Kratom glossary: plant, chemistry, testing and regulation terms explained

Plain-language definitions of the terms that appear on Canadian kratom vendor sites, lab reports, regulatory notices and in the research literature. Entries link to the guide that covers each topic in depth. This is a reference; it does not recommend products or describe how to use them.

Last reviewed: November 9, 2026. Part of the KratomSource knowledge base.

Plant and product

Mitragyna speciosa. The tree whose dried leaf is sold as kratom. A member of the coffee family native to Southeast Asia. See what kratom is and where it comes from.

Kratom, ketum, biak, kakuam, thang, thom. Regional names for the same leaf: kratom (Thai, now the international term), ketum or biak (Malay), and others.

Leaf powder. Dried, de-stemmed, ground leaf. The standard product, usually around 1–2% mitragynine by weight.

Crushed leaf. Dried leaf broken rather than powdered; sold for tea-style preparation. Same material, coarser.

Stem and vein. The by-product of de-veining: the leaf’s midribs and stems, ground. Lower in alkaloids.

Extract. A concentrate made by dissolving alkaloids out of leaf with water, alcohol or other solvents and evaporating. Labelled by ratio (e.g. “15x”, meaning 15 kg of leaf per kg of extract, in principle) or by stated mitragynine percentage. Alkaloid content can be five to fifty times that of leaf. Not scored by KratomSource.

Enhanced leaf. Leaf powder with extract added back to raise potency. Occupies a grey zone between leaf and extract and should be labelled as such.

7-OH products. Tablets, gummies or liquids containing concentrated or synthetic 7-hydroxymitragynine, often at hundreds of times the level found in leaf. A different product category with a different risk profile; see the 7-OH guide.

Strain. A vendor’s product name, such as Maeng Da, Bali or Borneo. Not a botanical variety; see strains and vein colours.

Vein colour (red, green, white, yellow, gold). A label that mainly reflects how the leaf was dried and whether it was fermented, loosely linked to the colour of the fresh leaf’s veins. Not a reliable predictor of alkaloid content.

Bentuangie. A processing designation for deliberately fermented red leaf.

Maeng Da. Thai slang, roughly “pimp grade”; a processor’s premium-grade label, not an origin.

Hulu Kapuas / Kapuas Hulu. The regency in West Kalimantan, Indonesia, that is the centre of world kratom production.

Lot / batch number. The identifier a vendor assigns to a quantity of powder repacked at one time. The only thing that connects a certificate of analysis to a bag.

Chemistry and pharmacology

Alkaloid. A nitrogen-containing plant compound with physiological activity. Kratom leaf contains more than 40. See alkaloids and pharmacology.

Mitragynine. The principal alkaloid, roughly two-thirds of the leaf’s total. A partial agonist at the mu-opioid receptor with additional adrenergic and serotonergic activity.

7-hydroxymitragynine (7-OH). A minor leaf alkaloid, below 0.05% in natural leaf, and the main active metabolite the liver makes from mitragynine. Several times more potent at the opioid receptor than mitragynine. The compound regulators focus on.

Paynantheine, speciogynine, speciociliatine. The next most abundant leaf alkaloids. Their presence in a natural ratio to mitragynine is one way a lab confirms a powder is unadulterated leaf.

Mitragynine pseudoindoxyl. A further metabolite and oxidation product studied for its own opioid activity.

Partial agonist. A compound that activates a receptor but produces a smaller maximum effect than a full agonist such as morphine.

Biased agonism (G-protein bias). The laboratory finding that mitragynine and 7-OH activate the mu-opioid receptor’s G-protein pathway with little beta-arrestin recruitment. The basis of claims about reduced respiratory risk; a signalling observation, not a safety demonstration.

CYP3A4, CYP2D6. Liver enzymes that metabolize mitragynine and many medications. Mitragynine inhibits both in laboratory assays, which is the basis for interaction concerns.

Tolerance, dependence, withdrawal. Tolerance: needing more for the same effect over time. Dependence: the body adapting so that stopping produces withdrawal. Withdrawal: the symptoms on stopping, described for kratom in the research summary.

Kratom use disorder. A pattern of use meeting DSM-5 substance use disorder criteria. Reported by a minority of survey respondents.

Testing

Certificate of analysis (COA). A laboratory’s report of what it measured in a specific sample. See how to read a COA and lab testing explained.

Supplier COA vs retail-lot COA. A test on the bulk lot before export versus a test on the powder the Canadian vendor actually sells after repacking. Only the second describes what a customer receives.

Third-party testing. Testing by a lab independent of the vendor. Stronger when the sample was also bought independently, as in KratomSource’s programme.

ISO/IEC 17025. The international standard for the competence of testing laboratories. Accreditation to it, by a body such as the Standards Council of Canada or CALA, is the usual mark of a credible lab.

HPLC / LC-MS/MS. Liquid chromatography methods used to separate and quantify alkaloids and mycotoxins.

ICP-MS. Inductively coupled plasma mass spectrometry, the standard method for heavy metals.

ppm, ppb, µg/kg, mg/kg. Concentration units. 1 ppm = 1 mg/kg; 1 ppb = 1 µg/kg. Heavy metals are usually reported in ppm, mycotoxins in ppb.

CFU/g. Colony-forming units per gram, the unit for bacterial and fungal counts.

LOD / LOQ. Limit of detection and limit of quantitation: the smallest amount a method can detect or reliably measure. “< LOQ” means below that limit, not zero.

TAMC / TYMC. Total aerobic microbial count and total yeast and mould count.

Aflatoxins, ochratoxin A. Mycotoxins produced by moulds on damp plant material; tested because they survive drying and are toxic at very low levels.

GMP (Good Manufacturing Practice). A quality system for production. The American Kratom Association runs a voluntary GMP qualification for vendors; Health Canada GMP requirements for natural health products do not apply to kratom because it is not an authorized product.

Regulation

Natural health product (NHP). Health Canada’s category for vitamins, herbal remedies and similar products, which require a product licence (NPN) to be sold for consumption. No kratom product holds one. See is kratom legal in Canada.

“Not for human consumption.” The labelling Canadian vendors use to sell kratom as a botanical rather than as an unlicensed health product. The legal basis of the Canadian market and the source of most of its contradictions.

Controlled Drugs and Substances Act (CDSA). Canada’s drug-control statute. Kratom and its alkaloids are not scheduled under it.

Health Canada enforcement. Seizures, advisories and import refusals targeting kratom marketed for consumption. Tracked on our enforcement page.

Kratom Consumer Protection Act (KCPA). US state laws that regulate rather than ban kratom, typically with age limits, labelling and 7-OH caps. No Canadian equivalent exists.

Import alert. An FDA mechanism allowing detention of kratom shipments at the US border without physical examination. Canada has no equivalent standing alert; shipments are handled case by case.

WHO ECDD. The World Health Organization’s Expert Committee on Drug Dependence, which pre-reviewed kratom in 2021 and did not recommend international control.

Indonesian export regulation (2024). Ministry of Trade rules requiring exported kratom to meet contamination standards and restricting product forms. See how kratom is processed.

Buying

Kilo price. The price of 1,000 g of leaf powder, the standard unit for comparing Canadian vendors. Our rankings list it in CAD.

Split kilo. A kilogram made up of several strains at the kilo price.

Interac e-Transfer. The dominant payment method among Canadian vendors because card processors frequently refuse kratom merchants.

Affiliate link / sponsored. A link that pays the referring site a commission. KratomSource marks any such link with rel=”sponsored” and discloses it on the vendor page; see How we test.

Frequently asked questions

What does COA mean on a kratom site?

Certificate of analysis: a laboratory's report of what it measured in a specific sample. It should carry a lab name, lot number, date, methods and actual values.

What does 'not for human consumption' mean on kratom in Canada?

It is the labelling Canadian vendors use to sell kratom as a botanical rather than as an unlicensed natural health product, since Health Canada has not authorized any kratom product for consumption.

What is 7-OH?

7-hydroxymitragynine, a trace leaf alkaloid and the main active metabolite of mitragynine. Concentrated 7-OH products are a separate category from leaf powder.