has received little scrutiny in the United States and almost none in Canada. We analyzed calls to the British Columbia poison centre to describe caller-declared exposures to kratom and the acute health effects of these exposures.

METHODS

For this descriptive analysis, we accessed electronic records, including transcriptions and extracted variables, of calls specifying kratom exposure managed by the BC Drug and Poison Information Centre (DPIC) from 2012 to 2019. We describe changes in case numbers, reasons for exposure, concurrent drug exposures and clinical outcomes over the study period.

RESULTS

We identified 32 cases during the study period. In 23 cases (72%), the DPIC was consulted by a health care worker. Case numbers increased from 0 in 2012 to 9 in 2019. Numbers were highest for males in their 20s (n = 17, 53%). A total of 27 cases (84%) involved ingestion, with online distributors and local stores named as sources of procurement. A concurrent drug exposure was identified in 13 (41%) cases. There were no deaths; in 1 case, the exposed individual was intubated to manage agitation following kratom withdrawal.

INTERPRETATION

We observed a steady increase in kratom-related poison centre calls from 2012 to 2019, especially in young adult males. Rising call numbers may reflect increasing availability of kratom and may be a consequence of BC's opioid crisis, with kratom used by some to lessen symptoms of opioid withdrawal.

Kratom (Mitragyna speciosa)-Induced Hepatitis

Kratom is a plant with opioid-like properties known to produce stimulant and analgesic effects. Although there are numerous studies on the psychoactive components of kratom, less is known about the toxicity. Specifically, few reports describe kratom-induced hepatotoxicity and demonstrate histological features. We provide a case report detailing the clinicopathologic findings of drug-induced liver injury caused by kratom. The laboratory workup included significant elevation of total bilirubin and alkaline phosphatase. Liver biopsy demonstrated a prominent canalicular cholestatic pattern, mixed portal inflammation, and newly described perivenular necrosis. This report provides additional information on kratom toxicity because its use continues to rise.

Understanding Kratom Use: A Guide for Healthcare Providers

Kratom (Mitragyna speciosa Korth., Rubiaceae) is a plant native to Southeast Asia, where it has been used for centuries as a mild stimulant and as medicine for various ailments. More recently, as kratom has gained popularity in the West, United States federal agencies have raised concerns over its safety leading to criminalization in some states and cities. Some of these safety concerns have echoed across media and broad-based health websites and, in the absence of clinical trials to test kratom’s efficacy and safety, considerable confusion has arisen among healthcare providers. There is, however, a growing literature of peer-reviewed science that can inform healthcare providers so that they are better equipped to discuss kratom use with consumers and people considering kratom use within the context of their overall health and safety, while recognizing that neither kratom nor any of its constituent substances or metabolites have been approved as safe and effective for any disease. An especially important gap in safety-related science is the use of kratom in combination with physiologically active substances and medicines. With these caveats in mind we provide a comprehensive overview of the available science on kratom that has the potential to i clarity for healthcare providers and patients. We conclude by making recommendations for best practices in working with people who use kratom.

Acute liver injury following short-term use of the herbal supplement kratom

ABSTRACT

Kratom, a tropical plant and dietary supplement with dose-dependent effects, has physiologic effects similar to opioids as well as stimulant effects. Kratom, like all dietary supplements, is not regulated in the United States and its effects have raised potential and safety concerns. This article describes a patient who presented to the ED with jaundice and acute liver injury, which after a thorough exclusion of alternative causes was attributed to kratom use.

Mitragyna Species as Pharmacological Agents: From Abuse to Promising Pharmaceutical Products

Mitragyna is a genus belonging to the Rubiaceae family and is a plant endemic to Asia and Africa. Traditionally, the plants of this genus were used by local people to treat some diseases from generation to generation. Mitragyna speciosa (Korth.) Havil. is a controversial plant from this genus, known under the trading name “kratom”, and contains more than 40 different types of alkaloids. Mitragynine and 7-hydroxymitragynine have agonist morphine-like effects on opioid receptors. Globally, Mitragyna plants have high economic value. However, regulations regarding the circulation and use of these commodities vary in several countries around the world. This review article aims to comprehensively examine Mitragyna plants (mainly M. speciosa) as potential pharmacological agents by looking at various aspects of the plants. A literature search was performed and information collected using electronic databases including Scopus, ScienceDirect, PubMed, directory open access journal (DOAJ), and Google Scholar in early 2020 to mid-2021. This narrative review highlights some aspects of this genus, including historical background and botanical origins, habitat, cultivation, its use in traditional medicine, phytochemistry, pharmacology and toxicity, abuse and addiction, legal issues, and the potential of Mitragyna species as pharmaceutical products.

The effect of mitragynine on extracellular activity of brain dopamine and its metabolites

Kratom, derived from the plant Mitragyna speciosa (M. speciosa) Korth is a traditional psychoactive preparation widely used in Southeast Asia and increasingly in the rest of the world. Use and abuse of Kratom preparations can be attributed to mitragynine (MIT), the main psychoactive compound isolated from its leaves. While MIT may have beneficial effects as a recreational drug, for pain management, and for opiate withdrawal, it may have an addiction potential at higher doses. However, its action in the reward system of the brain is currently unknown. This study investigated how mitragynine (10 mg/kg, i.p.) affects extracellular activity of dopamine (DA) and its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the prefrontal cortex (PFC), nucleus accumbens (NAc) and caudate putamen (CPu) of the brain, compared to morphine (MOR; 10 mg/kg, i.p.) and methamphetamine (METH; 10 mg/kg, i.p.). Using in-vivo microdialysis in freely moving rats, we found a significant increase of extracellular DA after MOR and METH, but not after MIT in all three brain regions. MIT led to a significant increase of DOPAC and/or HVA in these brain regions while MOR and METH had only moderate effects. These findings suggest a strong and prolonged effect of MIT on DA synthesis/metabolism, but not on extracellular DA activity, which may limit the addiction risk of MIT, in contrast to MOR and METH.

Mitragynine (Kratom)-Induced Cognitive Impairments in Mice Resemble Δ9-THC and Morphine Effects: Reversal by Cannabinoid CB1 Receptor Antagonism

Kratom is a widely abused plant-based drug preparation with a global interest in recent years, well beyond its native grounds in Southeast Asia. Mitragynine, its major psychoactive constituent is known to exhibit opioid-like behavioral effects with resultant neuroplasticity in the brain reward system. Its chronic administration is associated with cognitive impairments in animal studies. However, the underlying molecular mechanism for such a deficit remains elusive. In this study, the involvement of cannabinoid type-1 (CB₁) receptors in cognitive deficits after chronic mitragynine exposures was investigated for 28 days (with incremental dose sensitization from 1 to 25 mg/kg) in adult male Swiss albino mice using the IntelliCage^® system. Chronic high-dose mitragynine exposure (5–25 mg/kg, intraperitoneal [i.p.]), but not low-dose exposure (1–4 mg/kg, i.p.), induced hyperlocomotion, potentiated the preference for sucrose reward, increased resistance to punishment, and impaired place learning and its reversal. Comparable deficits were also observed after chronic treatments with Δ-9-tetrahydrocannabinol (THC, 2 mg/kg, i.p.) or morphine (5 mg/kg, subcutaneous). Mitragynine-, morphine-, and THC-induced learning and memory deficits were reversed by co-treatment with the CB₁ receptor antagonist, NIDA-41020 (10 mg/kg, i.p.). A significant upregulation of CB₁ receptor expression was found in the hippocampal CA1 region and ventral tegmental area after chronic high-dose mitragynine and morphine, whereas a downregulation was observed after chronic THC. In conclusion, the present study suggests a plausible role of the CB₁ receptor in mediating the dose-dependent cognitive deficits after chronic high-dose mitragynine exposure. This also highlights the potential of CB₁ receptor antagonism in ameliorating the cognitive deficits associated with long-term kratom/mitragynine consumption in humans.

Herb-induced liver injury: Systematic review and meta-analysis

BACKGROUND

The use of herbal supplements and alternative medicines has been increasing in the last decades. Despite popular belief that the consumption of natural products is harmless, herbs might cause injury to various organs, particularly to the liver, which is responsible for their metabolism in the form of herb-induced liver injury (HILI).

AIM

To identify herbal products associated with HILI and describe the type of lesion associated with each product.

METHODS

Studies were retrieved using Medical Subject Headings Descriptors combined with Boolean operators. Searches were run on the electronic databases Scopus, Web of Science, MEDLINE, BIREME, LILACS, Cochrane Library for Systematic Reviews, SciELO, Embase, and Opengray.eu. Languages were restricted to English, Spanish, and Portuguese. There was no date of publication restrictions. The reference lists of the studies retrieved were searched manually. To access causality, the Maria and Victorino System of Causality Assessment in Drug Induced Liver Injury was used. Simple descriptive analysis were used to summarize the results.

RESULTS

The search strategy retrieved 5918 references. In the final analysis, 446 references were included, with a total of 936 cases reported. We found 79 types of herbs or herbal compounds related to HILI. He-Shou-Wu, Green tea extract, Herbalife, kava kava, Greater celandine, multiple herbs, germander, hydroxycut, skullcap, kratom, Gynura segetum, garcinia cambogia, ma huang, chaparral, senna, and aloe vera were the most common supplements with HILI reported. Most of these patients had complete clinical recovery (82.8%). However, liver transplantation was necessary for 6.6% of these cases. Also, chronic liver disease and death were observed in 1.5% and 10.4% of the cases, respectively.

CONCLUSION

HILI is normally associated with a good prognosis, once the implied product is withdrawn. Nevertheless, it is paramount to raise awareness in the medical and non-medical community of the risks of the indiscriminate use of herbal products.

New Designer Drugs

In recent years, there has been an emergence of numerous novel drugs. Such toxicity may occur in both adolescents and adults. This article discusses the opioid epidemic and several emerging opioids, including buprenorphine, loperamide, fentanyl, fentanyl derivatives, and others. Kratom, a plant occasionally used for opiate detoxification, along with the sedatives etizolam and phenibut, will be discussed. Lastly, this article discusses the phenethylamines and marijuana.

Kratom-induced transaminitis with subsequent precipitated opioid withdrawal following naltrexone

Kratom is an herbal supplement that has gained popularity for recreational use within the United States. Kratom exerts opioid-like effects and, although not US FDA approved, is commonly used for self-treatment of pain, withdrawal management from opioids, and euphoria. Drug-related hepatic injury has been associated with kratom use. All of this raises concern for patient safety and monitoring. The potential for additive liver toxicity must be considered when kratom is used concurrently with hepatotoxic, over-the-counter, herbal, and prescription medications. This case report describes a case of kratom-induced liver inflammation complicated by opioid withdrawal that was precipitated by initiation of IM naltrexone. To our knowledge, there are no published case reports related to opioid withdrawal following naltrexone administration in patients using kratom (without other opioids). The purpose of this case report is to demonstrate potential complications that may arise with kratom use and considerations that should be taken prior to initiation of naltrexone in kratom users.

The Right to Use Kratom from the Psychiatric and Islamic Perspectives

This paper aimed to summarize kratom's psychological effects on users and the Islamic views on kratom use. A literature survey of published kratom studies, teachings based on the holy Qur'an, the Sunnah, and views of several Islamic scholars based on qualitative methodology through text analysis was conducted. The results demonstrated that despite its beneficial therapeutic effects, the harm induced by kratom outweighs its benefits. We concluded that kratom use for medicinal purposes is only warranted if useful constituent mitragynine can be extracted and used on its own, and if more rigorous human studies demonstrated good safety profile and efficacy of mitragynine for therapeutic purposes.

Intracerebral hemorrhage after kratom ingestion

ABSTRACT

Mitragyna speciosa, a tropical tree also known as kratom, is an emerging substance of abuse with dose-dependent stimulant and opioid-like effects. Kratom may be purchased legally in the United States and is marketed online as a safe alternative to opioids and a cheap alternative to opioid replacement therapy. However, adverse reactions to ingestion are largely unknown and may pose a significant public health risk. This article describes a man with an intracerebral hemorrhage possibly secondary to kratom ingestion.

Case Report: Treatment of Kratom Use Disorder With a Classical Tricyclic Antidepressant

Kratom or Mitragyna speciosa (Korth.) is an evergreen tree of the coffee family native to South-East Asia and Australasia. It is used by locals recreationally to induce stimulant and sedative effects and medically to soothe pain and opiate withdrawal. Its leaves are smoked, chewed, or infused, or ground to yield powders or extracts for use as liquids. It contains more than 40 alkaloids; among these, mitragynine and 7-hydroxymitragynine are endowed with variable mu, delta, and kappa opioid stimulating properties (with 7-hydroxymitragynine having a more balanced affinity), rhynchophylline, which is a non-competitive NMDA glutamate receptor antagonist, but is present in negligible quantities, and raubasine, which inhibits α₁-adrenceptors preferentially over α₂-adrenceptors, while the latter are bound by 7-hydroxymitragynine, while mitragynine counters 5-HT_2A receptors. This complexity of neurochemical mechanisms may account for kratom's sedative-analgesic and stimulant effects. It is commonly held that kratom at low doses is stimulant and at higher doses sedative, but no cut-off has been possible to define. Long-term use of kratom may produce physical and psychological effects that are very similar to its withdrawal syndrome, that is, anxiety, irritability, mood, eating, and sleep disorders, other than physical symptoms resembling opiate withdrawal. Kratom's regulatory status varies across countries; in Italy, both mitragynine and the entire tree and its parts are included among regulated substances. We describe the case of a patient who developed anxiety and dysphoric mood and insomnia while using kratom, with these symptoms persisting after withdrawal. He did not respond to a variety of antidepressant combinations and tramadol for various months, and responded after 1 month of clomipramine. Well-being persisted after discontinuing tramadol.

A comparative analysis of kratom exposure cases in Thailand and the United States from 2010-2017

Background: Interest in the Southeast Asian natural remedy kratom has increased in Western countries recently, along with increasing concern over its potential toxic effects.Objective: To describe and compare demographics, common co-exposure substances, clinical effects, treatments, and medical outcomes of kratom "abuse" exposures in the United States (US) and Thailand.Methods: This is a retrospective analysis of kratom "abuse" exposures, defined as use when attempting to gain a psychotropic effect, reported to the National Poison Data System (NPDS) in the US and the Ramathibodi Poison Center (RPC) in Thailand from 2010 to 2017. Multivariate analysis identified risk factors for severe medical outcomes, defined as both ICU admissions and death.Results: Nine-hundred-twenty-eight cases were included (760 from NPDS and 168 from RPC). A greater proportion of cases involved co-exposures in Thailand (64.8% versus 37.4%; odds ratio [OR] = 3.10, 95% confidence interval [CI] = 2.15-4.47, p < .01). Both countries had a similar prevalence of opioid and benzodiazepine co-ingestions, but the US had more co-ingestions with other sedatives (4.6% versus 0%, OR = 0, 95% CI = 0-0.47, p < .01). Common clinical effects included tachycardia (30.4%), agitation/irritability (26.2%), and drowsiness/lethargy (21.1%). Six deaths occurred, including one single-substance exposure in the US, three multiple-substance exposures in the US, and two multiple-substance exposures in Thailand. Severe medical outcomes were reported more frequently in the US (OR = 18.82, 95% CI = 5.85-60.56, p < .01).Conclusions: Despite lower frequencies of co-ingestants overall, US kratom abuse exposures yielded greater clinical severity. This disparity may be attributable to differences in the products labeled "kratom," greater sedative co-exposures in the US, and/or differences in population genetics or use patterns.

Kratom induced severe cholestatic liver injury histologically mimicking primary biliary cholangitis: A case report

BACKGROUND

Kratom is a psychoactive substance that is isolated from the plant Mitragyna speciosa. The leaves can be chewed fresh or dried, smoked, or infused similar to herbal teas. The plant leaves have been used by natives of Southeast Asia for centuries. The substance has been used for its stimulant activity at low doses, and as an opium substitute at higher doses due to a morphine like effect.

CASE SUMMARY

A 37-year-old female with a history of depression and obesity (body mass index: 32) presented to emergency room with a week-long history of nausea, decreased appetite, fatigue, and two days of jaundice. On admission bilirubin was markedly elevated. Her condition was thought to be due to consumption of Kratom 2 wk before onset of symptoms. Liver biopsy showed changes mimicking primary biliary cholangitis. Patient’s symptoms and jaundice improved quickly.

CONCLUSION

The use of Kratom has been on the rise in recent years across the United States and Europe. Several case reports have associated adverse health impact of Kratom-containing products including death due to its ability to alter levels of consciousness. Only a few case reports have highlighted the hepatotoxic effects of Kratom. Even fewer reports exist describing the detailed histopathological changes.

Kratom (Mitragyna Speciosa) Liver Injury: A Comprehensive Review

Kratom (Mitragyna speciosa) leaves contain the mu opioid partial agonists mitragynine and 7-hydroxymitragynine. The US Drug Enforcement Agency considers it a 'drug of concern', and the US FDA is reviewing kratom, but there is a paucity of information regarding health effects. Liver injury is often cited as a potential health consequence, however the same few case reports are repeatedly referenced, without a broader context. Furthermore, reports have largely lacked standardized causality assessment methods. The objective is to evaluate causality in kratom liver injury, through a comprehensive scoping review of human cases, and by reviewing epidemiologic, animal, and mechanistic reports that relate to kratom liver injury. Hepatotoxicity causality was systematically examined using the Roussel Uclaf Causality Assessment Method (RUCAM) for case reports. Biopsy findings, potential pathophysiologic mechanisms, and management options are discussed. This review identified 26 case reports and abstracts, in addition to 7 cases reported from the Drug-Induced Liver Injury Network, 25 in FDA databases, and 27 in internet user forums. Latency periods to symptom onset had a median of 20.6 days and mean of 21 days (range 2-49). Common presenting signs and symptoms were abdominal discomfort, jaundice, pruritis, and dark urine. Histologic findings were predominantly cholestatic, although, biochemically, the condition was heterogenous or mixed; the median R ratio was 3.4 and the mean was 4.6 (range 0.24-10.4). Kratom likely causes liver injury based on the totality of low-quality human evidence, and, in the context of epidemiologic, animal, and mechanistic studies. It remains unclear which subgroups of users are at heightened risk.

Kratom-Induced Cholestatic Liver Injury and Its Conservative Management

Drug-induced liver injury (DILI) is a common cause of hepatotoxicity associated with prescription-based and over-the-counter exposure to medications and herbal supplements. Use of unapproved and inadequately tested herbal supplements can cause DILI. Therefore, thorough history-taking on exposure to herbal supplements must be an integral part of clinical evaluation of DILI. Kratom is an herbal supplement or remedy that has been known for its analgesic effects and has also been used for self-treatment of opiate withdrawals. A 52-year-old man was seen for evaluation of yellow discoloration of the eyes and skin. He reported taking kratom for right shoulder strain for at least a couple of months. On workup, his total bilirubin was noted to be 23.2 mg/dL, which peaked at 28.9 mg/dL. He was noted to have mild elevation of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase. Extensive laboratory tests were ordered and known causes of chronic liver disease ruled out. Magnetic resonance imaging of the abdomen was unremarkable without stigmata of portal hypertension or signs of chronic liver disease. He demonstrated no evidence of coagulopathy or hepatic encephalopathy during his illness. He underwent liver biopsy, which demonstrated histologic evidence of acute cholestatic hepatitis highly suspicious of DILI. He was advised to avoid kratom or other herbal supplements in future and prescribed ursodeoxycholic acid with significant improvement in his liver chemistries. Kratom is associated with significant liver enzymes derangements leading to DILI. Kratom is not approved for use in the United States and should be avoided.

Drug-Induced Liver Injury Caused by Kratom Use as an Alternative Pain Treatment Amid an Ongoing Opioid Epidemic

Kratom (Mitragyna speciosa) is a prevalent medicinal plant used mainly for the stimulant and analgesic properties provided through multiple alkaloid compounds. Over the past decade, use of kratom has increased despite the limited knowledge of toxicities and adverse side effects. With the current opioid epidemic, both patients and providers are seeking alternative methods to treat both addiction and pain control, and kratom as an alternative means of treatment has increasingly entered the mainstream. In this article, we present the clinical course of a 47-year-old male who developed fatigue, pruritus, and abnormal liver tests (with a mixed hepatocellular/cholestatic pattern) approximately 21 days after beginning kratom. After extensive evaluation including a negligible alcohol history, negative hepatitis serologies, and inconclusive imaging, the patient was diagnosed with drug-induced liver injury (DILI) caused by kratom. Nine months after his liver tests returned to normal, he took kratom again, and after a latency of 2 days, he developed fatigue, pruritus, and loss of appetite along with abnormal liver tests (with the same biochemical profile as previously), consistent with a positive rechallenge. We believe, through the use of the Roussel-Uclaf Causality Assessment Method and expert opinion, that this is a highly likely or definite example of kratom-induced DILI. With the gaining popularity of this drug, it appears that DILI may be an important complication of kratom for providers to recognize.

A Complex Case of Kratom Dependence, Depression, and Chronic Pain in Opioid Use Disorder: Effects of Buprenorphine in Clinical Management

Mitragyna speciosa (Kratom) is a psychotropic tropical tree that is indigenous to Southeast Asia, Africa and New Guinea. Kratom has gained popularity in the United States in more recent years as an opioid agonist. Although Kratom is considered an opioid agonist with abuse potential, its use is not federally regulated. We report on a 47 year-old male presenting to our clinic for treatment of an opioid use disorder. This began with the use of prescription opioids from a doctor, and when this was no longer available this patient started using Kratom. He had used Kratom for one year to treat opioid withdrawal symptoms and chronic pain, resulting in worsening depression, anxiety and pain. He experienced tolerance and withdrawal symptoms related to Kratom. He was initiated on buprenorphine-naloxone at home with improved pain management. Four months after initiation, the patient's depression and anxiety symptoms resolved, and he was able to discontinue his antidepressant and anxiolytic medications. Kratom dependence and withdrawal appear similar to that of opioids, and may also lead to worsening depression and anxiety. Buprenorphine-naloxone may be a viable option to consider for treating opioid use disorder complicated by Kratom use, chronic pain, and depression.

Lipid profile of regular kratom (Mitragyna speciosa Korth.) users in the community setting

Background and aim

Kratom, or Mitragyna speciosa Korth., is a tropical plant that has been reported to exhibit opioid-like effects. Although opioids have been demonstrated to alter the lipid profile of regular users, data on the lipid-altering effects of kratom are scarce. This study aimed to compare the fasting lipid profile of regular kratom users to that of healthy subjects who do not use kratom. It also determined the association between various characteristics of kratom users and the serum triglycerides, total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels of regular kratom users.

Methods

A total of 200 participants (n = 100 kratom users and n = 100 healthy subjects who do not use kratom) were recruited for this analytical cross-sectional study. Data on sociodemographic status, kratom use characteristics, cigarette smoking, physical activity, body mass index (BMI), fasting serum lipid profile, and liver function were collected from all participants.

Results

The liver parameters of the study participants were within normal range. The serum total cholesterol and LDL of kratom users were significantly lower than those of healthy subjects who do not use kratom. There were no significant differences in the serum triglyceride and HDL levels. However, higher average daily frequency of kratom use and increasing age were associated with increased serum total cholesterol among kratom users. Other kratom use characteristics such as age of first kratom intake, duration of kratom use, and quantity of daily kratom intake were not associated with increased serum triglyceride, total cholesterol, LDL, and HDL levels.

Conclusions

Our findings suggest regular kratom consumption was not linked to elevated serum lipids, except when there is a higher frequency of daily kratom intake. However, the study was limited by the small sample size, and hence a more comprehensive study with larger sample size is warranted to confirm the findings.

Kratom-Pharmacology, Clinical Implications, and Outlook: A Comprehensive Review

Kratom, or Mitragyna, is a tropical plant indigenous to Southeast Asia, with unique pharmacological properties. It is commonly consumed by preparing the leaves into decoction or tea, or by grinding them into a powder. Recent evidence has revealed that kratom has physiological effects similar to opioids, including pain relief and euphoria, as well as stimulant properties, which together raise potential concern for dependence and addiction. Moreover, growing evidence suggests that the prevalence of kratom use is increasing in many parts of the world, raising important considerations for healthcare providers. This manuscript will discuss the most current epidemiology, pharmacology, toxicity, and management related to kratom, while seeking to provide a contemporary perspective on the issue and its role in the greater context of the opioid epidemic.

Mitragynine, an euphoric compound inhibits hERG1a/1b channel current and upregulates the complexation of hERG1a-Hsp90 in HEK293-hERG1a/1b cells

Mitragyna speciosa Korth (M. speciosa) has been widely used as a recreational product, however, there are growing concerns on the abuse potentials and toxicity of the plant. Several poisoning and fatal cases involving kratom and mitragynine have been reported but the underlying causes remain unclear. The human ether-a-go-go-related gene 1 (hERG1) encodes the pore-forming subunit underlying cardiac rapidly delayed rectifier potassium current (I_Kr). Pharmacological blockade of the I_Kr can cause acquired long QT syndrome, leading to lethal cardiac arrhythmias. This study aims to elucidate the mechanisms of mitragynine-induced inhibition on hERG1a/1b current. Electrophysiology experiments were carried out using Port-a-Patch system. Quantitative RT-PCR, Western blot analysis, immunofluorescence and co-immunoprecipitation methods were used to determine the effects of mitragynine on hERG1a/1b expression and hERG1-cytosolic chaperones interaction. Mitragynine was found to inhibit the I_Kr current with an IC₅₀ value of 332.70 nM. It causes a significant reduction of the fully-glycosylated (fg) hERG1a protein expression but upregulates both core-glycosylated (cg) expression and hERG1a-Hsp90 complexes, suggesting possible impaired hERG1a trafficking. In conclusion, mitragynine inhibits hERG1a/1b current through direct channel blockade at lower concentration, but at higher concentration, it upregulates the complexation of hERG1a-Hsp90 which may be inhibitory towards channel trafficking.

Kratom from Head to Toe—Case Reviews of Adverse Events and Toxicities

Purpose of Review

This review describes case reports for patients with kratom-associated adverse events in order to assist clinicians with patient management. A stepwise approach is proposed for assessing active kratom users as well as considerations for the management of toxicities or withdrawal.

Recent Findings

Multiple in vitro and in vivo studies illustrate the pharmacologic and toxicologic effects of kratom extract. No randomized controlled trials in humans exist that assess the safety and efficacy of the substance. Cross-sectional surveys from active users and reports from poison control centers have shown acute and chronic physiological and psychological adverse events.

Summary

Reports of adverse effects associated with kratom use have demonstrated hypothyroidism, hypogonadism, hepatitis, acute respiratory distress syndrome, posterior reversible encephalopathy syndrome, seizure, and coma. Overdose toxidrome leads to respiratory failure, cardiac arrest, and fatalities. Adult and neonatal withdrawal symptoms have also occurred. Clinicians should be aware of the risks and benefits of kratom use.

Characteristics of deaths associated with kratom use

BACKGROUND

Kratom (Mitragyna speciosa Korth) use has increased in Western countries, with a rising number of associated deaths. There is growing debate about the involvement of kratom in these events.

AIMS

This study details the characteristics of such fatalities and provides a 'state-of-the-art' review.

METHODS

UK cases were identified from mortality registers by searching with the terms 'kratom', 'mitragynine', etc. Databases and online media were searched using these terms and 'death', 'fatal*', 'overdose', 'poisoning', etc. to identify additional cases; details were obtained from relevant officials. Case characteristics were extracted into an Excel spreadsheet, and analysed employing descriptive statistics and thematic analysis.

RESULTS

Typical case characteristics (n = 156): male (80%), mean age 32.3 years, White (100%), drug abuse history (95%); reasons for use included self-medication, recreation, relaxation, bodybuilding, and avoiding positive drug tests. Mitragynine alone was identified/implicated in 23% of cases. Poly substance use was common (87%), typically controlled/recreational drugs, therapeutic drugs, and alcohol. Death cause(s) included toxic effects of kratom ± other substances; underlying health issues.

CONCLUSIONS

These findings add substantially to the knowledge base on kratom-associated deaths; these need systematic, accurate recording. Kratom's safety profile remains only partially understood; toxic and fatal levels require quantification.

Kratom-Induced Cholestatic Liver Injury Mimicking Anti-Mitochondrial Antibody-Negative Primary Biliary Cholangitis: A Case Report and Review of Literature

Kratom is an herbal supplement used to relieve chronic pain or opioid withdrawal symptoms. Recent news articles covering adverse effects associated with kratom use have brought attention to its organ toxicities. Reports of kratom-induced hepatic toxicity are limited and only three case reports of kratom-induced liver injury with histopathologic examination of the liver biopsies are available. A 40-year-old female presented with symptoms of mixed cholestatic and hepatocellular liver injury without clear etiology. The laboratory and imaging workup suggested possibilities of autoimmune hepatitis, autoimmune hepatitis-primary biliary cholangitis (PBC) overlap syndrome, or drug-induced liver injury. Autoantibodies including anti-mitochondrial antibody (AMA) were negative. Liver biopsy showed granulomatous hepatitis with prominent duct injury, suggestive of AMA-negative PBC. She subsequently was referred to a hepatologist and a history of recent kratom use was finally revealed. Kratom was discontinued and the symptoms improved. Kratom-induced hepatic toxicity may manifest with variable biochemical and clinical abnormalities. Histologically, it may mimic AMA-negative PBC. Our case highlights the importance of thorough history taking, interdisciplinary approach and communication for optimal patient care.

Detection and Identification of Kratom (Mitragyna speciosa) and Marijuana (Cannabis sativa) by a Real-Time Polymerase Chain Reaction High-Resolution Melt Duplex Assay. J Forensic Sci 2019;65:52-60. [PMID: 31433500 DOI: 10.1111/1556-4029.14167]

Mitragyna speciosa (MS), a plant commonly known as kratom, is a widely used "legal high" opiate alternative for pain relief. DNA extracted from MS and 26 additional plant species was amplified by PCR using primers targeting the strictosidine beta-D-glucosidase (SGD) and secologanin synthase 2 (SLS2) genes and detected by high-resolution melt curves using three intercalating dyes. Amplicon sizes were confirmed using agarose gel electrophoresis. The observed melt temperatures for SGD and SLS2 were 77.08 ± 0.38°C and 77.61 ± 0.46°C, respectively, using SYBR^® Green I; 80.18 ± 0.27°C and 80.59 ± 0.08°C, respectively, using Radiant^™ Green; and 82.19 ± 0.04°C and 82.62 ± 0.13°C, respectively, using the LCGreen^® PLUS dye. The SLS2 primers demonstrated higher specificity and identified MS DNA at 0.05 ng/μL. In a duplex reaction, SLS2 and tetrahydrocannabinoic acid synthase gene primers detected and differentiated MS and Cannabis sativa (CS) by melt peaks at 82.63 ± 0.35°C and 85.58 ± 0.23°C, respectively, using LCGreen^® PLUS.

The Trouble With Kratom: Analytical and Interpretative Issues Involving Mitragynine

Mitragynine is the primary active alkaloid in the leaves of the tropical tree Mitragyna speciosa, and goes by the popular names “Kratom”, biak-biak and maeng da. Mitragynine is increasingly seen in forensic toxicology casework including driving under the influence of drugs and medicolegal death investigation cases. The toxicity of mitragynine continues to be debated in the scientific community as advocates highlight its long history of use in Southeast Asia and testimonials to its benefits by present-day users, while opponents point to an increasing number of adverse events tied to mitragynine use in Western societies. Quantitative reports of mitragynine in biological specimens from forensic investigations in the literature are sparse and may be influenced by poor analyte stability and inadequate resolution of mitragynine from its diastereomers, which could lead to falsely elevated concentrations and subsequently render those reported concentrations inappropriate for comparison to a reference range. Over the course of 27 months, 1,001 blood specimens submitted to our laboratory tested positive for mitragynine using a sensitive and specific quantitative LC-MS/MS method; concentrations ranged from 5.6–29,000 ng/mL, with mean and median concentrations of 410 ± 1,124 and 130 ng/mL, respectively. Mitragynine presents an analytical challenge that requires a method that appropriately separates and identifies mitragynine itself from its isomers and other related natural products. We describe a validated analytical method and present a short series of case reports that provide examples of apparent adverse events, and the associated range of mitragynine concentrations. This type of analytical specificity is required to appropriately interpret mitragynine concentrations detected in biological specimens from forensic casework and assess its potential toxicity.

Cardiac arrest in a young healthy male patient secondary to kratom ingestion: is this 'legal high' substance more dangerous than initially thought ?

Kratom is a psychoactive herb that has stimulant properties at low doses and has opioid-like properties at higher doses. It has been used for centuries in southeast Asia as a stimulant but has gained increasing popularity as a substitute for opioids in western countries as it is easily available. As most cases of kratom use involve other drugs too, the Food and Drug Administration (FDA) has stopped short of restricting kratom due to difficulty in assessing the adverse effects of kratom alone. We present the case of a young healthy 35-year-old man who suffered a cardiac arrest due to kratom use with no other coingestants. He was subsequently intubated and found to have systolic dysfunction and small brain infarcts. Fortunately, he made a successful recovery and was discharged after a stay at thebehavioural health centre. Our case highlights the potential adverse effects of kratom and the need to regulate its use.

Current perspectives on the impact of Kratom use

The leaves from the tree Mitragyna speciosa, commonly known as Kratom, in the coffee plant family (Rubiaceae) are commonly used in their native habitat of Southeast Asia as a stimulant to sustain energy during hard day labor and as an opioid-like analgesic and sedative. Traditional and modern uses overlap based on the effects of the leaf extract which has also gained popularity in the United States and Europe in the last two decades. Kratom has and is being used for the mitigation of opioid withdrawal symptoms and as a harm reduction agent with a minority of users subsequently developing a dependence on the extract. The respective demographic use patterns of Kratom differ between Southeast Asia and the Western world. While pure Kratom is primarily used by day laborers and misused in conjunction with cough medicine by youth in Southeast Asia, a majority of users in the United States is middle-aged, has at least middle income, private health insurance, and completed some college. Deaths attributed to the use of Kratom have been reported in Europe and the United States but not in Southeast Asia. Although Kratom was detected as the alkaloid mitragynine in the blood of the decedents, causality could not be established in almost all cases because of poly-drug exposures. It is notable that Kratom can cause herb–drug interactions, especially with other central nervous system -active substances. Given the mostly unregulated market for Kratom products in Western countries, consumers may be exposed to adulterated or contaminated products, especially if purchased through websites or the darknet. A number of countries have scheduled Kratom because of its stimulant- and opioid-like effects and the established interaction of the alkaloid mitragynine with opioid receptors.

Self-reported prevalence and severity of opioid and kratom (Mitragyna speciosa korth.) side effects

ETHNOPHARMACOLOGICAL RELEVANCE

Mitragyna speciosa (Korth.) is a traditional medicinal plant widely used in Southeast Asia for its opioid-like effects. Although kratom produces analgesia through binding of mitragynine and other alkaloids at the mu-opioid receptor (MOR), the association of long-term kratom use with adverse opioid-like effects remains unknown.

AIM OF THE STUDY

To determine the self-reported prevalence and severity of opioid-related adverse effects after kratom initiation in a cohort of illicit opioid users.

MATERIALS AND METHODS

A total of 163 illicit opioid users with current kratom use history were recruited through convenience sampling from the northern states of Peninsular Malaysia. Face-to-face interviews were conducted using a semi-structured questionnaire.

RESULTS

Respondents were all males, majority Malays (94%, n = 154/163), with a mean age of 37.10 years (SD = 10.9). Most were single (65%, n = 106/163), had 11 years of education (52%, n = 85/163) and employed (88%, n = 144/163). Half reported using kratom for over >6 years (50%, n = 81/163), and 41% consumed >3 glasses of kratom daily (n = 67/163). Results from Chi-square analysis showed kratom initiation was associated with decreased prevalence of respiratory depression, constipation, physical pain, insomnia, depression, loss of appetite, craving, decreased sexual performance, weight loss and fatigue.

CONCLUSIONS

Our findings indicate that kratom initiation (approximately 214.29 mg of mitragynine) was associated with significant decreases in the prevalence and severity of opioid adverse effects.

Kratom policy: The challenge of balancing therapeutic potential with public safety

Kratom (Mitragyna speciosa) is a tree-like plant indigenous to Southeast Asia. Its leaves, and the teas brewed from them have long been used by people in that region to stave off fatigue and to manage pain and opioid withdrawal. Evidence suggests kratom is being increasingly used by people in the United States and Europe for the self-management of opioid withdrawal and treatment of pain. Recent studies have confirmed that kratom and its chemical constituents have potentially useful pharmacological actions. However, there have also been increasing numbers of reports of adverse effects resulting from use of kratom products. In August 2016, the US Drug Enforcement Administration announced plans to classify kratom and its mitragynine constituents as Schedule I Controlled Substances, a move that triggered a massive response from pro-kratom advocates. The debate regarding the risks, and benefits and safety of kratom continues to intensify. Kratom proponents tout kratom as a safer and less addictive alternative to opioids for the management of pain and opioid addiction. The anti-kratom faction argues that kratom, itself, is a dangerous and addictive drug that ought to be banned. Given the widespread use of kratom and the extensive media attention it is receiving, it is important for physicians, scientists and policy makers to be knowledgeable about the subject. The purpose of this commentary is to update readers about recent developments and controversies in this rapidly evolving area. All of the authors are engaged in various aspects of kratom research and it is our intention to provide a fair and balanced overview that can form the basis for informed decisions on kratom policy. Our conclusions from these analyses are: (a) User reports and results of preclinical studies in animals strongly suggest that kratom and its main constituent alkaloid, mitragynine may have useful activity in alleviating pain and managing symptoms of opioid withdrawal, even though well-controlled clinical trials have yet to be done. (b) Even though kratom lacks many of the toxicities of classic opioids, there are legitimate concerns about the safety and lack of quality control of purported "kratom" products that are being sold in the US. (c) The issues regarding the safety and efficacy of kratom and its mitragynine constituent can only be resolved by additional research. Classification of the Mitragyna alkaloids as Schedule I controlled substances would substantially impede this important research on kratom.