RESEARCH MONOGRAPH · KDC-MN-156

7-Hydroxymitragynine

May 9, 2026 Kodiac biolabs Research Revised May 30, 2026 2 min read

Our opinion on this compound

56/100

The metabolite that does most of the work in kratom, with a much more concerning receptor pharmacology than the parent

7-Hydroxymitragynine is the CYP3A4-generated metabolite of mitragynine, and it's substantially more potent and more efficacious at the mu-opioid receptor than the parent alkaloid. Where mitragynine is a low-efficacy partial agonist, 7-hydroxy is closer to a full agonist with potency in the morphine range or higher at MOR. So when people consume kratom and the pharmacological effects build over time, a meaningful portion of the activity is being driven by this metabolite rather than by the parent compound directly.

The Andrew Kruegel group at Columbia and the Susruta Majumdar group at MSK have done extensive structure-activity and signaling work on the mitragynine alkaloid family. 7-hydroxymitragynine is closer to traditional mu-opioid agonist pharmacology than mitragynine itself, with less of the G-protein biased signaling profile that the parent compound shows.

What we like: as a pharmacological probe, 7-hydroxymitragynine is useful for studying mu-opioid receptor signaling. The selectivity profile is reasonably clean (high affinity for MOR, lower at delta and kappa). The structural features driving its pharmacology have been mapped to some degree.

What we dont like: the recent commercialization of isolated 7-hydroxymitragynine as a consumer product is genuinely concerning. The compound has full-agonist-like pharmacology at the receptor that drives opioid abuse and respiratory depression, but is being sold in formats that bypass the regulatory framework that exists around traditional opioids. The harm-reduction case that originally protected kratom commercially (whole-plant partial agonist) doesnt extend to isolated 7-hydroxy in the same way, because the pharmacological profile is fundamentally different.

Mechanism: mu-opioid receptor agonism with conventional G-protein and beta-arrestin signaling, less of the bias that the parent compound shows. Reasonably mapped at this point.

Sourcing: research-grade 7-hydroxymitragynine is available from a few specialty suppliers for research use. The proliferating consumer products are a separate and problematic category. Verify provenance carefully.

Genuinely interesting as an opioid pharmacology research tool. Genuinely concerning as a commercial product. The distinction between the two contexts matters a lot here.

Evidence: 50
Mechanism: 75
Reliability: 70
Safety: 35
Sourcing: 50
Value: 50
Signal: 65
Staying power: 50

Plain-language summary Intrigue 60 / 100

7-Hydroxymitragynine is the more potent mu-opioid agonist alkaloid in kratom and is also a metabolite of mitragynine. It is sold as a concentrated alkaloid product with greater opioid activity than whole kratom. Not stocked by Kodiac. This monograph is provided for research and educational reference.

Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.

Indole alkaloid / mu-opioid agonist

The active metabolite of mitragynine with higher mu-opioid receptor affinity, present in low concentrations in kratom leaf and concentrated in some kratom extracts.

Abstract

7-Hydroxymitragynine (7-OH; CAS 174418-82-7) is the principal active metabolite of mitragynine, formed by hepatic CYP3A4 hydroxylation. The compound has higher mu-opioid receptor affinity and analgesic potency than mitragynine itself, and accounts for a substantial fraction of kratom's clinical effect where the metabolic conversion is significant. 7-OH is present in low concentrations in fresh kratom leaf but can accumulate in stored or processed kratom products and is concentrated in some "enhanced" or "extract" kratom products sold commercially. Concentrated 7-OH products carry substantially higher abuse and dependence liability than whole-leaf kratom. The compound is sold as a research chemical/concentrated kratom product.

Mechanism of action

Mu-opioid receptor agonist with higher potency than mitragynine. Active metabolite of mitragynine via hepatic CYP3A4.

Reported research dose ranges

Reported research dose ranges in the literature are very low (sub-milligram); concentrated products are hazardous.

References

Kruegel AC, et al. As above.

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KDC-MN-156

The full reference document is provided strictly for research use only. It reports research dose ranges from the published literature, not instructions for use in humans or animals.

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FOR RESEARCH USE ONLY. Not for medical, diagnostic, or therapeutic purposes. Not for human consumption. All information is provided for research and educational purposes only.

Kodiac sells research compounds for investigative use only.

7-Hydroxymitragynine

Abstract

Mechanism of action

Reported research dose ranges

References

Read the full monograph

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Abstract

Mechanism of action

Reported research dose ranges

References

Read the full monograph

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