Classification
Botanical mixture with partial agonist activity at the μ-opioid receptor
Journal of the American Chemical Society, 2016National Institute on Drug Abuse (NIDA), 2025Laden…
Botanical · opioid-active alkaloids · heterogeneous products
Mitragyna speciosa
Kratom refers to preparations from Mitragyna speciosa. The alkaloids mitragynine and 7-hydroxymitragynine contribute to opioid activity; both activating and sedating effects are described depending on product and exposure. Leaf, tea, extracts, and enriched 7-OH products are not interchangeable.
Botanical mixture with partial agonist activity at the μ-opioid receptor
Journal of the American Chemical Society, 2016National Institute on Drug Abuse (NIDA), 2025Mitragynine; 7-hydroxymitragynine usually occurs at low levels in leaf but can be highly enriched in novel products
ACS Central Science, 2019Journal of AOAC International, 2026often around 15–45 minutes; dependent on product, food, and individual factors
Pharmaceutics, 2022Drug and Alcohol Dependence, 2017often several hours; not the same as the substantially longer elimination phase
Pharmaceutics, 2022Drug and Alcohol Dependence, 2017moderate and heterogeneous: small human studies, observational data, case reports, and preclinical research
WHO Expert Committee on Drug Dependence, 2021Bundesinstitut für Risikobewertung (BfR), 2025no blanket BtMG classification; marketing can still be unlawful under medicinal-product or food law
Bundesinstitut für Risikobewertung (BfR), 2025Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM), 2025Bundesministerium der Justiz / Bundesamt für Justiz, 2026Product forms
Product form is safety-critical information. Potency, predictability, and the applicability of research evidence differ substantially.
A water-based leaf preparation with a variable alkaloid profile. Human tea studies apply only to the analysed study product.
Preparation and plant material alter the actual exposure.
Drug and Alcohol Dependence, 2017Clinical Pharmacology & Therapeutics, 2023Dried plant material; batches and alkaloid concentrations still differ.
Gram amounts describe mass, not a reliable active-alkaloid concentration.
Drug and Alcohol Dependence, 2017Phytochemistry, 2026May contain leaf powder or concentrated material. The format alone does not establish strength.
Labelling, fill weight, and alkaloid profile must be assessed separately.
Bundesinstitut für Risikobewertung (BfR), 2025Phytochemistry, 2026Concentrated products for which leaf gram amounts do not transfer.
Ratios such as “10×” are not a reliable potency measure without validated analysis.
Bundesinstitut für Risikobewertung (BfR), 2025Phytochemistry, 2026Concentrated products with a declared mitragynine content. Standardizing one alkaloid does not remove all uncertainty.
Other alkaloids, analytical quality, bioavailability, and conversion to 7-OH remain relevant.
Molecules, 2024Phytochemistry, 2026Tablets, gummies, shots, or mixtures with 7-hydroxymitragynine levels that do not resemble ordinary leaf.
Greater opioid potency, rapid tolerance development, and labelling uncertainty increase risk.
ACS Central Science, 2019Journal of AOAC International, 2026Products without credible ingredient and concentration data cannot be meaningfully classified.
Unexpected substances, contaminants, or materially higher concentrations are possible.
Bundesinstitut für Risikobewertung (BfR), 2025National Institute on Drug Abuse (NIDA), 2025Effects
Kratom is not a single compound. Subjective effects and adverse effects depend on alkaloid profile, product form, exposure, tolerance, context, and co-use. A simple “stimulating at low amounts, sedating at high amounts” rule is too crude.
Surveys describe alertness, energy, talkativeness, or feeling more functional. These observations do not establish a classic stimulant mechanism or a reliable product class.
Drug and Alcohol Dependence, 2017National Institute on Drug Abuse (NIDA), 2025Relaxation, warmth, reduced pain perception, tiredness, and an opioid-like body sensation are reported. Greater sedation raises risk, especially with other depressants.
Drug and Alcohol Dependence, 2017Journal of the American Chemical Society, 2016Bundesinstitut für Risikobewertung (BfR), 2025Nausea, vomiting, constipation, dizziness, drowsiness, sweating, itching, agitation, or palpitations are described. Product heterogeneity prevents reliable prediction of frequency and severity.
Bundesinstitut für Risikobewertung (BfR), 2025National Center for Complementary and Integrative Health, 2025WHO Expert Committee on Drug Dependence, 2021Reported severe presentations include seizures, altered consciousness, profound sedation, breathing problems, and liver injury. Many severe cases involve co-use or uncertain products, which complicates causality without removing the safety signal.
WHO Expert Committee on Drug Dependence, 2021Bundesinstitut für Risikobewertung (BfR), 2025Drug and Alcohol Dependence, 2021These labels are not validated pharmacological classes. Colour, processing, batch, blends, and marketing can overlap. A strain name therefore cannot reliably predict alkaloid composition or effects.
Phytochemistry, 2026Bundesinstitut für Risikobewertung (BfR), 2025Amounts
There is no product-independent safe kratom dose. Leaf mass, extract mass, and isolated alkaloid content are different quantities. The figures below document research exposure and are not recommendations.
Small controlled studies examined analysed dried-leaf material from 0.5 to 4 g, or a single 2 g exposure. These figures apply only to the studied batches, populations, and protocols; they do not define a safe or equivalent real-world dose.
Pharmaceutics, 2022Molecules, 2024Gram amounts are only narrowly interpretable across comparable leaf products. Tea and swallowed leaf can produce different exposures from the same starting mass.
Pharmaceutics, 2022Clinical Pharmacology & Therapeutics, 2023Leaf gram scales must not be carried over to extracts. Independently verified alkaloid content per serving and package would be more informative, though it still does not fully capture other alkaloids or bioavailability.
Phytochemistry, 2026Bundesinstitut für Risikobewertung (BfR), 2025Enriched 7-OH products can contain concentrations unlike the chemical profile of ordinary leaf. They require their own risk assessment and must not be treated as “ordinary kratom” or converted using leaf equivalents.
Journal of AOAC International, 2026ACS Central Science, 2019No extract equivalence: A break in use, illness, new medication, or product change can alter a familiar response. Tolerance does not reliably protect against breathing risk, interactions, or product errors.
Time course
Subjective effects end well before complete elimination. Timing estimates concern oral leaf products and do not transfer to extracts or enriched 7-OH.
often about 15–45 min
Food, gastric emptying, product, and formulation can shift onset.
about 30–90 min
Early redosing can underestimate the exposure that appears later.
often around 1–2 h
Human PK data show alkaloid-dependent plasma peaks roughly between 1 and 4.5 hours; plasma peak and subjective peak are not identical.
often about 3–6 h
Sedation, nausea, or impairment may persist longer.
variable, sometimes into the next day
Especially with frequent use, high concentrations, co-use, or sleep loss.
In a study of six healthy participants, terminal half-lives for different alkaloids were roughly 12 to 45 hours. A multiple-dose study also found complex, alkaloid-dependent profiles. This does not mean the main effects remain noticeable for that long, but it helps explain accumulation with frequent use.
Pharmaceutics, 2022Molecules, 2024Pharmacology
The effect profile arises from multiple alkaloids and metabolites. Cellular and animal findings can explain possible mechanisms but do not replace clinical efficacy or safety evidence.
Mitragynine and especially 7-hydroxymitragynine show opioid-receptor activity. Preclinical studies describe signalling that differs from classic full agonists; this must not be interpreted as absence of breathing or dependence risk.
Journal of the American Chemical Society, 2016ACS Central Science, 2019WHO Expert Committee on Drug Dependence, 2021Preclinical work and a small human study support CYP3A-mediated conversion of mitragynine to 7-OH as a contributor to effects. The extent can vary with product, metabolism, and interactions.
ACS Central Science, 2019ACS Pharmacology & Translational Science, 2024Animal studies showed alpha-2-like functional effects, while newer receptor studies do not support a simple alpha-2 agonist explanation and report antagonist or alpha-1A partial-agonist activity. “Alpha-2 agonist” is therefore not an established clinical shorthand.
European Journal of Pharmacology, 2024ACS Chemical Neuroscience, 2025Kratom alkaloids use several metabolic pathways. Small human studies show a clinical interaction signal at intestinal CYP3A; laboratory findings alone cannot predict every medication interaction.
Clinical Pharmacology & Therapeutics, 2023ACS Pharmacology & Translational Science, 2024Mechanisms depend on product and alkaloid composition. Findings for an isolated molecule must not be transferred uncritically to leaf, extracts, or mixed products.
Interactions
Most combinations lack controlled human studies. The classification separates direct human findings, case-report signals, and pharmacologically grounded caution. “No data” does not mean “no interaction.”
Additive sedation, loss of consciousness, vomiting/aspiration, and breathing problems are plausible; severe kratom cases are often confounded by co-use. Treat the combination as particularly risky.
Warning signs: Cannot be woken, slow or irregular breathing, blue lips, gurgling sounds.
WHO Expert Committee on Drug Dependence, 2021Bundesinstitut für Risikobewertung (BfR), 2025National Institute on Drug Abuse (NIDA), 2025In twelve healthy participants, a low kratom-tea exposure moderately increased midazolam exposure, consistent with intestinal CYP3A inhibition. The result cannot clear other exposures, extracts, or narrow-therapeutic-index medicines.
Warning signs: Unexpectedly strong or prolonged medicine effects, drowsiness, circulatory symptoms.
Clinical Pharmacology & Therapeutics, 2023Evidence is insufficient for a blanket statement about SSRIs, SNRIs, or tricyclic antidepressants. Enzyme inhibition, additive adverse effects, and case reports support caution; uncertainty is especially high with MAO inhibitors and warrants professional review.
Warning signs: Severe agitation, confusion, fever, muscle rigidity or jerking, pronounced diarrhoea.
Clinical Pharmacology & Therapeutics, 2023WHO Expert Committee on Drug Dependence, 2021Heart rate, blood pressure, agitation, sleep deprivation, and overheating may compound. Kratom can subjectively mask overstimulation without removing physiological strain.
Warning signs: Chest pain, very rapid or irregular pulse, overheating, severe agitation.
Bundesinstitut für Risikobewertung (BfR), 2025National Center for Complementary and Integrative Health, 2025Drowsiness, dizziness, vomiting, disorientation, and accident risk may increase. Sedating antihistamines are not a reliable self-treatment for kratom adverse effects.
Warning signs: Collapse, repeated vomiting, inability to walk or communicate safely.
Bundesinstitut für Risikobewertung (BfR), 2025National Institute on Drug Abuse (NIDA), 2025Kratom has been associated with clinically significant, sometimes cholestatic liver injury. Additive risk from combinations is unquantified; medical review is especially important.
Warning signs: Yellow skin or eyes, dark urine, pale stool, severe itching, right upper abdominal pain.
Drug and Alcohol Dependence, 2021Journal of Addiction Medicine, 2026Risks
Risks range from common gastrointestinal and circulatory symptoms to dependence, withdrawal, and rare severe presentations. Product uncertainty and co-use make individual prediction difficult.
Vomiting is commonly reported. With profound sedation, vomit can be aspirated; a person with impaired consciousness must not be left alone.
Bundesinstitut für Risikobewertung (BfR), 2025WHO Expert Committee on Drug Dependence, 2021Kratom is not equivalent to classic heroin or fentanyl, yet opioid-type emergency signs can occur—especially with 7-OH products, high concentrations, or additional depressants.
WHO Expert Committee on Drug Dependence, 2021Journal of Medical Toxicology, 2019Journal of AOAC International, 2026Seizures, tachycardia, blood-pressure changes, and rhythm abnormalities have been reported. Causality and frequency are uncertain because of co-use and case-report bias.
Bundesinstitut für Risikobewertung (BfR), 2025WHO Expert Committee on Drug Dependence, 2021Regular use can accompany constipation, sleep disruption, fluctuating drive, and emotional blunting. Cause, context, and withdrawal effects can overlap.
Drug and Alcohol Dependence, 2014WHO Expert Committee on Drug Dependence, 2021Rare but clinically significant liver injury is documented, often with jaundice and a cholestatic pattern. Individual prediction is currently not possible.
Drug and Alcohol Dependence, 2021Journal of Addiction Medicine, 2026Changing alkaloid concentrations, undeclared enrichment, and contaminants make stable exposure difficult. This is especially relevant to online extracts and mixed products.
Phytochemistry, 2026Journal of AOAC International, 2026Bundesinstitut für Risikobewertung (BfR), 2025Regular use can lead to reduced effect, more frequent redosing, escalation, and use to relieve withdrawal. This is not limited to isolated 7-OH.
Drug and Alcohol Dependence, 2014Journal of Psychoactive Drugs, 2019WHO Expert Committee on Drug Dependence, 2021Withdrawal can include opioid-like physical symptoms and psychological symptoms. Intensity and duration vary with frequency, exposure, product, duration of use, and comorbidity; it is not established as “always mild.”
Journal of Psychoactive Drugs, 2019Drug and Alcohol Dependence, 2014WHO Expert Committee on Drug Dependence, 2021Seek help early with daily use, marked loss of control, severe withdrawal, pregnancy, major physical or mental illness, co-use, or suicidal thoughts. Abruptly stopping alone is not the safest option in every situation.
Harm reduction
Harm reduction does not make kratom safe. The largest levers are product clarity, avoiding depressant combinations, allowing time rather than redosing quickly, and responding early to dependence signs.
Treat leaf/powder, tea, extracts, and 7-OH products separately. Do not transfer leaf gram values to extracts; assume high uncertainty when labelling is unclear.
Journal of AOAC International, 2026Bundesinstitut für Risikobewertung (BfR), 2025Do not combine with opioids, benzodiazepines/Z-drugs, alcohol, GHB/GBL, gabapentinoids, or other strongly sedating agents. Staggered use can still overlap because elimination is prolonged.
WHO Expert Committee on Drug Dependence, 2021Pharmaceutics, 2022Onset and plasma peaks can be delayed. Early redosing increases the risk of unexpectedly high total exposure.
Pharmaceutics, 2022Molecules, 2024With an unknown product, new batch, after a break, during illness, or with additional medication, a sober person should be reachable and know emergency signs.
Bundesinstitut für Risikobewertung (BfR), 2025National Institute on Drug Abuse (NIDA), 2025Drowsiness, dizziness, nausea, and after-effects can impair reaction and judgement. Do not drive or operate machinery.
Bundesinstitut für Risikobewertung (BfR), 2025National Center for Complementary and Integrative Health, 2025Record product, timing, frequency, adverse effects, and withdrawal symptoms. Increasing frequency or using merely to feel “normal” are early warning signs.
Drug and Alcohol Dependence, 2014Journal of Psychoactive Drugs, 2019With jaundice, dark urine, pale stool, severe itching, or persistent right upper abdominal pain, stop kratom and seek prompt medical assessment.
Drug and Alcohol Dependence, 2021Journal of Addiction Medicine, 2026Daily use is not a moral failure. It is a practical signal to review tolerance, withdrawal, product strength, and co-use in a structured way.
Synapedia offers orientation but does not replace medical diagnosis or treatment.
Call 112 immediately, check breathing, do not leave the person alone, and follow dispatcher instructions. If breathing, use the recovery position; if not breathing normally, start resuscitation as directed.
For an opioid-type emergency, naloxone may be used if available and the responder knows how. Case reports describe improvement after naloxone, but response in kratom toxicity is not guaranteed. Naloxone never replaces calling 112 or ventilation/resuscitation and cannot reverse every co-ingestant hazard.
National Capital Poison Center, 2025Journal of Medical Toxicology, 2019Cureus, 2023Synapedia community
These observations come only from actually approved Synapedia reports and discussions. They are not medical evidence.
3
assigned reports
2
textually relevant to kratom
1
misassigned report excluded
0
approved threads
The sample is too small for percentages or frequency claims.
Kratom should not be described categorically as “illegal under the BtMG.” In the schedules reviewed on 30 July 2026, Kratom, mitragynine, and 7-hydroxymitragynine were not listed by name in BtMG Schedules I–III.
This does not mean every kratom product can be lawfully marketed. BfR and BfArM state that classification is not finally settled: kratom preparations are not authorised medicines; as foods, they may be unauthorised novel foods or unsafe foods. Competent state authorities assess specific products and intended uses. Concentrated, enriched, or differently marketed products may require a different assessment.
Sources last checked: 30 July 2026. This is not legal advice; check the current product-specific position before purchase, import, possession, or sale.
Bundesinstitut für Risikobewertung (BfR), 2025Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM), 2025Bundesministerium der Justiz / Bundesamt für Justiz, 2026European Commission, 2026These questions mark limits of current evidence, not an automatic absence of risk.
Trust
Each source is tied to a claim domain. “Reviewed” means editorial source review—not individual medical clearance.
Bundesinstitut für Risikobewertung (BfR) · 2025
Contributes: German risk communication on products, adverse effects, and classification.
Limit: Regulatory assessment; emphasises limited evidence and is not a product-specific legal ruling.
Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM) · 2025
Contributes: Current German authority statement on lack of medicinal-product authorisation.
Limit: Not a final decision on every specific product.
Contributes: Official current substance schedules; no named Kratom/mitragynine entry found on the review date.
Limit: Absence of a named entry does not by itself determine marketing or product law.
Contributes: EU framework for checking novel-food status.
Limit: The catalogue is non-binding; authorities decide individual cases.
WHO Expert Committee on Drug Dependence · 2021
Contributes: Broad international review of pharmacology, toxicity, dependence, and case reports.
Limit: Many severe cases are confounded by co-use and heterogeneous products.
Contributes: Research-based overview of effects, products, dependence, and uncertainties.
Limit: Secondary government overview, not an individual primary study.
Contributes: Government overview of benefit claims, adverse effects, and research limits.
Limit: Secondary source; not product-specific.
Drug and Alcohol Dependence · 2017
Contributes: Large online survey of use patterns and self-reported effects.
Limit: Self-selection, self-report, no product analysis, and no causal inference.
Pharmaceutics · 2022
Contributes: Analysed 2 g leaf product; human PK for multiple alkaloids.
Limit: Only six healthy participants and one low exposure; not generalisable to extracts.
Molecules · 2024
Contributes: Controlled human PK using 0.5–4 g of analysed dried leaf.
Limit: Small healthy sample, specific study product, and disclosed industry conflicts.
Clinical Pharmacology & Therapeutics · 2023
Contributes: Controlled study in twelve people; modest midazolam/intestinal-CYP3A signal.
Limit: Low tea exposure and small healthy sample; not generalisable to high exposure, extracts, or every medicine.
ACS Pharmacology & Translational Science · 2024
Contributes: Small clinical study supports CYP3A-mediated formation of 7-OH in humans.
Limit: Specific tea/inhibitor protocol; not a complete explanation of subjective effects.
Journal of the American Chemical Society · 2016
Contributes: Receptor and signalling data for Mitragyna alkaloids.
Limit: Predominantly preclinical; cellular signalling is not a clinical safety guarantee.
ACS Central Science · 2019
Contributes: Preclinical data on 7-OH formation, potency, and opioid activity.
Limit: Animal, cellular, and ex-vivo evidence; not a direct clinical dosing basis.
European Journal of Pharmacology · 2024
Contributes: In-vitro and animal data on adrenergic hypotheses.
Limit: No clinical confirmation; functional animal findings without simple in-vitro receptor activation.
Contributes: Newer in-vitro findings challenge a simple alpha-2 agonist classification.
Limit: Receptor assay without clinical exposure or outcome assessment.
Drug and Alcohol Dependence · 2014
Contributes: Observational data from 293 regular users on dependence and withdrawal.
Limit: Regional, non-randomised self-report sample in a traditional-use context.
Contributes: Systematic review and case series on clinical withdrawal presentations.
Limit: Small heterogeneous case literature with publication bias; no standard withdrawal trajectory.
Drug and Alcohol Dependence · 2021
Contributes: Well-characterised cases of clinically significant kratom-associated liver injury.
Limit: Case series without incidence estimate; product composition not always fully known.
Contributes: Current systematic synthesis of published liver-injury cases.
Limit: Case-report literature cannot quantify frequency or individual risk.
Phytochemistry · 2026
Contributes: Current analytical evidence on variability across commercial products.
Limit: Product sample does not represent the entire rapidly changing market.
Journal of AOAC International · 2026
Contributes: Analytical study identifies highly enriched 7-OH products with non-leaf-like profiles.
Limit: Market sample; chemical analysis does not directly quantify clinical event rates.
Contributes: Toxicology emergency guidance, including naloxone when a person is not breathing.
Limit: US emergency context; does not replace German emergency services or clinical evidence.
Contributes: Case report of clinical improvement after naloxone.
Limit: Single case; does not establish typical effectiveness or product safety.
Contributes: Additional clinical case report of response to naloxone.
Limit: Single case with limited generalisability; mixed products may respond differently.