On August 26 the Drug Enforcement Administration placed three kratom-derived compounds into Schedule I by temporary order, effective the day it published. Two of them, mitragynine pseudoindoxyl and MGM-15, are semisynthetic opioids far more potent than the alkaloid that gives kratom leaf its effect.
Eight weeks later, researchers at the University of Mississippi’s National Center for Natural Products Research posted the results of a shopping trip. They had bought 46 chewable or unit-dose products from online retailers and three gas stations in Mississippi during September. All 46 were labeled as containing cat’s claw, a South American vine with no known opioid activity. None declared any kratom alkaloid.
All 46 contained at least one. Thirty-nine of them, 85 percent, contained mitragynine pseudoindoxyl or MGM-15, two of the three compounds scheduled in August. The third, MGM-16, was not in the laboratory’s analyte panel, so the study says nothing about it either way. Nor is this a measurement of the category: it is what 17 brands shipped to one laboratory in one month.
What those 46 packages show is a gap between two systems. Scheduling attaches to a molecule. Retail distribution attaches to a label. In this sample the two had come apart, and the people who noticed were state poison centers, a state crime lab and a university laboratory.
What the testing found
The products represented 17 brands, often several flavors per brand. Methanol extracts were run by ultra-high-performance liquid chromatography with photodiode array detection, compared against an extract of botanically verified Uncaria tomentosa bark, with mass spectrometry to identify additional compounds. Nine compounds were quantified against authentic reference standards.
Mitragynine turned up in 41 products, 7-hydroxymitragynine in 35, MGM-15 in 24 and mitragynine pseudoindoxyl in 22. Tianeptine, an antidepressant not approved in the United States and itself the subject of a DEA scheduling proposal, was in five products at 27.9 to 40.2 mg per unit. One product also carried yohimbine, melatonin and lidocaine.
Two details matter more than the headline percentages.
The first is dose spread. The 7-OH content ranged from 0.01 to 95.4 mg per unit. Sixteen products held 22.2 mg or more and twelve held 40 mg or more. Within a single five-flavor product line, the amount ranged from 45.2 to 84.2 mg depending on which flavor a customer picked. A consumer choosing between two flavors of the same product was choosing between doses of an opioid, with nothing on either package to say so.
There is a federal yardstick for what those numbers mean, though it measures concentration rather than dose. In the proposal DEA published on October 14, drawn from an HHS analysis, 7-OH and mitragynine pseudoindoxyl fall into Schedule I once either exceeds 1 mg per gram of a solid product, or once mitragynine outweighs them by less than 100 to 1. The point of the line, in DEA’s words, is to separate products “intentionally enhanced or concentrated” from those whose alkaloid mix still resembles the plant. In the leaf, DEA notes, 7-OH is under two percent of total alkaloids or a trace. These are chewable tablets carrying up to 95.4 mg of it.
The second is the negative labeling. Eight products carried claims like “NO KRATOM and No 7-OH” or “NO 7-OH.” All eight contained mitragynine, 7-OH and 3-dehydromitragynine. The claim most likely to reassure a cautious buyer was the one the chemistry contradicted.
As for the cat’s claw itself, the authors report that the labeled ingredient was not detected in 41 of the 46 products. Only five contained Uncaria alkaloids, they write, and each of those also contained kratom-derived compounds, which they say suggests deliberate addition rather than botanical origin. A single Uncaria marker compound turned up in 13 products, but none carried the alkaloid profile of authenticated cat’s claw bark. That inference is about how the compounds got into the products. It is not a finding about why they carry the label they carry, and the paper does not make one.
Why the architecture misses this
Federal control of these compounds runs through the Controlled Substances Act, which schedules substances, not packages. Once mitragynine pseudoindoxyl is in Schedule I, possessing or distributing it is an offense regardless of what the box says. The enforcement problem is not legal authority. It is detection.
A dietary supplement does not undergo pre-market testing for identity in the way a drug does. Nothing routinely checks that the botanical named on a supplement label is the botanical in the capsule, and the compounds at issue here are invisible without chromatography. A package reading cat’s claw, sold beside the register at a gas station, presents no feature that an inspector, a pharmacist or a buyer could use to tell it apart from the authentic article.
That is why the labeling is the operative fact, not an incidental one. The scheduled compounds did not have to be hidden cleverly. They had to be put in a box with a different plant’s name on it.
One thing the record does not support is that scheduling caused the relabeling. Utah’s poison center issued its first alert about adulterated cat’s claw products on July 22, more than a month before the August order took effect, naming the brands Buzzers and Homiez. Whatever is driving the use of this label, it was already underway before the federal action that would have given anyone a reason to evade it.
Who is actually finding these products
Utah’s Department of Health and Human Services announced on October 5 that four deaths in the state had been linked to high-potency illegal compounds in herbal supplements including kratom products and cat’s claw. Its Department of Agriculture and Food identified mitragynine pseudoindoxyl and MGM-15 in products sold online and in smoke shops and gas stations, sold under brands including Buzzers and labeled as cat’s claw or Uncaria tomentosa. Under Utah law only pure leaf kratom may be sold, so these products were already illegal there.
In Tennessee, where kratom is illegal in any form, the Bureau of Investigation warned in September that its crime lab had taken in 18 submissions since July of tablet packs labeled cat’s claw that were laced with kratom. Virginia’s health department issued a notice on September 17. The Washington Poison Center followed on October 7, after a resident there overdosed and was revived with naloxone, and advised the public to discard any cat’s claw product bought from a vape shop, gas station, convenience store or online.
Against that, the federal product-level record reads differently. FDA’s enforcement on this family of compounds, including warning letters, has been directed at products marketed openly as 7-OH. Its public page on the subject, titled Hiding in Plain Sight and current as of October 12, sets out the scheduling actions and the proposed thresholds and does not mention cat’s claw or Uncaria at any point. A search of FDA’s public materials on October 26 turned up no warning letter, import alert or consumer advisory naming cat’s-claw-labeled products. That is a statement about what is publicly visible, not about what may be underway.
One institutional fact is worth stating plainly. The laboratory that produced these results is supported by FDA, through a long-standing cooperative agreement with the Center for Food Safety and Applied Nutrition for authenticating botanical ingredients. The agency funds the capability that found this. What follows from a finding four days old is a separate question, and nothing in the record says FDA saw these results before the preprint went up.
What this evidence can and cannot carry
The paper is a preprint, posted October 22 and not peer reviewed. Its authors are direct about the limits: 46 products from 17 brands at a single time point, no clinical outcome data, batch variability unassessed, and a targeted analyte panel that did not include MGM-16, the third compound scheduled in August. They state that they did not link any product to a specific case.
So this is not a measurement of the cat’s claw category. It is a sample of 46 products bought in one month through channels the researchers chose, and it says nothing about cat’s claw supplements sold through other retailers. Nor does it establish that any of these specific products caused any of the deaths reported in Utah or elsewhere. The authors describe their findings as consistent with the toxicity that Utah and Tennessee officials have attributed to similarly branded products, which is the correct strength of claim and worth preserving.
What the sample does establish, within itself, is that the label carried no information about the contents, including for the products whose labels made an explicit negative claim. That holds regardless of how representative the sample is, because it is a statement about those 46 packages.
What to watch
Whether FDA uses its product-level tools here is the first test. A warning letter naming these brands, an import alert, or a seizure would show the federal response extending from the molecule to the package. None has appeared so far.
The second is the threshold proposal DEA published on October 14, which would control 7-OH and mitragynine pseudoindoxyl above a concentration or below a mitragynine ratio. A threshold makes legality a laboratory question. On the evidence here, the laboratories answering it sit at universities and state crime labs, not at the point of sale.
The third is replication. A single preprint from one laboratory, however carefully done, is one sample. Peer review, a second laboratory, or testing of products bought in other states would show whether this is a regional pattern or a national one.
The last is the gap between states. These products were already illegal in Utah and in Tennessee before any of this. The same online retailers ship to states where they are a serious crime and to states where they are a contested supplement, which is a distribution question rather than a scheduling one.
Scheduling a molecule settles what is illegal. It does not settle who is going to open the box.