7-Hydroxymitragynine

Last updated

7-Hydroxymitragynine
7-hydroxymitragynine2DACS.svg
7-OH-mitragynine.png
Clinical data
Other names7-OH; 7α-Hydroxy-7H-mitragynine; [1] 9-Methoxycorynantheidine hydroxyindolenine [1]
Dependence
liability
High
Addiction
liability
High [2]
Routes of
administration
Oral
Drug class Opioid
ATC code
  • None
Legal status
Legal status
  • BR: Class F1 (Prohibited narcotics)
  • US:Unscheduled
Pharmacokinetic data
Metabolites Mitragynine pseudoindoxyl
Identifiers
  • Methyl (2E)-2-[(2S,3S,7aS,12bS)-3-ethyl-7a-hydroxy-8-methoxy-1,2,3,4,6,7,7a,12b-octahydroindolo[2,3-a]quinolizin-2-yl]-3-methoxyprop-2-enoate
CAS Number
PubChem CID
ChemSpider
UNII
ChEMBL
CompTox Dashboard (EPA)
Chemical and physical data
Formula C23H30N2O5
Molar mass 414.502 g·mol−1
3D model (JSmol)
  • CC[C@@H]1CN2CC[C@@]3(O)C(=Nc4cccc(OC)c34)[C@@H]2C[C@@H]1\C(=C/OC)C(=O)OC

  • CC[C@@H]1CN2CC[C@@]3(O)C(=NC4=CC=CC(OC)=C34)[C@@H]2C[C@@H]1\C(=C/OC)C(=O)OC
  • InChI=1S/C23H30N2O5/c1-5-14-12-25-10-9-23(27)20-17(7-6-8-19(20)29-3)24-21(23)18(25)11-15(14)16(13-28-2)22(26)30-4/h6-8,13-15,18,27H,5,9-12H2,1-4H3/b16-13+/t14-,15+,18+,23+/m1/s1 Yes check.svgY
  • Key:RYENLSMHLCNXJT-CYXFISRXSA-N Yes check.svgY

7-Hydroxymitragynine (7-OH-MIT, often simply referred to as 7-OH) is a terpenoid indole alkaloid present in the plant Mitragyna speciosa (the leaves of which are commonly known as kratom ). [3] It was first described in 1994. [4] In humans, it is produced as an active metabolite of mitragynine via hepatic oxidation. [5] 7-OH exhibits greater binding affinity to μ-opioid receptors (MOR) than mitragynine.[ citation needed ]

Contents

Pharmacology

7-OH-MIT, like mitragynine, appears to be a mixed opioid receptor agonist/antagonist, with recent research indicating that it acts as a partial agonist at μ-opioid receptors and as a competitive antagonist at δ- and κ-opioid receptors. [6] [7] Both 7-OH-MIT and mitragynine do not appear to activate the β-arrestin pathway, distinguishing it from traditional opiate and opioid chemicals. [6] A study has found the binding affinity of 7-OH-MIT to be μ-opioid receptor (MOR) 37 (± 4) nM and δ-opioid receptor (DOR) 91 (± 8) nM and κ-opioid receptor (KOR) 132 (± 7) nM. [8] Another study found the binding affinity of 7-OH-MIT to be MOR 16 (± 1) nM and DOR 137 (± 21) nM and KOR 133 (± 37) nM. [9] Another study found the binding affinity of 7-OH-MIT to be MOR 13.5 nM, DOR 155 nM, and KOR 123 nM. [9] Cross-tolerance to morphine was evident in mice rendered tolerant to 7-hydroxymitragynine and vice versa. Naloxone-induced withdrawal signs were elicited equally in mice chronically treated with 7-hydroxymitragynine or morphine. [10]

Synthesis

In natural kratom leaves, 7-hydroxymitragynine is only present in small amounts, comprising less than 2% of overall alkaloid content. [11] Therefore, extracting 7-OH-MIT in high concentrations directly from natural kratom leaves is not practical. Instead, 7-hydroxymitragynine can be produced semisynthetically via the oxidation of mitragynine. [5]

Society and culture

7-OH has been rising in popularity as a recreational drug, particularly in the United States. Its ability to bind to opioid receptors can cause addictive effects. In an electrical stimulation test using guinea-pig ileum, 7-OH performed 13 times greater pain relief than that of morphine. [12] The drug's novelty has meant that it has increasingly been sold unregulated over the counter in gas stations and smoke shops, often in highly concentrated "candy-like" or pill form alongside kratom powder and other supplements with little to no information provided to consumers about its effects. [11]

According to the United States Poison Control Center, the number of cases relating to kratom-based products such as 7-OH have increased from under 200 in 2014 to 1600 in 2024, with approximately 40% of 7-OH reports coming from individuals who were abusing the drug. [13]

United States

In July 2025, the Food and Drug Administration (FDA) formally recommended that the Drug Enforcement Administration (DEA) classify 7-hydroxymitragynine as a controlled substance. [14] This action is not directed toward Mitragyna speciosa itself, which will remain unaffected by regulation of 7-OH. [15] Despite claims by marketers for products that contain 7-OH that they can be used to treat anxiety and pain, the drug is not approved by the FDA for any medical use or as a food supplement. [16]

On August 13, 2025, Florida attorney general James Uthmeier announced an emergency rule placing 7-hydroxymitragynine into schedule I status under Florida state law, effectively outlawing the substance and removing it from all headshops and similar stores from the state. [17] [18] [19]

Research

Studies on 7-hydroxymitragynines safety have been unable to identify an LD50 orally with no deaths occurring. [20] 7-hydroxymitragynine has been described as a "prototypical" compound to develop a new generation of opioids with an improved safety profile. [21]

See also

References

  1. 1 2 Chemical Abstracts Service: Columbus, OH, 2004; RN 174418-82-7 (accessed via SciFinder Scholar, version 2007.3; November 30, 2011)
  2. Reissig CJ, Chiapperino D, Seitz A, Lee R, Radin R, McAninch J. 7-Hydroxymitragynine (7-OH): An Assessment of the Scientific Data and Toxicological Concerns Around an Emerging Opioid Threat (Report).
  3. Matsumoto K, Horie S, Ishikawa H, Takayama H, Aimi N, Ponglux D, et al. (March 2004). "Antinociceptive effect of 7-hydroxymitragynine in mice: Discovery of an orally active atypical opioid analgesic from the Thai medicinal herb Mitragyna speciosa". Life Sciences. 74 (17): 2143–2155. doi:10.1016/j.lfs.2003.09.054. PMID   14969718.
  4. Ponglux D, Wongseripipatana S, Takayama H, Kikuchi M, Kurihara M, Kitajima M, et al. (December 1994). "A New Indole Alkaloid, 7 alpha-Hydroxy-7H-mitragynine, from Mitragyna speciosa in Thailand". Planta Medica. 60 (6): 580–581. Bibcode:1994PlMed..60..580P. doi:10.1055/s-2006-959578. PMID   17236085. S2CID   260252538.
  5. 1 2 Karunakaran T, Marimuthu Y, Rusmadi NN, Firouz NS, Jenis J, Kumar US, et al. (2024-10-10). "Chemistry and toxicity of 7-hydroxymitragynine (7-OHMG): an updated review on the oxidized derivative of mitragynine". Phytochemistry Reviews. Bibcode:2024PChRv.tmp..145G. doi:10.1007/s11101-024-10029-x. ISSN   1572-980X.{{cite journal}}: CS1 maint: bibcode (link)
  6. 1 2 Eastlack SC, Cornett EM, Kaye AD (June 2020). "Kratom-Pharmacology, Clinical Implications, and Outlook: A Comprehensive Review". Pain and Therapy. 9 (1): 55–69. doi:10.1007/s40122-020-00151-x. PMC   7203303 . PMID   31994019.
  7. Chang-Chien GC, Odonkor CA, Amorapanth P (2017). "Is Kratom the New 'Legal High' on the Block?: The Case of an Emerging Opioid Receptor Agonist with Substance Abuse Potential". Pain Physician. 20 (1): E195 –E198. doi: 10.36076/ppj.2017.1.E195 . PMID   28072812.
  8. Váradi A, Marrone GF, Palmer TC, Narayan A, Szabó MR, Le Rouzic V, et al. (2016). "Mitragynine/Corynantheidine Pseudoindoxyls as Opioid Analgesics with Mu Agonism and Delta Antagonism, Which do Not Recruit β-Arrestin-2". Journal of Medicinal Chemistry. 59 (18): 8381–8397. doi:10.1021/acs.jmedchem.6b00748. PMC   5344672 . PMID   27556704.
  9. 1 2 Takayama H, Ishikawa H, Kurihara M, Kitajima M, Aimi N, Ponglux D, et al. (2002). "Studies on the Synthesis and Opioid Agonistic Activities of Mitragynine-Related Indole Alkaloids: Discovery of Opioid Agonists Structurally Different from Other Opioid Ligands" . Journal of Medicinal Chemistry. 45 (9): 1949–1956. doi:10.1021/jm010576e. PMID   11960505.
  10. Matsumoto K, Horie S, Takayama H, Ishikawa H, Aimi N, Ponglux D, et al. (2005). "Antinociception, tolerance and withdrawal symptoms induced by 7-hydroxymitragynine, an alkaloid from the Thai medicinal herb Mitragyna speciosa". Life Sciences. 78 (1): 2–7. doi:10.1016/j.lfs.2004.10.086. PMID   16169018.
  11. 1 2 Reissig CJ, Chiapperino D, Seitz A, Lee R, Radin R, McAninch J (2025). "7-Hydroxymitragynine (7-OH): An Assessment of the Scientific Data and Toxicological Concerns Around an Emerging Opioid Threat". Food and Drug Administration : 4. 7-OH is a naturally occurring substance in the kratom plant (Mitragyna speciosa), but only a minor constituent that comprises less than 2% of the total alkaloid content in natural kratom leaves.
  12. Reissig CJ, Chiapperino D, Seitz A, Lee R, Radin R, McAninch J. 7-Hydroxymitragynine (7-OH): An Assessment of the Scientific Data and Toxicological Concerns Around an Emerging Opioid Threat (Report). U.S. Drug and Food Administration (FDA) Center for Drug Evaluation and Research (CDER). p. 14. 7-OH displayed approximately 13-fold greater potency than morphine
  13. Office of the Commissioner (2025-07-30). "Hiding in Plain Sight: 7-OH Products". FDA. Retrieved 2025-08-05.
  14. "US health officials crack down on kratom-related products after complaints from supplement industry". WHEC. Associated Press. 2025-07-29. Retrieved 2025-07-29.
  15. U.S. Food and Drug Administration (July 29, 2025). "FDA Takes Steps to Restrict 7-OH Opioid Products Threatening American Consumers". FDA. Retrieved August 18, 2025.
  16. "Products Containing 7-OH Can Cause Serious Harm". Drugs.com. Retrieved 2025-08-05.
  17. "Attorney General James Uthmeier Files Emergency Rule; Immediately Removing Dangerous 7-OH from Store Shelves | My Florida Legal".
  18. "Florida AG announces ban on "7-OH" products". 13 August 2025.
  19. <https://www.fox13news.com/news/florida-ag-uthmeier-taking-emergency-action-against-new-synthetic-drug-7-oh
  20. Smith LC, Lin L, Hwang CS, Zhou B, Kubitz DM, Wang H, et al. (2019). "Lateral Flow Assessment and Unanticipated Toxicity of Kratom". Chemical Research in Toxicology. 32 (1): 113–121. doi:10.1021/acs.chemrestox.8b00218. PMC   6662923 . PMID   30380840.
  21. Matsumoto K, Narita M, Muramatsu N, Nakayama T, Misawa K, Kitajima M, et al. (2014). "Orally active opioid μ/δ dual agonist MGM-16, a derivative of the indole alkaloid mitragynine, exhibits potent antiallodynic effect on neuropathic pain in mice". The Journal of Pharmacology and Experimental Therapeutics. 348 (3): 383–392. doi:10.1124/jpet.113.208108. PMC   6067406 . PMID   24345467.