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Kratom619
🧪 The chemistry, in plain English

Rhynchophylline, Mitraphylline & Corynoxine B

Every brand in the new cat's-claw wave says “an indole alkaloid from the Cat's Claw plant.” None of them say which one. Here's the chemistry that makes that omission the whole story — published data only, no health claims.

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AlkaloidWhat it isPublished receptor data
RhynchophyllineAn oxindole alkaloid found in Uncaria species (cat’s claw and relatives)No measurable opioid-receptor binding in published data
MitraphyllineThe oxindole alkaloid cat’s-claw supplements have cited for decadesNo measurable opioid-receptor binding in published data
Corynoxine BA related oxindole reported by industry sources as the compound new “cat’s claw” tablet products are built aroundReported as an opioid-active mu partial agonist — with no published human safety or dosing data as an isolated compound

Chemistry and published findings only — no health claims, no dosing guidance, ever.

Why every label says “an indole alkaloid” and stops there

If a tablet contained mitraphylline or rhynchophylline — the alkaloids cat’s claw is actually known for — naming them would cost nothing. They’re legal, decades-familiar, and inert at opioid receptors in published data. The brands don’t name them. They market a kratom-like experience from an unnamed “indole alkaloid,” which industry reporting identifies as corynoxine B in at least part of the category — an opioid-active compound with no published human safety record as an isolate.

Add the public record — Utah Poison Control’s July 2026 alert on adulterated products in this category, the Missouri Attorney General’s investigation into manufacturers — and the picture is the 7-OH cycle replaying one compound over. When enforcement arrives, the what-changed page for this wave is already written; you’re reading its chemistry section.

The brand pages in this cluster

The overview: cat’s claw vs kratom. The plant itself: Uncaria tomentosa, explained. The named brands: Dopium, Fuzziez, Buzzers & Homiez. And the lane with paperwork: Hydroxie Mitragynine-A and Dozo MG-X, third-party tested, shipped nationwide.

The alkaloids, answered

What alkaloids are actually in cat’s claw?
The named ones are oxindole alkaloids — mitraphylline and rhynchophylline chief among them. These are what supplement-aisle cat’s claw has cited for decades, and published receptor data shows neither has measurable binding at opioid receptors. That’s why genuine cat’s claw was never part of the kratom conversation until this year.
What is corynoxine B?
A related oxindole alkaloid that industry reporting identifies as the compound some new “cat’s claw” tablet products are built around. Unlike mitraphylline and rhynchophylline, corynoxine B is reported to be opioid-active — a mu-receptor partial agonist. There is no published human safety, dosing, or long-term data on it as an isolated compound. We make no claims about which brands contain it; most don’t name their alkaloid at all, which is the point.
Is corynoxine B legal?
It isn’t currently a scheduled substance — which is precisely why products are reportedly being built on it after the August 2026 scheduling of 7-OH. Whether that lasts is another question: the 7-OH cycle (poison-control alerts, an AG investigation, then federal action) is the obvious precedent, and the same early signals already exist for this category. General information, not legal advice.
Why does “which alkaloid” matter so much?
Because “cat’s claw extract” on a label can describe two completely different products: a mild herb with decades of shelf history, or an isolated opioid-active compound with no safety record, no established dosing, and nothing on the label saying so. The only thing that distinguishes them from the outside is a third-party lab panel naming the compound and the amount. That’s the standard we hold our own menu to.
What do you carry?
Two lanes. The mitragynine lane — the kratom leaf’s primary, naturally occurring alkaloid, not part of the federal 7-OH action: Hydroxie Mitragynine-A chewables and Dozo MG-X extract tabs, both third-party tested with panels we’ll send you on request. And in the cat’s-claw lane, blend. IndoBlend and LOADED Botanical Blend chewables — label facts on their brand pages, the documentation question answered straight when you text us. Shipped nationwide in plain unmarked packaging.

Named compounds. Published panels.

Lab-tested mitragynine, shipped nationwide. Most orders ship within 1 business day.

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