Death from Kratom toxicity and the possible role of intralipid

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 update on the clinical pharmacology of kratom: uses, abuse potential, and future considerations

INTRODUCTION

Kratom (Mitragyna speciosa) has generated substantial clinical and scientific interest as a complex natural product. Its predominant alkaloid mitragynine and several stereoisomers have been studied for activity in opioid, adrenergic, and serotonin receptors. While awaiting clinical trial results, the pre-clinical evidence suggests a range of potential therapeutic applications for kratom with careful consideration of potential adverse effects.

AREAS COVERED

The focus of this review is on the pharmacology, pharmacokinetics, and potential drug-drug interactions of kratom and its individual alkaloids. A discussion on the clinical pharmacology and toxicology of kratom is followed by a summary of user surveys and the evolving concepts of tolerance, dependence, and withdrawal associated with kratom use disorder.

EXPERT OPINION

With the increasing use of kratom in clinical practice, clinicians should be aware of the potential benefits and adverse effects associated with kratom. While many patients may benefit from kratom use with few or no reported adverse effects, escalating dose and increased use frequency raise the risk for toxic events in the setting of polysubstance use or development of a use disorder.

Cardiovascular health in kratom users; a narrative review

BACKGROUND

Kratom, also known as Mitragyna speciosa, is a plant that originates in Southeast Asia and possesses unique pharmacological characteristics. It is commonly consumed in the form of tea made by boiling the leaves or using the leaves to create the powder. According to its pain-relieving effects, the prevalence of kratom use around the world has increased, which has various implications for healthcare providers. Mitragynine is a well-known active compound in kratom.

OBJECTIVE

This review aims to provide a comprehensive perspective on the cardiovascular effects of mitragynine and its potential cardiotoxicity through the literature.

METHOD

Authors searched PubMed, Scopus, and Google Scholar databases using appropriate search strategies for each database. After the screening, all relevant studies were included.

RESULTS

Although kratom may have the potential for therapeutic benefits, it has been associated with multi-organ damage and cardiac toxicity in some cases. According to the available data, tachycardia and hypertension are the most common adverse effects. Other possible cardiovascular effects include atherosclerosis, ventricular arrhythmia, cardiomyopathy, dose-dependent prolonged QTc interval, myocarditis, cardiomegaly, and cardiopulmonary arrest.

CONCLUSION

While prior research has indicated the possible negative effects of mitragynine overdose on the cardiovascular system, there are no definitive conclusions, and additional investigations are needed.

Mitragyna speciosa (Kratom) poisoning: Findings from ten cases

Kratom is a mixture of compounds that are present in the leaves of the tropical tree Mitragyna speciosa. It is used as a psychoactive agent with both opiate and stimulant-like effects. In this case series we describe the signs, symptoms, and the management of kratom overdose in the prehospital setting and in intensive care. We retrospectively searched for cases in the Czech Republic. Over 36 months we found 10 cases of kratom poisoning, which healthcare records were analyzed and reported as per CARE guidelines. The dominant symptoms in our series were neurological and included quantitative (n = 9) or qualitative (n = 4) disorder of consciousness. Signs and symptoms of vegetative instability [hypertension (n = 3) and tachycardia (n = 3) vs. bradycardia/cardiac arrest (n = 2), mydriasis (n = 2) vs. miosis (n = 3)] were noticed. Prompt response to naloxone in two cases and lack of response in one patient were observed. All patients survived and the effect of intoxication wore off within two days. Kratom overdose toxidrome is variable and, in keeping with its receptor physiology, consists of signs and symptoms of opioid-like overdose, sympathetic overactivation and serotonin-like syndrome. Naloxone can help to avoid intubation in some cases.

Two Single Drug Fatal Intoxications By Mitragynine

Mitragyna speciosa, a species of plant that is native to Thailand, Malaysia and Southeast Asia, contains two major psychoactive alkaloids: mitragynine and 7-hydroxymitragynine. Pharmacologically, the alkaloids exhibit biphasic effects - at low dose, stimulant effects are realized, while high doses exhibit sedative effects. For years, the plant has been used recreationally and medicinally for these effects, but its use has been implicated in and associated with intoxications and deaths. In this case report we describe two cases whereby decedents presented with single substance fatal intoxications by mitragynine in the absence of other postmortem toxicological findings. The cases entail young male decedents in outdoor settings (e.g. driving a vehicle and bicycle). Postmortem blood concentrations were 2,325 ng/mL and 3,809 ng/mL. The medical examiner (ME) certified cause of death (COD) as acute mitragynine intoxication in both cases. The toxicology results presented become useful when considering mitragynine to be the offending agent in lethal single drug intoxications; further, the information included is pertinent to medical examiners, forensic pathologists, forensic toxicologists, and emergency department personnel in evaluating possible poisoning and lethality by mitragynine.

PCR combined with lateral flow immunochromatographic assay to differentiate the narcotic Mitragyna speciosa from related species and detect it in forensic evidence

Plants in the genus Mitragyna (Rubiaceae) are used in traditional medicine because of their broad therapeutic activity. Four Mitragyna species, M. speciosa (Roxb.) Korth. (MS), M. rotundifolia (Roxb.) Kuntze (MR), M. diversifolia (Wall. ex G. Don) Havil. (MD), and M. hirsuta Havil. (MH), occur in Thailand. M. speciosa, commonly known as 'Kratom' in Thai, is the only narcotic species for which buying, selling, importing or possessing has been prohibited by law in Thailand and some other countries. Mitragynine and 7-hydroxymitragynine, the major psychoactive compounds, are important in the treatment of opioid withdrawal. However, this species is used in traditional medicine to relieve pain and inflammation. Consequently, a rapid and easy technique for differentiating M. speciosa from closely related species is needed for routine forensic analysis. In this study, polymerase chain reaction coupled with lateral flow immunochromatographic assay (PCR-LFA) based on matK was developed for the detection of M. speciosa in forensic specimens. Duplex primers (MS-F-FAM, Ctrl-F-DIG and Ctrl-R-Biotin) were designed based on species-specific nucleotide indels observed exclusively in the matK sequences of M. speciosa. Positive results for M. speciosa are indicated by the clear presence of three black lines on the lateral flow cassette. Forensic samples were investigated, and the three black test lines indicating M. speciosa were observed for seven of eight specimens. PCR-LFA has been proven to be fast, easy and efficient for detecting the narcotic M. speciosa and could be developed as a rapid forensic diagnostic technique for other plants.

Characterization of urinary protein profile in regular kratom (Mitragyna speciosa korth.) users in Malaysia

Mitragyna speciosa (Korth.) also known as kratom or ketum has been traditionally used for its diverse medicinal value in Southeast Asia. Despite of its therapeutic value, kratom's safety profile remains deficiently elucidated. Our study aims to characterize the urinary protein profile of regular kratom users to determine its toxic effects on renal functioning. A total of 171 respondents (comprising of n = 88 regular kratom users, and n = 83 healthy controls) were recruited for this study. Urine specimens were collected and analyzed using SDS-PAGE, followed by LC/MS/MS analysis. Our results show albumin is the primary, and most abundant form of protein excreted in kratom user's urine specimens (n = 60/64), indicating that kratom users are predisposed to proteinuria. Kratom users had an elevated urinary protein (with an intensity of 66.7 kDa band), and protein: creatinine ratio (PCR) concentrations relative to healthy controls. However, kratom user's urinary creatinine concentration was found to be in the normal range as the healthy control group. While, kratom users who tested positive for illicit drug use had an elevated urinary albumin concentration. Our preliminary findings indicate that regular consumption of freshly brewed kratom solution over a protracted period (for an average of eleven years) seems to induce proteinuria, suggestive of an early stage of kidney injury. Hence, further studies are urgently needed to confirm our findings, and establish kratom's renal impairing effects.

The Adverse Cardiovascular Effects and Cardiotoxicity of Kratom (Mitragyna speciosa Korth.): A Comprehensive Review

Background: Kratom or Mitragyna speciosa (Korth.) has received overwhelming attention recently due to its alleged pain-relieving effects. Despite its potential therapeutic value, kratom use has been linked to many occurrences of multiorgan toxicity and cardiotoxicity. Accordingly, the current narrative review aimed to provide a detailed account of kratom's adverse cardiovascular effects and cardiotoxicity risk, based on in vitro studies, poison center reports, coroner and autopsy reports, clinical case reports, and clinical studies. Methods: An electronic search was conducted to identify all research articles published in English from 1950 to 2021 using the major research databases, such as Google Scholar, Web of Science, PubMed, Scopus, Mendeley, EMBASE, Cochrane Library, and Medline. We then analyzed the literature's discussion of adverse cardiovascular effects, toxicity, and mortality related to kratom use. Results: Our findings revealed that, although in vitro studies have found kratom preparations' most abundant alkaloid-mitragynine-to cause a prolonged QTc interval and an increased risk of torsades de pointes, a clinical study examining humans' regular consumption of kratom did not report such a risk. However, this latter study did show that regular kratom use could induce an increased QTc interval in a dose-dependent manner. A few case reports also highlighted that kratom consumption is associated with ventricular arrhythmia and cardiopulmonary arrest, but this association could have ensued when kratom was co-administered with another substance. Similarly, analyses of national poison data showed that kratom's most common adverse acute cardiovascular effects include tachycardia and hypertension. Meanwhile, coroner and autopsy reports indicated that kratom's cardiovascular sequelae encompass coronary atherosclerosis, myocardial infarction, hypertensive cardiovascular disease, left ventricular hypertrophy, cardiac arrhythmia, cardiomegaly, cardiomyopathy, focal band necrosis in the myocardium, and myocarditis. Given the available data, we deduced that all cardiac eventualities reported in the literature could have been compounded by polysubstance use and unresolved underlying medical illnesses. Conclusion: Although kratom use has been associated with death and cardiotoxicity, especially at higher doses and when associated with other psychoactive drugs, the dearth of data and methodological limitations reported in existing studies do not allow a definitive conclusion, and further studies are still necessary to address this issue.

Assessment of Cardiovascular Functioning Among Regular Kratom (Mitragyna speciosa Korth) Users: A Case Series

Multiorgan toxicities have been extensively reported in kratom (Mitragyna speciosa Korth) users in Western countries but not in Southeast Asia. Existing literature argued that this discrepancy may be due to underreporting of kratom-related toxicity cases in Southeast Asia. Hence, this case series filled the research gap by clinically assessing the cardiovascular functioning and serum mitragynine level of regular kratom users in its traditional settings in Malaysia. Nine regular kratom users without history of polysubstance use were recruited from the same community via snowball sampling and were subjected to electrocardiogram (ECG) and echocardiogram assessments. Serum mitragynine analysis was also performed by solid-phase extraction and liquid chromatography-tandem mass spectrometry. The mean serum mitragynine level was 10.3 mg/L (SD = 6.9) and ranged from 2.5 mg/L to 22.4 mg/L. Those who consumed an average daily quantity of four or more glasses of brewed kratom juice (p = 0.045) and those who had prolonged QTc intervals (p = 0.017) had significantly higher serum mitragynine level. Echocardiographic findings of all the respondents were normal except one reported left ventricular hypertrophy and another had trivial tricuspid regurgitation with pulmonary artery systolic pressure (PASP) of 10 + 5 mmHg. Regular kratom use without concomitant use of other illicit substances may not provoke any risk of cardiovascular impairment or toxicity except for prolonged QTc interval, which appeared to be dose dependent. However, as this study was limited by a small sample size, future studies with larger sample size are warranted to confirm our findings.

Kratom Ingestion and Emergency Care: Summary and a Case Report

Kratom ingestion for its psychotropic effect or to self-treat opioid withdrawal symptoms has increased over the last 10 years in the United States. Although mild adverse effects have been observed in users, reports of respiratory failure and shock after kratom consumption remain rare. In this case, a 35-year-old man initially presented to the emergency department with profound circulatory shock, metabolic acidosis, hypoxia, and symptoms of autonomic nervous system dysfunction. The patient required vasopressor support, multiregimen sedation and rapid sequence intubation, mechanical ventilation, and emergent hemodialysis. Within 72 hours, the patient's condition stabilized, and he was extubated. The patient reported regular consumption of large quantities of kratom as well as injection of heroin and cocaine. In this report, a rare clinical presentation after kratom ingestion is described.

Kratom exposures among older adults reported to U.S. poison centers, 2014-2019

BACKGROUND

In recent years, use of the herbal supplement kratom has increased in the United States. The reasons for use include pain relief, particularly as a substitute for opioids.

OBJECTIVES

To describe epidemiologic trends in kratom-related exposures among older adults reported to U.S. poison centers.

DESIGN

Retrospective analysis of American Association of Poison Control Center's National Poison Data System (NPDS).

SETTING

Data from all U.S. poison centers from 2014 to 2019 were examined.

PARTICIPANTS

Kratom exposure cases involving adults aged 18 and older. Kratom cases were identified by product and NPDS generic codes. Non-human and information-only calls were excluded. Data were examined for all calls for exposures among adults, with a focus on older adults aged 60-69 years and above 70 years.

MEASUREMENTS

Descriptive analyses were used to characterize individual demographic, exposure information, clinical effects, and medical outcomes associated with kratom exposures among older adults. Comparisons across age groups (18-59, 60-69, and 70+ years) were made using Fisher's exact tests.

RESULTS

Among 3484 kratom-related exposures reported between 2014 and 2019, 4.6% (n = 162) were among adults over 60 years. The number of kratom-related exposures increased over time. Most cases originated with calls from healthcare facilities (81.1%) and involved kratom as a single ingestant (63.0%). The reason for most ingestions was intentional (74.5%). One in five exposures among adults aged 70 and older involved an adverse reaction (e.g., drug interaction; 21.9%), compared with 12.3% among ages 60-69 and 9.6% among ages 18-59 years. Neurological and cardiovascular clinical effects were observed. Twenty-three deaths were observed among older adults.

CONCLUSION

Healthcare providers and older adult patients should be aware of the potential risks of kratom use, including medication interactions and falls. When reviewing medication lists, providers should query this population for all medications and substances being used, especially in people being treated for pain.

The Causes of Death and Pathological Findings of Kratom Users: A 5-Year Retrospective Analysis

ABSTRACT

Kratom is a psychoactive substance in Thailand. The major psychoactive chemical component of Kratom is mitragynine. This study aims to elucidate the characteristics and pathologies of autopsied cases where mitragynine was present and quantify the amounts of mitragynine. The autopsy reports in which the blood samples were positive for mitragynine were selected in Ramathibodi Hospital between January 2015 and December 2019. Data from autopsy reports comprised sex, age, circumstances of death, pathological findings, other substances, causes of death, and mitragynine concentrations. Mitragynine was quantitatively analyzed using liquid chromatography-mass spectrometry/mass spectrometry. Twenty-four cases from 2160 autopsy cases were found to be positive for mitragynine. The most commonly observed pathological findings were pulmonary edema (7 cases) and coronary atherosclerosis (6 cases). Antihistamine (8 cases), ethanol (4 cases), and amphetamine (4 cases) were commonly found. The mitragynine concentrations were 0.0035 to 3.6 mg/L (median 0.069). One interesting case involved a 43-year-old man whose pathological findings showed chronic asthma with a high concentration of mitragynine in the blood (3.6 mg/L), although no other substances were detected. In conclusion, the use of mitragynine may be a direct or indirect cause of death, whereas the lethal concentration has yet to be clearly determined.

Unusual Presentation of Kratom Overdose With Rhabdomyolysis, Transient Hearing Loss, and Heart Failure

Kratom mainly grows in Southeast Asia. It is widely used for pain management and opioid withdrawal, which is available online for cheaper prices. Alkaloids extracted from kratom such as mitragynine and 7-hydroxy mitragynine exhibit analgesic properties by acting through µ receptors. Commonly reported side effects of kratom include hypertension, tachycardia, agitation, dry mouth, hallucinations, cognitive and behavioral impairment, cardiotoxicity, renal failure, cholestasis, seizures, respiratory depression, coma, and sudden cardiac death from cardiac arrest. Rhabdomyolysis is a less commonly reported lethal effect of kratom. Limited information is available in the literature. In this article, we present a case of a 45-year-old female who is overdosed with kratom and presented with lethargy, confusion, transient hearing loss, and right lower extremity swelling and pain associated with weakness who was found to have elevated creatinine phosphokinase. She was diagnosed with rhabdomyolysis, compartment syndrome, multiorgan dysfunction including acute kidney injury, liver dysfunction, and cardiomyopathy. She underwent emergent fasciotomy and required hemodialysis. Her renal and liver function subsequently improved. We described the case and discussed pharmacology and adverse effects of kratom toxicity with a proposed mechanism and management. We conclude that it is essential for emergency physicians, internists, intensivists, cardiologists, and nephrologists to be aware of these rare manifestations of kratom and consider a multidisciplinary approach.

Report of ventricular fibrillation in a 44-year-old man using kratom

Kratom is an unregulated kappa-opioid receptor agonist available for order on the internet that is used as a remedy for chronic pain. We present a case of a middle-aged man who suffered a cardiac arrest in the setting of 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.

Temperature and pH-Dependent Stability of Mitragyna Alkaloids

Mitragynine (MG) is the principal psychoactive alkaloid in kratom. The drug produces a variety of dose-dependent effects that appeal to recreational drug users and individuals seeking therapeutic benefits in the absence of medical supervision. In light of documented intoxications, hospitalizations and fatalities, MG and other alkaloids from Mitragyna speciosa are of growing importance to the forensic toxicology community. However, the chemical stability of these compounds has not been thoroughly described. In this report, the stability of MG, 7-hydroxymitragynine (MG-OH), speciociliatine (SC), speciogynine (SG) and paynantheine (PY) are investigated. Short-term stability of the Mitragyna alkaloids was determined over a range of pH (2-10) and temperature (4-80°C) over 8 hours. Liquid chromatography--quadrupole/time-of-flight mass spectrometry was used to estimate half-lives and identify degradation products where possible. The stability of MG and other alkaloids was highly dependent on pH and temperature. All of the Mitragyna alkaloids studied were acid labile. Under alkaline conditions, MG undergoes chemical hydrolysis of the methyl ester to produce 16-carboxymitragynine. MG-OH was the most unstable alkaloid studied, with significant drug loss at 8 hours experienced at temperatures of 40°C and above. No significant drug losses were observed for MG in aqueous solution (pH 2-10) at 4, 20 or 40°C. Diastereoisomers of MG (SC and SG) demonstrated even greater stability. These findings are discussed within the context of the identification of Mitragyna alkaloids in toxicological specimens.

Pharmacologic and clinical assessment of kratom: An update

PURPOSE

This article presents updated information on kratom (Mitragyna speciosa), a natural opioid with stimulant properties that is currently sold in the United States without a prescription.

SUMMARY

Kratom exerts opioid and alpha-2 agonistic effects, as well as anti-inflammatory and mild stimulant effects. Respiratory depression has not been commonly reported, but kratom does cause a host of adverse effects. While kratom may have a role in patients who are in chronic pain or dependent on opioid painkillers or heroin, this needs to be established in clinical trials. Kratom may have drug interactions as both a cytochrome P-450 system substrate and inhibitor. Kratom does not appear in normal drug screens and, especially when ingested with other substances of abuse, may not be recognized as an agent of harm. There are numerous cases of death in kratom users, but many involved polypharmaceutical ingestions. There are assessments where people have been unable to stop using kratom therapy and withdrawal signs/symptoms occurred in patients or their newborn babies after kratom cessation. Both banning and failure to ban kratom places people at risk; a middle-ground alternative, placing it behind the pharmacy counter, might be useful.

CONCLUSION

Kratom has a unique pharmacologic profile that might offer advantages over other opioids, but its high abuse liability, potential for drug interactions and adverse events, and inadequate research into the balance of benefits to harm are concerning. There is mounting information on the adverse events associated with kratom use and potential treatments that can be useful to clinicians.

CYP450-Mediated Metabolism of Mitragynine and Investigation of Metabolites in Human Urine

Mitragyna speciosa (Kratom) has emerged as a recreational drug and a substance of medicinal intrigue. Although the drug was initially used recreationally for its sedating and euphoric effects, more recently its use has been associated with the non-medically supervised treatment of opioid abstinence syndrome. Mitragynine is the principal pharmacologically active alkaloid in kratom. Although metabolites of mitragynine have been identified, the cytochrome P450 (CYP450) enzymes responsible for its biotransformation are still under investigation. The goal of this study was to contribute further knowledge regarding CYP450 activity as it relates to mitragynine. Recombinant cytochrome P450 enzymes (rCYPs) were used to investigate the isoforms involved in its metabolism. Biotransformational products were identified using liquid chromatography-quadrupole/time of flight-mass spectrometry. Four rCYP enzymes (2C18, 2C19, 2D6 and 3A4) were found to contribute to the metabolism of mitragynine. 7-Hydroxymitragynine (which has an affinity for the mu-opioid receptor >10-folds that of morphine) was produced exclusively by 3A4. 9-O-demethylmitragynine, the most abundant metabolite in vitro (and the most prevalent metabolite in urine among kratom users) was produced by 2C19, 3A4 and 2D6. 16-Carboxymitragynine was produced by rCYPs 2D6, 2C19 and 2C18. 2C19 was solely responsible for the formation of 9-O-demethyl-16-carboxymitragynine. In vitro rCYP studies were compared with phase I metabolites in urine from cases involving mitragynine.

Can Kratom (Mitragyna speciosa) Alleviate COVID-19 Pain? A Case Study

Among the symptoms of COVID-19 fever, general malaise, pain and aches, myalgia, fatigue, and headache can affect the quality of life of patients, even after the end of the acute phase of the infection and can be long lasting. The current treatment of these symptoms, also because COVID-19 patients have been asked not to use non-steroidal anti-inflammatory drugs (NSAIDs), in particular ibuprofen are often unsatisfactory. Among the above mentioned symptoms malaise and fatigue seem the most difficult to treat. In this case report we describe the use of kratom (Mitragyna speciosa) by a patient with confirmed COVID-19 infection. What we observed was a fast and sustained relieve of the above mentioned symptoms.

Investigation of the Adrenergic and Opioid Binding Affinities, Metabolic Stability, Plasma Protein Binding Properties, and Functional Effects of Selected Indole-Based Kratom Alkaloids

Selected indole-based kratom alkaloids were evaluated for their opioid and adrenergic receptor binding and functional effects, in vivo antinociceptive effects, plasma protein binding, and metabolic stability. Mitragynine, the major alkaloid in Mitragyna speciosa (kratom), had higher affinity at opioid receptors than at adrenergic receptors while the vice versa was observed for corynantheidine. The observed polypharmacology of kratom alkaloids may support its utilization to treat opioid use disorder and withdrawal.

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.

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.

Fatal combination of mitragynine and quetiapine - a case report with discussion of a potential herb-drug interaction

Kratom is a plant with dose-dependent mixed stimulant and opioid properties whose pharmacologic characteristics and social impact continue to be described. The main active isolate of kratom is mitragynine, an indole-containing alkaloid with opioid-like effects. Kratom toxicity and kratom-associated fatalities have been described, including those in association with additional drugs. In this paper we describe the case of a 27-year-old man who was found deceased with a toxic blood concentration of quetiapine in conjunction with the qualitative presence of mitragynine. Investigative and autopsy findings suggested perimortem hyperthermia and seizure-like activity. Kratom toxicity and kratom-associated fatalities are being increasingly reported. Experiments with kratom extracts have shown inhibitory effects upon hepatic CYP enzymes, leading to previous speculation of the potential for clinically significant interactions between kratom and a wide array of medications. Herein is described a fatal case of quetiapine toxicity complicated by mitragynine use. The potential ability of mitragynine to alter the pharmacokinetics of a prescription medication via inhibition of its hepatic metabolism is discussed.

To Test or Not To Test?: The Value of Toxicology in a Delayed Overdose Death

A case demonstrating the necessity of thorough death investigation processes where toxicology plays an active role is presented. A 33-year-old white man presented to the emergency room in respiratory distress after an overdose episode where he was revived on the scene by fire rescue. His condition continued to deteriorate and he expired 6 days after the initial incident. No admission specimens were available for testing; however, there were specimens drawn 4 and 5 days after the incident. Drug paraphernalia from the scene was obtained by the laboratory through collaboration with local law enforcement. Drug paraphernalia was initially tested in the laboratory and after obtaining the results, the antemortem and postmortem specimens were tested identifying mitragynine and U-47700, among other drugs. These results indicate the value in obtaining and testing drug paraphernalia, and the value of testing antemortem specimens even in the event of a delay.