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.

Fatality of 33-Year-Old Man Involving Kratom Toxicity.

Kratom is an herbal product commonly used for its effects which are similar to opioids and stimulants. Few studies demonstrate the dangers and lethality of Kratom, and most fatalities from Kratom involve other abused substances. In the current case report, a 33-year-old white man with a known history of opioid abuse and mental illnesses was found unresponsive in his basement with no obvious signs of trauma. After resuscitative efforts, he was pronounced dead and taken for autopsy evaluation. Blood from the inferior vena cava was analyzed for common abused substances. The laboratory toxicology work-up revealed positive findings of caffeine, cotinine, and naloxone with low levels of Δ-9 tetrahydrocannabinol. However, a marked level of mitragynine at 1.9 mg/L was observed, the highest reported to date. Given the facts and evidence, the medical examiner certified the cause of death as "mitragynine toxicity" and the manner of death was classified as an "accident."

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.

Comparative Pharmacokinetics of Mitragynine after Oral Administration of Mitragyna speciosa (Kratom) Leaf Extracts in Rats.

Kratom (Mitragyna speciosa) has been examined for its opioid activity, especially for the treatment of opioid withdrawal and pain. Mitragynine, the most abundant alkaloid in kratom, is thought to be the major psychoactive alkaloid. An HPLC method was developed for the quantification of mitragynine in kratom leaf extracts. In addition, a multiple reaction mode based UPLC-MS/MS method was developed and validated for the quantification of mitragynine in rat plasma. Pharmacokinetic studies were performed by comparing a single intravenous dose of mitragynine (5 mg/kg, mitragynine hydrochloride) to a single oral dose of mitragynine (20 mg/kg, mitragynine hydrochloride), lyophilized kratom tea, and the organic fraction of the lyophilized kratom tea at an equivalent mitragynine dose of 20 mg/kg in rats. After intravenous administration, mitragynine exhibited a biexponential decrease in the concentration-time profile, indicating the fast distribution of mitragynine from the systemic circulation or central compartment to the peripheral compartments. Mitragynine hydrochloride, lyophilized kratom tea, and the lyophilized kratom tea organic fraction were dosed orally and the absolute oral bioavailability of mitragynine in rats was found to be 1.5- and 1.8-fold higher than that of mitragynine dosed alone. The results provide evidence that an equivalent oral dose of the traditional preparation (lyophilized kratom tea) and formulated/manufactured products (organic fraction) of kratom leaves provide better systemic exposure of mitragynine than that of mitragynine dosed alone.

Suspected Driving Under the Influence Case Involving Mitragynine.

Mitragynine is a novel psychoactive substance (NPS) that has emerged as a designer opioid being distributed on the street. Mitragynine, also known as kratom, has dose-dependent pharmacological effects and possesses both stimulant-like and sedative effects due to dual-binding of α-adrenergic and µ-opioid receptors. This herbal remedy readily available online has caused adverse effects including tachycardia, agitation, tremors, hallucination and death; however, this is the first reported suspected driving under the influence case involving mitragynine. Additional testing outside of the normal routine protocol for suspected impaired driving cases was performed based on the admission of kratom use from the suspect to the drug recognition expert (DRE) officer. Based on the evaluation, the DRE officer concluded that the driver was under the influence of a central nervous system stimulant and cannabis. An alkaline drug screen identified mitragynine in a 37-year-old female driver who was suspected of driving under the influence after nearly striking an oncoming vehicle. A blood amphetamine concentration was quantified at 0.052 mg/L and mitragynine and citalopram were reported qualitatively. The goal of this case study is to provide demographic history, adverse effects and a DRE evaluation in a driver known to have abused mitragynine.

Mitragynine 'Kratom' related fatality: a case report with postmortem concentrations.

A 24-year-old man whose medical history was significant for alcohol abuse and depression was found unresponsive in bed. He had several prior suicide attempts with 'pills' and had also been hospitalized for an accidental overdose on a previous occasion. Autopsy findings were unremarkable apart from pulmonary edema and congestion, and urinary retention. Postmortem peripheral blood initially screened positive for mitragynine 'Kratom' (by routine alkaline drug screen by gas chromatography-mass spectrometry, GC-MS), which was subsequently confirmed by a specific GC-MS selective ion mode analysis following solid-phase extraction. Concentrations were determined in the peripheral blood (0.23 mg/L), central blood (0.19 mg/L), liver (0.43 mg/kg), vitreous (<0.05 mg/L), urine (0.37 mg/L) and was not detected in the gastric. Therapeutic concentrations of venlafaxine, diphenhydramine and mirtazapine were also detected together with a negligible ethanol of 0.02% (w/v). The results are discussed in relation to previous cases of toxicity, and the lack of potential for mitragynine postmortem redistribution.

Development and validation of a UPLC-MS/MS method for the determination of 7-hydroxymitragynine, a µ-opioid agonist, in rat plasma and its application to a pharmacokinetic study.

A simple, sensitive and specific ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to determine the concentrations of 7-hydroxymitragynine in rat plasma. Following a single-step liquid-liquid extraction of plasma samples using chloroform, 7-hydroxymitragynine and the internal standard (tryptoline) were separated on an Acquity UPLC(TM) BEH C18 (1.7 µm, 2.1 × 50 mm) column using an isocratic elution at a flow rate of 0.2 mL/min. The mobile phase consisted of 0.1% acetic acid in water and 0.1% acetic acid in acetonitrile (10:90, v/v). The run time was 2.5 min. The analysis was carried out under the multiple reaction-monitoring mode using positive electrospray ionization. Protonated ions [M + H](+) and their respective product ions were monitored at the following transitions: 415 → 190 for 7-hydroxymitragynine and 173 → 144 for the internal standard. The calibration curve was linear over the range of 10-4000 ng/mL (r(2) = 0.999) with a lower limit of quantification of 10 ng/mL. The extraction recoveries ranged from 62.0 to 67.3% at concentrations of 20, 600 and 3200 ng/mL). Intra- and inter-day assay precisions (relative standard deviation) were <15% and the accuracy was within 96.5-104.0%. This validated method was successfully applied to quantify 7-hydroxymitragynine in rat plasma following intravenous administration.

Identification of novel psychoactive drug use in Sweden based on laboratory analysis--initial experiences from the STRIDA project.

AIM: The study aimed to collect information concerning the increasing use of new psychoactive substances, commonly sold through online shops as 'Internet drugs' or 'legal highs', or in terms of masked products such as 'bath salts' and 'plant food'. METHODS: The Karolinska Institutet and Karolinska University Laboratory and the Swedish Poisons Information Centre have initiated a project called 'STRIDA' aiming to monitor the occurrence and trends of new psychoactive substances in Sweden, and collect information about their clinical symptoms, toxicity and associated health risks. A liquid chromatographic-tandem mass spectrometric (LC-MS/MS) multi-component method has been developed, currently allowing for the determination of > 80 novel psychoactive compounds or metabolites thereof. This study focused mainly on the particular drug substances identified and the population demographics of the initial STRIDA cases. RESULTS: In urine and/or blood samples obtained from 103 consecutive cases of admitted or suspected recreational drug intoxications in mostly young subjects (78% were ≤ 25 years, and 81% were males) presenting at emergency departments all over the country, psychoactive substances were detected in 82%. The substances comprised synthetic cannabinoids ('Spice'; JWH analogues), substituted cathinones ('bath salts'; e.g. butylone, MDPV and methylone) and tryptamines (4-HO-MET), plant-based substances (mitragynine and psilocin), as well as conventional drugs-of-abuse. In 44% of the cases, more than one new psychoactive substance, or a mixture of new and/or conventional drugs were detected. CONCLUSION: The initial results of the STRIDA project have documented use of a broad variety of new psychoactive substances among mainly young people all over Sweden.

A drug fatality involving Kratom.

A 17-year-old white man who showed no obvious signs of trauma was found unresponsive in bed and was pronounced dead at the scene. The decedent had a documented history of heroin abuse and chronic back pain and reportedly self-medicated with Kratom (mitragynine). The autopsy was remarkable only for pulmonary congestion and edema and a distended bladder, both of which are consistent with, though not diagnostic of, opiate use. A laboratory work-up revealed therapeutic levels of over-the-counter cold medications and benzodiazepines. However, of interest was a level of mitragynine at 0.60 mg/L. Given the facts of the case, the Medical Examiner certified the cause of death as "possible Kratom toxicity" and the manner of death was classified as "accident."

Intrahepatic cholestasis following abuse of powdered kratom (Mitragyna speciosa).

INTRODUCTION: Kratom (Mitragyna speciosa) is a common medical plant in Thailand and is known to contain mitragynine as the main alkaloid. According to an increase in published reports and calls at German poison control centers, it has been used more frequently as a drug of abuse in the western hemisphere during the last couple of years. Despite this increase, reports of severe toxicity are rare within the literature. CASE REPORT: We describe a case of a young man who presented with jaundice and pruritus after intake of kratom for 2 weeks in the absence of any other causative agent. Alkaloids of M. speciosa were detected in the urine. CONCLUSION: While M. speciosa is gaining in popularity among illicit drug users, its adverse effects remain poorly understood. This is the first published case of intrahepatic cholestasis after kratom abuse.

Unintentional fatal intoxications with mitragynine and O-desmethyltramadol from the herbal blend Krypton.

The leaves of Kratom, a medicinal plant in Southeast Asia, have been used as an herbal drug for a long time. At least one of the alkaloids present in Kratom, mitragynine, is a mu-receptor agonist. Both Kratom and an additional preparation called Krypton are available via the internet. It seems to consist of powdered Kratom leaves with another mu-receptor agonist, O-desmethyltramadol, added. O-Desmethyltramadol is an active metabolite of tramadol, a commonly prescribed analgesic. We present nine cases of intoxication, occurring in a period of less than one year, where both mitragynine and O-desmethyltramadol were detected in the postmortem blood samples. Neither tramadol nor N-desmethyltramadol was present in these samples, which implies that the ingested drug was O-desmethyltramadol. The blood concentrations of mitragynine, determined by ultra-performance liquid chromatography-tandem mass spectrometry, ranged from 0.02 to 0.18 µg/g, and O-desmethyltramadol concentrations, determined by gas chromatography with nitrogen-specific detection, ranged from 0.4 to 4.3 µg/g. We believe that the addition of the potent mu-receptor agonist O-desmethyltramadol to powdered leaves from Kratom contributed to the unintentional death of the nine cases presented and conclude that intake of Krypton is not as harmless as it often is described on internet websites.

A drug toxicity death involving propylhexedrine and mitragynine.

A death involving abuse of propylhexedrine and mitragynine is reported. Propylhexedrine is a potent α-adrenergic sympathomimetic amine found in nasal decongestant inhalers. The decedent was found dead in his living quarters with no signs of physical trauma. Analysis of his computer showed information on kratom, a plant that contains mitragynine, which produces opiumlike effects at high doses and stimulant effects at low doses, and a procedure to concentrate propylhexedrine from over-the-counter inhalers. Toxicology results revealed the presence of 1.7 mg/L propylhexedrine and 0.39 mg/L mitragynine in his blood. Both drugs, as well as acetaminophen, morphine, and promethazine, were detected in the urine. Quantitative results were achieved by gas chromatography-mass spectrometry monitoring selected ions for the propylhexedrine heptafluorobutyryl derivative. Liquid chromatography-tandem mass spectrometry in multiple reactions monitoring mode was used to obtain quantitative results for mitragynine. The cause of death was ruled propylhexedrine toxicity, and the manner of death was ruled accidental. Mitragynine may have contributed as well, but as there are no published data for drug concentrations, the medical examiner did not include mitragynine toxicity in the cause of death. This is the first known publication of a case report involving propylhexedrine and mitragynine.

Determination of mitragynine in plasma with solid-phase extraction and rapid HPLC-UV analysis, and its application to a pharmacokinetic study in rat.

A new solid phase extraction method for rapid high performance liquid chromatography-UV determination of mitragynine in plasma has been developed. Optimal separation was achieved with an isocratic mobile phase consisting of acetonitrile-ammonium acetate buffer, 50 mM at pH 5.0 (50:50, v/v). The method had limits of detection and quantification of 0.025 and 0.050 microg/mL, respectively. The method was accurate and precise for the quantitative analysis of mitragynine in human and rat plasma with within-day and between-day accuracies between 84.0 and 109.6%, and their precision values were between 1.7 and 16.8%. Additional advantages over known methods are related to the solid phase extraction technique for sample preparation which yields a clean chromatogram, a short total analysis time, requires a smaller amount of plasma samples and has good assay sensitivity for bioanalytical application. The method was successfully applied in pharmacokinetic and stability studies of mitragynine. In the present study, mitragynine was found to be fairly stable during storage and sample preparation. The present study showed for the first time the detailed pharmacokinetic profiles of mitragynine. Following intravenous administration, mitragynine demonstrated a biphasic elimination from plasma. Oral absorption of the drug was slow, prolonged and was incomplete, with a calculated absolute oral bioavailability value of 3.03%. The variations observed in previous pharmacokinetic studies after oral administration of mitragynine could be attributed to its poor bioavailability rather than to the differences in assay method, metabolic saturation or mitragynine dose.

Determination of mitragynine in rat plasma by LC-MS/MS: application to pharmacokinetics.

This study used for the first time LC-MS/MS for the analysis of mitragynine (MIT), a mu-opioid agonist with antinociceptive and antitussive properties, in rat plasma. Mitragynine and the internal standard (amitriptyline) were extracted from plasma with hexane-isoamyl alcohol and resolved on a Lichrospher RP-SelectB column (9.80 and 12.90 min, respectively). The quantification limit was 0.2 ng/mL within a linear range of 0.2-1000 ng/mL. The method was applied to quantify mitragynine in plasma samples of rats (n=8 per sampling time) treated with a single oral dose of 20 mg/kg. The following pharmacokinetic parameters were obtained (mean): maximum plasma concentration: 424 ng/mL; time to reach maximum plasma concentration: 1.26 h; elimination half-life: 3.85 h, apparent total clearance: 6.35 L/h/kg, and apparent volume of distribution: 37.90 L/kg.

A high-performance liquid chromatographic method for determination of mitragynine in serum and its application to a pharmacokinetic study in rats.

A simple HPLC technique for determining mitragynine levels in serum was developed. The separation system consisted of a C18 column heated to 35 degrees C, a methanol-water (80:20, v/v) mobile phase, a flow rate of 0.8 mL/min and detection in the ultraviolet at 225 nm. Mitragynine, with a retention time of 10.09 min, was well resolved from any interferences in human serum and the internal standard peak. The calibration curve was linear from 0.1 to 10 microg/mL (r = 0.9995). Extraction of mitragy-nine from alkalinized serum using diethyl ether gave a high recovery (>or=85%). The intra- and inter-day precisions of the method were 4.29-5.88%RSD and 7.06-8.45%RSD, respectively. The accuracy ranged from -9.54 to +0.67%DEV. The limit of detection was 0.03 microg/mL and the lower limit of quantification was 0.1 microg/mL. Mitragynine in the stock solution was stable during 30 days of storage at 4 degrees C. This method was successfully applied to determine the pharmacokinetic characteristics of mitragynine levels in the serum of rats after it was administered orally.