Kratom: The Opioid Supplement Hiding in Plain Sight

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Kratom (Mitragyna speciosa) is a Southeast Asian plant whose ground leaves are sold in the United States as a "botanical supplement." You will find it in capsules, powders, and shots at gas stations, convenience stores, smoke shops, and online. The marketing pitches it for energy, mood, and opioid withdrawal. What is usually missing from the label: kratom's two main alkaloids, mitragynine and 7-hydroxymitragynine, act on the same brain receptors as opioid drugs.

The Pharmacology

7-hydroxymitragynine (7-HMG) binds mu-opioid receptors with greater affinity than morphine in laboratory studies, and rats will self-administer it like an opioid. The effects you feel are dose-dependent in the same pattern as a classic opioid: pain relief at low doses, euphoria and sedation at higher doses, and breathing suppression at toxic doses. The DEA proposed Schedule I status for mitragynine and 7-hydroxymitragynine in 2016 and withdrew that proposal after public comment. The withdrawal was not a finding that the alkaloids are safe.

Concentrated 7-OH, 2026

On 26 August 2026 the DEA temporarily placed mitragynine pseudoindoxyl (MGPI) and two synthetic 7-hydroxymitragynine derivatives, MGM-15 and MGM-16, in Schedule I. The 14 October 2026 notice cites that order as 91 FR 54948 and says it stays in effect until 26 August 2028, or until a replacement order is published. The FDA describes the same 26 August action (Hiding in Plain Sight: 7-OH Products).

On 14 October 2026 the DEA published a notice of intent to issue a further temporary Schedule I order for 7-hydroxymitragynine and MGPI (91 FR 65370; Federal Register, 14 October 2026). It follows an HHS letter dated 8 October 2026, which HHS announced on 9 October (HHS, 9 October 2026). The proposal covers either substance, or the two combined, when the amount is above a threshold: more than 1 mg per gram in a solid, or more than 1 mg per millilitre in a liquid, or when the mass of mitragynine divided by the mass of 7-OH, of MGPI, or of both is less than 100. The notice says that line is meant to reach concentrated or enhanced products and not natural botanical kratom, in which 7-OH is a minor or trace alkaloid (under 2 percent of total alkaloids, or a trace). The temporary order will not be issued before 13 November 2026. Neither HHS nor the DEA has found amounts below the threshold to be safe.

HHS, describing FDA’s scientific review, says preclinical studies find 7-OH about two to nine times as potent as morphine, depending on the study. The Federal Register notice says 7-OH has opioid activity comparable to morphine, including tolerance, dependence, and respiratory depression, and that preclinical data show MGPI produces an analgesic effect more potent than morphine. This page stays at Tier 4. A plain-leaf exclusion is not a reason to treat a concentrated 7-OH product as a supplement.

Dependence and Withdrawal

Physical dependence builds with regular use, often within a few weeks. Withdrawal — documented in hundreds of case reports and multiple observational studies — includes muscle aches, insomnia, anxiety, irritability, sweating, nausea, and cravings. The pattern looks like opioid withdrawal, though usually milder. The FDA has received thousands of adverse event reports tied to kratom, and the CDC has linked kratom to dozens of overdose deaths, most involving other drugs. Even when kratom alone is hard to isolate as the cause, the signal is real.

Poison Center Trends

U.S. poison centers logged 3,484 kratom-related calls between 2014 and 2019, with the rate climbing each year, according to American Association of Poison Control Centers (AAPCC) data. Reports include seizures, liver injury, and dozens of deaths in older adults whose cases involved drug interactions. Drug-induced liver injury cases tied to kratom have been published in hepatology journals on multiple continents.

Who Uses Kratom

Kratom has a real user community: people managing chronic pain, tapering off prescription opioids, and recreational users. Some users say it helps. For someone already dependent on opioids, kratom may be less harmful than illicit fentanyl. But that is a medical decision — one that belongs in a clinic with a doctor and a withdrawal plan, not in the checkout line at a gas station.

The Regulatory Gap

Because kratom is sold as a supplement rather than a drug, it skips the FDA approval process. Products vary widely in potency, can be contaminated, and have no required dosing standards. The American Kratom Association has lobbied to keep kratom unscheduled. Several states have passed a Kratom Consumer Protection Act that requires labeling and basic purity standards — a small step toward harm reduction, but it does not resolve the bigger safety questions.