The internet market for Kratom, an opioid alternative and variably legal recreational drug

Associations Between Kratom-Related State Policy Environments and Kratom Use in a Nationally Representative Population in the United States

Limited research has resulted in conflicting views on the risks versus benefits associated with kratom use. Despite no federal policy in the United States, individual states have implemented diverging policies through kratom bans, and legalization and regulation through Kratom Consumer Protection Acts (KCPAs). The Survey of Non-Medical Use of Prescription Drugs (NMURx) Program employs nationally-representative, repeated cross-sectional surveys on drug use. In 2021, weighted prevalence of past-12 month kratom use was compared across three state legal frameworks: no overarching state policy, KCPAs, and state bans. There was lower estimated prevalence of kratom use in banned states (prevalence: 0.75% (0.44, 1.06) relative to states with a KCPA (1.20% (0.89, 1.51)), and relative to states with no policies (1.04% (0.94, 1.13), though odds of use were not significantly associated with policy type. Kratom use was significantly associated with medicated treatment for opioid use disorder. While there were observed differences in the prevalence of past-12 month kratom use by state policy type, low uptake mitigated meaningful distinctions by limiting statistical precision, and potentially confounding effects, such as accessibility online. Future kratom-related policy decisions should be informed through evidence-based research.

Human Mitragynine and 7-Hydroxymitragynine Pharmacokinetics after Single and Multiple Daily Doses of Oral Encapsulated Dried Kratom Leaf Powder

Kratom leaves, consumed by millions worldwide as tea or ground leaf powder, contain multiple alkaloids, with mitragynine being the most abundant and responsible for most effects. Mitragynine is a partial µ-opioid receptor agonist and competitive antagonist at κ- and δ-opioid receptors; however, unlike morphine, it does not activate the β-arrestin-2 respiratory depression pathway. Due to few human mitragynine data, the largest randomized, between-subject, double-blind, placebo-controlled, dose-escalation study of 500-4000 mg dried kratom leaf powder (6.65-53.2 mg mitragynine) was conducted. LC-MS/MS mitragynine and 7-hydroxymitragynine plasma concentrations were obtained after single and 15 daily doses. Mitragynine and 7-hydroxymitragynine Cmax increased dose proportionally, and AUC was slightly more than dose proportional. The median mitragynine Tmax was 1.0-1.3 h after single and 1.0-1.7 h after multiple doses; for 7-hydroxymitragynine Tmax, it was 1.2-1.8 h and 1.3-2.0 h. Steady-state mitragynine concentrations were reached in 8-9 days and 7-hydroxymitragynine within 7 days. The highest mean mitragynine T1/2 was 43.4 h after one and 67.9 h after multiple doses, and, for 7-hydroxymitragynine, it was 4.7 and 24.7 h. The mean 7-hydroxy-mitragynine/mitragynine concentration ratios were 0.20-0.31 after a single dose and decreased (0.15-0.21) after multiple doses. These mitragynine and 7-hydroxymitragynine data provide guidance for future clinical kratom dosing studies and an interpretation of clinical and forensic mitragynine and 7-hydroxymitragynine concentrations.

Kratom Retail Availability in Fort Worth, Texas

Kratom use is associated with cannabis use, so retail availability may also be related. Kratom and Delta-8 THC (a psychoactive cannabis product) are federally unregulated, marketed as "natural," and often used for pain relief and/or relaxation. Kratom may have greater retail availability in more socioeconomically deprived areas because harmful substances are frequently marketed to lower-income communities. This study examined kratom retail availability in Fort Worth, Texas. Locations with alcohol, tobacco, and/or CBD licenses were called in July 2022: 1,025/1,223 (84%) answered the phone. T-tests examined potential differences in socioeconomic deprivation scores surrounding outlets by whether they sold kratom. Cross-tabulations examined overlap in kratom and Delta-8 THC availability. Kratom was available in 6% of locations. Most kratom retailers had a tobacco license (92%). However, most stores with a tobacco license did not sell kratom (14%), whereas most stores with a CBD license did (55%). Kratom availability was not associated with area deprivation scores. Most kratom retailers (95%) sold Delta-8 THC and two-thirds (65%) of Delta-8 THC retailers sold kratom. This study was the first to examine retail availability of kratom. Findings indicate the presence of niche stores specializing in the retail of federally unregulated substances.

Buprenorphine-Naloxone in the Setting of Kratom Withdrawal, Opioid Use Disorder, and Stage IV Lung Adenocarcinoma

Management of cancer-associated pain warrants consideration of many factors, including characterization and etiology of the pain, socioeconomic factors, medication tolerance, and substance use history. Kratom (Mitragyna speciosa) is an herbal substance with stimulant and analgesic properties that is becoming a popular drug in the United States. In this report, we present a patient with a history of opioid use disorder (OUD) who had been using high doses of kratom to alleviate progressive chest pain and dyspnea secondary to newly diagnosed stage IV lung adenocarcinoma. He underwent kratom withdrawal shortly after his index admission and was reluctant to continue full opioid agonists given his history of OUD and complex living situation. His kratom withdrawal and cancer-associated symptoms were successfully managed with buprenorphine-naloxone. Providers should obtain a careful history of novel substance use such as kratom. Furthermore, buprenorphine-naloxone is a safe and effective option to simultaneously manage kratom withdrawal and cancer-associated pain.

Narrative Review of Kratom, an Emerging Psychoactive Substance With Perianesthetic Implications

Opioid overprescribing, with resultant overdose and death, has led to a national focus on alternative treatments for pain. With the decline in legal access to opioids, kratom has gained popularity as a legal, "natural," and easily accessible nonprescription analgesic for consumers wishing to self-medicate for pain, opioid use disorder, and other mental health conditions. While implications of kratom use in patients with chronic pain and/or opioid use disorder have been published, information on perianesthetic implications is lacking. Anesthesiologists should be informed about kratom, including the potential for unexpected physiologic derangements and adverse drug interactions resulting from complex pharmacologic activity, cytochrome P450 interactions, and common adulterations of the drug that may result in unpredictable clinical effects. This article explores the relevance of kratom to perioperative anesthetic care, including suggestions for anesthesiologists extrapolated from published information in nonoperative settings that may improve patient safety in individuals using kratom.

Associations of Lifetime Nonmedical Opioid, Methamphetamine, and Kratom Use within a Nationally Representative US Sample

Co-use of non-medical opioids (NMO) and methamphetamine is increasing. So too is the use of the psychoactive botanical "kratom," including among people with NMO and methamphetamine use histories. We assessed characteristics associated with respondent groups who reported lifetime methamphetamine and/or kratom use within a nationally representative US sample using 2019 National Survey on Drug Use and Health data from respondents reporting lifetime NMO use (diverted prescription opioids, heroin). Weighted prevalence estimates for demographic, mental health, and substance use outcomes were determined. Logistic regression examined associations between group membership and outcomes. Among this sample of respondents with lifetime NMO use, 67.6% (95% CI = 65.6-69.4%) reported only NMO use; 4.6% (3.9-5.4%) reported NMO+Kratom; 24.7% (22.7-26.7%) reported NMO+Methamphetamine; and 3.2% (2.5-3.9%) reported NMO+Methamphetamine+Kratom. Compared to those in the NMO-only group, the NMO+Kratom group was more likely to report past-year serious mental illness (SMI; OR = 2.27), suicidality (OR = 1.89), and past-month psychological distress (OR = 1.88). The NMO+Methamphetamine+Kratom group was more likely to report past-year SMI (OR = 2.65), past-month psychological distress (OR = 2.06), and unmet mental health needs (OR = 2.03); increased odds for drug injection, opioid withdrawal, and perceived treatment need also emerged. Risk factors were observed for all groups but were greatest among those reporting use of all three substances.

Kratom: History, pharmacology, current user trends, adverse health effects and potential benefits

Kratom (Mitragyna speciosa Korth.) is a tree native to Southeast Asia with dose-dependent stimulant and opioid-like effects. Dried, powdered leaf material is among the kratom products most commonly consumed in the US and Europe, but other formulations also exist including enriched extracts, resins, tinctures, and edibles. Its prevalence in the US remains debated and the use pattern includes self-treatment of mood disorders, pain, and substance use disorders. Most of the adverse effects of kratom and its alkaloid mitragynine have been reported in the literature as case reports or part of surveys necessitating confirmation by clinical trials. Toxicities associated with kratom consumption have focused on hepatic, cardiac, and CNS effects with the potential to cause fatalities primarily as part of polydrug exposures. Kratom may also present with drug-drug interactions primarily through CYP 3A4 and 2D6 inhibition, although the clinical significance remains unknown to date. The variability in composition of commercially available kratom products complicates generalization of findings and requires further investigation by employing clinical trials. Healthcare professionals should remain cautious in counseling patients on the use of kratom in a therapeutic setting.

Kratom Use Among U.S. Adolescents: Analyses of the 2019 National Survey on Drug Use and Health

BACKGROUND

Kratom (Mitragyna speciosa) is an opioid-like psychoactive substance not approved by the U.S. Food and Drug Administration that could be used due to its euphoric, stimulant, and analgesic effects. Kratom is gaining popularity in the U.S. and becoming a reason of concern among pediatricians.

METHODS

Data from the 2019 National Survey on Drug Use and Health were analyzed to estimate the prevalence and identify correlates of lifetime and past 12-month kratom use among 13,397 U.S. adolescents. Multivariable logistic regression models were conducted to assess the associations of interest.

RESULTS

Lifetime and past 12-month prevalence of kratom use was .44% (95% confidence interval [CI] .32-.60) and .27% (95% CI .18-.40), respectively. Past 12-month cigarette use was associated with lifetime kratom use (adjusted odds ratio 2.60, 95% CI 1.07-6.35). Past 12-month cannabis use was associated with past 12-month kratom use (adjusted odds ratio 2.48, 95% CI 1.15-5.35).

CONCLUSIONS

This first report on the epidemiology of adolescent kratom use provides a baseline to assess kratom use trends in future years and identify potential correlates of use among adolescents.

Pressure Necrosis Requiring Fasciotomy After Kratom Overdose

INTRODUCTION

Kratom (Mitragyna speciosa) is a popular plant-based extract that has dose-dependent stimulatory and sedative effects. It has been used for self-treatment of opioid withdrawal and can result in seizures, hepatotoxicity, and infectious complications from bacterial contamination. Reports of morbidity and mortality associated with Kratom may be confounded by coingestants. We report a case of severe rhabdomyolysis and pressure necrosis leading to fasciotomy in a patient who was using Kratom.

CASE REPORT

A 31-year-old male with substance use presented to the emergency department after loss of consciousness for 6 hours after smoking Kratom. He was found to have rhabdomyolysis, acute renal and hepatic injury, and electrolyte disturbances. No ethanol was detected, and urine drug screen was negative. Over the next 3 hours, the patient developed signs of compartment syndrome and he was transferred to the operating room for fasciotomy. He required continuous renal replacement therapy for 48 hours and his labs and clinical status improved. He was discharged 18 days later. A serum and urine sample from the first day of presentation were analyzed for mitragynine and 7-hydroxymitragynine using an Ultra Performance Liquid Chromatography-Tandem Mass Spectrometer (UPLC-MSMS) method. The serum mitragynine was 5 ng/mL and the urine mitragynine 6 ng/mL.

CONCLUSIONS

Although there are numerous reports of opioids resulting in prolonged periods of immobilization and rhabdomyolysis, this is not commonly reported in Kratom overdoses.This case report highlights the profound sedative effect of Kratom and the potential of pressure necrosis injury resulting in rhabdomyolysis and compartment syndrome requiring fasciotomy.

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.

For Better or Worse: Self-reported Changes in Kratom and Other Substance Use as a Result of the COVID-19 Pandemic

Background:

Kratom is taken to self-treat pain and symptoms of psychiatric disorders, including substance-use disorders (SUDs) and opioid withdrawal. Before COVID-19, kratom use was increasing in the US, however, there are few published data on whether that trend continued during the COVID-19 pandemic, which could have affected kratom use in multiple ways.

Aim:

To examine COVID-19-related changes in kratom use and how these changes were experienced, relative to changes in other commonly used substances.

Methods:

Using Amazon Mechanical Turk, 2615 evaluable surveys were completed between September 2020 and March 2021. Responses from past-month and past-year kratom-using adults (N = 174) indicating changes for the better or worse were examined using generalized linear mixed effects models, and relevant open-text responses (n = 85) were thematically coded.

Results:

For kratom 33% (n = 58) reported a Covid-related increase and 24% (n = 42) reported a Covid-related decrease. Controlling for changes in amount used, alcohol (OR = 5.02), tobacco (OR = 4.72), and nonmedical opioid use (OR = 3.42) were all more likely to have changed for the worse, compared with kratom use. Relative to decreases in kratom use, decreases in alcohol (OR = 3.21) and tobacco (OR = 6.18) use were more likely to be changes for the better. Cannabis use was the only substance to display a probability lower than 50% of being a decrease for the better, and of the increases, cannabis use displayed the highest probability of being for the better.

Conclusions:

Increases in kratom and cannabis use were less likely than alcohol and tobacco to be reported as changes for the worse, and decreases in kratom and cannabis use were more likely than alcohol and tobacco to be reported as changes for the better. These findings indicate that people differently conceptualize their relationships with kratom and cannabis, compared to their relationships with alcohol and tobacco.

Kratom Alkaloids: Interactions With Enzymes, Receptors, and Cellular Barriers

Parallel to the growing use of kratom, there is a wealth of evidence from self-report, preclinical, and early clinical studies on therapeutic benefits of its alkaloids in particular for treating pain, managing substance use disorder, and coping with emotional or mental health conditions. On the other hand, there are also reports on potential health risks concerning kratom use. These two aspects are often discussed in reviews on kratom. Here, we aim to highlight specific areas that are of importance to give insights into the mechanistic of kratom alkaloids pharmacological actions. This includes their interactions with drug-metabolizing enzymes and predictions of clinical drug-drug interactions, receptor-binding properties, interactions with cellular barriers in regards to barrier permeability, involvement of membrane transporters, and alteration of barrier function when exposed to the alkaloids.

Kratom Use Within the Context of the Evolving Opioid Crisis and the COVID-19 Pandemic in the United States

Kratom (Mitragyna speciosa, Korth.) is an evergreen tree that is indigenous to Southeast Asia. When ingested, kratom leaves or decoctions from the leaves have been reported to produce complex stimulant and opioid-like effects. For generations, native populations in Southeast Asia have used kratom products to stave off fatigue, improve mood, alleviate pain and manage symptoms of opioid withdrawal. Despite the long history of kratom use in Asia, it is only within the past 10-20 years that kratom has emerged as an important herbal agent in the United States, where it is being used for the self-treatment of pain, opioid withdrawal symptoms, and mood disorders. The increase in the use of kratom in the United States has coincided with the serious epidemic of opioid abuse and dependence. Since 2015, efforts to restrict access to prescription opioids have resulted in a marked increase in the use of "street" opioids such as heroin and illicit fentanyl. At the same time, many patients with chronic pain conditions or opioid use disorder have been denied access to appropriate medical help. The lack of access to care for patients with chronic pain and opioid use disorder has been magnified by the emergence of the COVID-19 pandemic. In this report, we highlight how these converging factors have led to a surge in interest in kratom as a potential harm reduction agent in the treatment of pain and opioid use disorder.

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.

Refined Prediction of Pharmacokinetic Kratom-Drug Interactions: Time-Dependent Inhibition Considerations

Preparations from the leaves of the kratom plant (Mitragyna speciosa) are consumed for their opioid-like effects. Several deaths have been associated with kratom used concomitantly with some drugs. Pharmacokinetic interactions are potential underlying mechanisms of these fatalities. Accumulating in vitro evidence has demonstrated select kratom alkaloids, including the abundant indole alkaloid mitragynine, as reversible inhibitors of several cytochromes P450 (CYPs). The objective of this work was to refine the mechanistic understanding of potential kratom-drug interactions by considering both reversible and time-dependent inhibition (TDI) of CYPs in the liver and intestine. Mitragynine was tested against CYP2C9 (diclofenac 4'-hydroxylation), CYP2D6 (dextromethorphan O-demethylation), and CYP3A (midazolam 1'-hydroxylation) activities in human liver microsomes (HLMs) and CYP3A activity in human intestinal microsomes (HIMs). Comparing the absence to presence of NADPH during preincubation of mitragynine with HLMs or HIMs, an ∼7-fold leftward shift in IC₅₀ (∼20 to 3 μM) toward CYP3A resulted, prompting determination of TDI parameters (HLMs: K _I , 4.1 ± 0.9 μM; k _inact , 0.068 ± 0.01 min^-1; HIMs: K _I , 4.2 ± 2.5 μM; k _inact , 0.079 ± 0.02 min^-1). Mitragynine caused no leftward shift in IC₅₀ toward CYP2C9 (∼40 μM) and CYP2D6 (∼1 μM) but was a strong competitive inhibitor of CYP2D6 (K _i , 1.17 ± 0.07 μM). Using a recommended mechanistic static model, mitragynine (2-g kratom dose) was predicted to increase dextromethorphan and midazolam area under the plasma concentration-time curve by 1.06- and 5.69-fold, respectively. The predicted midazolam area under the plasma concentration-time curve ratio exceeded the recommended cutoff (1.25), which would have been missed if TDI was not considered. SIGNIFICANCE STATEMENT: Kratom, a botanical natural product increasingly consumed for its opioid-like effects, may precipitate potentially serious pharmacokinetic interactions with drugs. The abundant kratom indole alkaloid mitragynine was shown to be a time-dependent inhibitor of hepatic and intestinal cytochrome P450 3A activity. A mechanistic static model predicted mitragynine to increase systemic exposure to the probe drug substrate midazolam by 5.7-fold, necessitating further evaluation via dynamic models and clinical assessment to advance the understanding of consumer safety associated with kratom use.