Kratom is found in the leaves of Mitragyna speciosa, a tropical tree native to Southeast Asia, but the forms it takes on the consumer market have multiplied far beyond fresh leaves. You can now encounter kratom as dried powder, capsules, tablets, liquid “shots,” gummies, teas, tinctures, nasal sprays, and concentrated extracts sold under dozens of brand names. A newer wave of semi-synthetic products derived from kratom alkaloids has added even more variety, and the safety profile varies considerably depending on which form you use.
The Plant Itself and Its Active Chemistry
Kratom leaves contain a complex mix of alkaloids, with mitragynine being the most abundant. A 2020 analysis identified 19 distinct alkaloids in kratom, including mitragynine and several of its close chemical relatives like speciociliatine, speciogynine, and paynantheine.1Journal of Natural Products. The Chemistry of Kratom [Mitragyna speciosa]: Updated Characterization Data and Methods to Elucidate Indole and Oxindole Alkaloids Another alkaloid, 7-hydroxymitragynine, occurs only in trace amounts in raw leaves but is far more potent at opioid receptors. This distinction between the abundant-but-milder mitragynine and the rare-but-powerful 7-hydroxymitragynine matters enormously when you compare traditional leaf use to modern concentrated products.
These alkaloids interact with opioid receptors in the brain, which accounts for kratom’s pain-relieving and mood-altering effects, but they also affect other receptor systems. Pharmacological research has documented effects on the central nervous system, cardiovascular system, and digestive system.2PubMed Central. A review on Mitragyna alkaloids pharmacology, biosynthesis and biotechnological insights At lower doses, users tend to report stimulant-like effects such as increased energy and alertness. At higher doses, the experience shifts toward sedation and pain relief, more closely resembling opioids.
Traditional Preparations
In Southeast Asia, where kratom grows wild, the plant has been used for generations in a fairly limited number of forms. Workers traditionally chewed fresh leaves or brewed them into tea to combat fatigue, manage pain, or treat diarrhea.3PubMed. Correlations of kratom (Mitragyna speciosa Korth.) tea bag preparations and reported pharmacological effects The alkaloid exposure from chewing a leaf or sipping a cup of brewed tea is relatively modest compared to what concentrated products deliver. When you brew tea, only a fraction of the alkaloids in the leaf material dissolve into the water, which naturally limits the dose.
This traditional use pattern is worth understanding because it looks very different from how most people in Western countries encounter kratom. Dried leaf powder and hydroalcoholic extracts are the more common starting point for consumers outside Southeast Asia, and those preparations deliver a different alkaloid profile than a fresh leaf chewed from the tree.
Vein Colors and What They Mean
If you browse any kratom vendor’s website, you will see products labeled as red vein, green vein, or white vein. These labels refer to the color of the leaf’s central vein, which changes as the leaf matures and may be influenced by drying and processing methods. The marketing around these varieties implies distinctly different effects, and there is some chemistry behind the claims, though the marketing tends to overstate the differences.
Phytochemical analysis of Kalimantan kratom varieties found that all three vein colors share the same core set of alkaloids dominated by mitragynine, but the concentrations differ. Mitragynine content was highest in white vein extracts and lowest in red vein extracts.4Journal of Multidisciplinary Applied Natural Science. Phytochemical Profiling and In Vitro Lipoxygenase Inhibitory Activity of Three Kratom Leaf Varieties by GC–MS, HPLC, and LC–HRMS Meanwhile, a separate review reported that red vein strains generally contain higher concentrations of 7-hydroxymitragynine compared to green and white varieties, while green vein strains tend to have the highest overall alkaloid content.5Proceeding International Seminar of Science and Technology. A Review on Alkaloid Diversity in Mitragyna speciosa (Kratom) In practical terms, the vein color gives you a rough idea of the alkaloid balance, but batch-to-batch variation, growing conditions, and processing techniques can easily override whatever the color label promises.
The Commercial Product Landscape
Walk into a smoke shop, gas station, or specialty store and kratom shows up in a startling range of formats. The most basic products are bags of dried leaf powder or pre-filled capsules. These are essentially ground-up leaves with minimal processing. From there, the market gets more complex.
Concentrated extracts are widely available as liquids, often sold as single-serving “shots” in small bottles. A pharmacokinetic study in rats compared a traditional lyophilized kratom tea to a commercial liquid shot product (OPMS brand) and found that dose-adjusted systemic exposure to the four main alkaloids that reached the bloodstream was roughly 1.6 to 2.4 times higher from the commercial shot.6PubMed Central. Pharmacokinetics of Eleven Kratom Alkaloids Following an Oral Dose of Either Traditional or Commercial Kratom Products in Rats In other words, commercial extract products can deliver meaningfully more alkaloid per serving than traditional tea, even when the raw amount of kratom plant material looks similar on the label.
The most recent and concerning development involves semi-synthetic products containing 7-hydroxymitragynine (7-OH) or mitragynine pseudoindoxyl (MP). These compounds are derived from mitragynine in the lab and are highly potent opioid receptor agonists that are either undetectable or not present in fresh kratom leaves.7PubMed Central. De facto opioids: Characterization of novel 7-hydroxymitragynine and mitragynine pseudoindoxyl product marketing Researchers who surveyed the online market identified over 300 of these products, most formulated as chewable or sublingual tablets, shots, or gummies.7PubMed Central. De facto opioids: Characterization of novel 7-hydroxymitragynine and mitragynine pseudoindoxyl product marketing These products appeared on vendor websites around 2024 and expanded rapidly, eventually spanning gummies, tablets, syrups, nasal sprays, and other formats.8PubMed Central. From kratom to 7-hydroxymitragynine: evolution of a natural remedy into a public-health threat
This matters because the risk profile of a semi-synthetic 7-OH gummy is fundamentally different from that of a cup of traditional kratom tea. The FDA has recommended scheduling 7-hydroxymitragynine as a controlled substance due to its high potency, ease of access, and addiction risk.9PubMed. Quantitative analysis of 7-hydroxymitragynine in commercial kratom products and its stability under chemical and physiological conditions
Adulteration and What You Might Not Know Is in the Product
One of the least-discussed risks of kratom products is that what is on the label may not match what is in the package. Researchers have found that some commercial kratom products contain concentrations of 7-hydroxymitragynine far higher than what occurs naturally in raw leaves, suggesting intentional spiking or enrichment.10PubMed Central. Suspected Adulteration of Commercial Kratom Products with 7-Hydroxymitragynine For a consumer who thinks they are buying plain kratom powder, this amounts to unknowingly taking a much more potent opioid-like substance.
Beyond alkaloid tampering, kratom products have tested positive for harmful contaminants. An assessment of published analyses found that some products contain excessive concentrations of lead and arsenic, with non-extract forms like powders, capsules, and tablets tending to carry greater levels of heavy metals than extract products.11PubMed. Elemental impurities (heavy metals) in kratom products: an assessment of published individual product analyses Daily use of contaminated products can push exposure past regulatory safety thresholds. A separate study of kratom products sold in Virginia found unsafe levels of manganese in multiple samples, all produced by the same manufacturer. Chronic manganese overexposure can lead to a neurodegenerative condition with symptoms resembling Parkinson’s disease.12Forensic Chemistry. Analysis of heavy metals content in commercially available kratom products in Richmond, Virginia
Microbial contamination is another documented problem. During a multistate Salmonella outbreak in 2017–2018 linked to kratom, the FDA tested 66 kratom samples and found Salmonella in half of them, with some samples harboring more than one strain.13PubMed Central. A Multiple-Serotype Outbreak of Salmonella Infections Linked to Kratom, United States, 2017–2018 A broader FDA investigation found a 55 percent positivity rate among 76 product samples and wide genetic diversity among the Salmonella strains, suggesting that the contamination was not a single-source event but was spread across multiple growing, harvesting, and packaging sites.14Journal of Food Protection. Multistate Outbreak Investigation of Salmonella Infections Linked to Kratom: A Focus on Traceback, Laboratory, and Regulatory Activities The fact that kratom is typically consumed without cooking or other decontamination steps makes bacterial contamination a particularly practical concern.
Liver Injury, Toxicity, and Overdose
Kratom-associated liver injury, while not common, has been documented with enough consistency to warrant attention. A case series from the U.S. Drug Induced Liver Injury Network described 11 patients who developed symptomatic liver injury after kratom use. All became jaundiced, eight required hospitalization, and three developed an elevated clotting measure indicating significant liver dysfunction. No one died, and most recovered within six months, but the injuries were serious enough to require clinical management.15PubMed Central. Liver Injury Associated with Kratom, A Popular Opioid-Like Product: Experience from the U.S. Drug Induced liver Injury Network
The broader range of reported adverse effects from kratom includes problems affecting the lungs, heart, brain, kidneys, and gastrointestinal tract, along with seizures, loss of consciousness, and altered mental state.16PubMed Central. The acute adverse health effects of kratom: an evaluation of case reports In more severe situations, kratom can produce an opioid-like toxicity pattern with respiratory depression that sometimes responds to naloxone, the standard opioid overdose reversal agent. However, the response to naloxone is variable and sometimes delayed or incomplete, which creates challenges for emergency treatment.17PubMed Central. Kratom Toxicity: Pharmacologic Mechanisms, Clinical Risks, and Management Considerations
Kratom-associated deaths almost always involve other substances. A review of coroner reports found that all individuals with mitragynine in their toxicology also tested positive for at least one other substance, with fentanyl present in three out of four cases.18PubMed Central. Presence of kratom in opioid overdose deaths: findings from coroner postmortem toxicological report A separate case report described a fatality attributed to hydromorphone toxicity with mitragynine listed as a contributing factor, alongside elevated markers of kidney impairment.19PubMed. A case of fatal overdose involving both hydromorphone and kratom Teasing apart kratom’s independent contribution to these deaths is difficult precisely because poly-substance use is so common among the people who die.
Drug Interactions Worth Knowing About
If you take other medications, kratom’s effect on drug-metabolizing enzymes is one of its less visible but more dangerous properties. Lab studies have shown that mitragynine strongly inhibits a liver enzyme called CYP2D6, which is responsible for breaking down many common medications including certain antidepressants, beta-blockers, and pain medications.20PubMed Central. Exploration of cytochrome P450 inhibition mediated drug-drug interaction potential of kratom alkaloids When that enzyme is blocked, levels of those medications can build up in your blood to a degree the prescribing doctor never intended.
A clinical study in 12 healthy adults tested what happens when a low dose of kratom tea (2 grams) is taken alongside probe drugs for two key enzyme systems. Kratom had no measurable effect on CYP2D6 activity at that dose, but it produced a modest increase in blood levels of midazolam, a drug metabolized by the CYP3A enzyme family. The researchers concluded that kratom primarily inhibited intestinal CYP3A and warned that co-consuming kratom with drugs extensively metabolized by that enzyme system could precipitate serious interactions.21PubMed Central. Clinical Assessment of the Drug Interaction Potential of the Psychotropic Natural Product Kratom The discrepancy between the lab findings (strong CYP2D6 inhibition) and the clinical findings (no effect at a 2-gram dose) likely reflects the low dose tested. People who use higher or more concentrated doses could face a different interaction profile.
Dependence and Withdrawal
Regular kratom use can produce physical dependence, and the evidence here is fairly consistent. A study of long-term users (more than six months of regular use) found that over half developed severe dependence, while about 45 percent showed moderate dependence. Physical withdrawal symptoms included muscle spasms and pain, difficulty sleeping, watery eyes, hot flashes, fever, decreased appetite, and diarrhea. Psychological symptoms included restlessness, tension, anger, sadness, and nervousness.22PubMed. Kratom (Mitragyna speciosa) dependence, withdrawal symptoms and craving in regular users
Regular use also builds tolerance and cross-tolerance with morphine, meaning that someone using kratom heavily may find that traditional opioid medications become less effective.23PubMed. Kratom Dependence and Treatment Options: A Comprehensive Review of the Literature More recent research reinforces that while some people use kratom without developing problems, the likelihood of physical dependence and meeting criteria for a use disorder increases with the frequency of dosing.24PubMed Central. Kratom addiction per DSM-5 SUD criteria, and kratom physical dependence: Insights from dosing amount versus frequency Occasional or low-frequency users appear to face substantially less risk than daily users.
Why People Use Kratom and What Surveys Show
Understanding who uses kratom and why helps explain its appeal despite the risks. A large survey of nearly 2,800 kratom users found that the typical user was around 40 years old, predominantly white, and more likely female. The most commonly reported reasons for use were pain (91 percent), anxiety (67 percent), and depression (65 percent), and users gave kratom high effectiveness ratings for those purposes. About 41 percent said they used kratom specifically to reduce or stop prescription or illicit opioid use, with many crediting it for reduced withdrawal and craving.25PubMed Central. Kratom (Mitragyna speciosa): User demographics, use patterns, and implications for the opioid epidemic
A separate cross-sectional study echoed these patterns, finding that kratom was primarily used to self-treat pain (73 percent) and to manage emotional or mental health conditions (about 42 percent), generally without clinical supervision. Among those with a substance use disorder history, nearly 95 percent reported using kratom after discontinuing illicit or prescription drugs.26American Journal of Drug and Alcohol Abuse. Exploring the self-reported motivations of kratom (Mitragyna speciosa Korth.) use: a cross-sectional investigation An ecological momentary assessment study found that participants broadly rated kratom as safer than other substances and highly effective at improving quality of life, boosting energy, replacing opioids or alcohol, and relieving withdrawal. About 28 percent reported using it as a long-term opioid substitute.27JAMA Network Open. Ecological Momentary Assessment of Self-Reported Kratom Use, Effects, and Motivations Among US Adults
These surveys reveal a complicated picture. Many kratom users are self-medicating for real conditions, and a significant portion see it as a harm-reduction tool for opioid dependence. But the same self-directed use pattern means most people are navigating dosing, product quality, and interaction risks without medical guidance.
Kratom During Pregnancy
One area where the evidence is thin but the stakes are high involves kratom use during pregnancy. A systematic review of maternal kratom exposure found that withdrawal symptoms were described in both mothers and newborns in every case examined, and both required pharmacological treatment.28PubMed Central. Outcomes of mothers and newborns to prenatal exposure to kratom: a systematic review Individual case reports have documented neonatal abstinence syndrome in infants born to mothers who drank kratom tea daily, with the newborns requiring opioid treatment for withdrawal.29Pediatrics. Neonatal Abstinence Syndrome Due to Maternal Kratom Use30PubMed Central. Natural drugs, not so natural effects: Neonatal abstinence syndrome secondary to ‘kratom’
The evidence base is small, consisting mostly of individual case reports rather than large studies, so it is difficult to say how common neonatal withdrawal is or whether lower levels of kratom exposure carry the same risk. But the cases that do exist are consistent enough to suggest that daily kratom use during pregnancy can cause the same kind of withdrawal syndrome in newborns that prescription opioids do.
How Product Form Shapes Risk
The safety picture for kratom is not a single story. It is several overlapping stories that depend heavily on what form you are using. A person chewing fresh leaves in a traditional setting is getting a limited, self-regulating dose of mitragynine along with the full matrix of other plant compounds. A person swallowing capsules of dried powder is getting a somewhat higher and more consistent alkaloid dose. Someone drinking a concentrated extract shot may be getting double the alkaloid exposure per dose compared to traditional tea. And someone consuming a semi-synthetic 7-OH gummy is using what researchers have described as a de facto opioid that does not naturally exist in the kratom leaf at meaningful concentrations.7PubMed Central. De facto opioids: Characterization of novel 7-hydroxymitragynine and mitragynine pseudoindoxyl product marketing
Layered on top of these inherent differences are the contamination variables: heavy metals from soil uptake and processing, bacterial pathogens from unregulated harvesting and packaging, and undisclosed alkaloid spiking that can make a supposedly mild product behave like a potent one. Without standardized manufacturing, third-party testing requirements, or labeling regulations in most jurisdictions, the consumer bears an unusual amount of the burden for figuring out what they are actually ingesting. If you use kratom in any form, knowing which product category you are dealing with is the single most useful piece of safety information you can have.