Legal status
Legal status
  • AU: S4 (Prescription only)
  • US: Specifically unscheduled (but still a Schedule I analogue due to being a main metabolite of C-I ibogaine)
CAS Number 481-88-9 N
PubChem (CID) 3083548
ChemSpider 2340735 YesY
Chemical and physical data
Formula C19H24N2O
Molar mass 296.407 g/mol
3D model (Jmol) Interactive image
 NYesY (what is this?)  (verify)

Noribogaine, or 12-hydroxyibogamine, is the principal psychoactive metabolite of the hallucinogenic drug ibogaine. It is thought to be involved in the antiaddictive effects of ibogaine-containing plant extracts, such as Tabernanthe iboga.[1][2][3]

A recent study evaluated its effects on healthy volunteers at doses of 3–60 mg, finding no tolerability issues.[4] A slow half-life of 28–49 hours was seen with large volume of distribution.


Noribogaine is a potent serotonin reuptake inhibitor,[5] but does not affect the reuptake of dopamine.[6] Unlike ibogaine, noribogaine does not bind to the sigma-2 receptor.[7][8] Similarly to ibogaine, noribogaine acts as a weak NMDA receptor antagonist and binds to opioid receptors.[9] It has greater affinity for each of the opioid receptors than does ibogaine.[10]

κ-Opioid receptor

Recently, noribogaine has been determined to act as a biased agonist of the κ-opioid receptor (KOR).[11] It activates the G-protein (GDP-GTP exchange) signaling pathway with 75% the efficacy of dynorphin A (EC50 = 9 μM), but it is only 12% as efficacious at activating the β-arrestin pathway.[11] Moreover, due to its very low efficacy on the β-arrestin pathway, noribogaine blocked dynorphin A activation of the pathway (IC50 = 1 μM) and hence functioned as an antagonist of it.[11] The β-arrestin pathway is thought to be responsible for the dysphoric and aversive effects of KOR activation,[12] and its lack of activation by noribogaine may be the reason for the lack of dysphoric effects of the drug.[11] This biased agonist/antagonist action of noribogaine at the KOR is unique to it relative to other iboga alkaloids and related compounds such as ibogaine and 18-methoxycoronaridine (18-MC).[11] Moreover, it has been hypothesized that it may give noribogaine unique properties such that it may have the analgesic and antiaddictive effects of KOR agonists without the anxiogenic, dysphoric, or anhedonic effects that are typical of them.[11]

See also


  1. Glick SD, Maisonneuve IS (May 1998). "Mechanisms of antiaddictive actions of ibogaine". Annals of the New York Academy of Sciences. 844: 214–26. doi:10.1111/j.1749-6632.1998.tb08237.x. PMID 9668680.
  2. Baumann MH, Pablo J, Ali SF, Rothman RB, Mash DC (2001). "Comparative neuropharmacology of ibogaine and its O-desmethyl metabolite, noribogaine". The Alkaloids: Chemistry and Biology. 56: 79–113. doi:10.1016/S0099-9598(01)56009-5. PMID 11705118.
  3. Kubiliene A, Marksiene R, Kazlauskas S, Sadauskiene I, Razukas A, Ivanov L (2008). "Acute toxicity of ibogaine and noribogaine". Medicina (Kaunas, Lithuania). 44 (12): 984–8. PMID 19142057.
  4. "Ascending-dose study of noribogaine in healthy volunteers: Pharmacokinetics, pharmacodynamics, safety, and tolerability.". The Journal of Clinical Pharmacology. 55: 189–94. Oct 3, 2014. doi:10.1002/jcph.404. PMID 25279818.
  5. Max M. Houck (26 January 2015). Forensic Chemistry. Elsevier Science. pp. 164–. ISBN 978-0-12-800624-5.
  6. Baumann, Michael H.; Rothman, Richard B.; Pablo, John P.; Mash, Deborah C. (May 1, 2001). "In Vivo Neurobiological Effects of Ibogaine and Its O-Desmethyl Metabolite, 12-Hydroxyibogamine (Noribogaine), in Rats". Journal of Pharmacology and Experimental Therapeutics. 297 (2): 531–539. ISSN 1521-0103. PMID 11303040.
  7. Paul Gahlinger (30 December 2003). Illegal Drugs. Penguin Publishing Group. pp. 304–. ISBN 978-1-4406-5024-6.
  8. Kenneth R. Alper; Stanley D. Glick (2001). Ibogaine: Proceedings from the First International Conference. Gulf Professional Publishing. pp. 107–. ISBN 978-0-12-053206-3.
  9. Donald G. Barceloux (20 March 2012). Medical Toxicology of Drug Abuse: Synthesized Chemicals and Psychoactive Plants. John Wiley & Sons. pp. 869–. ISBN 978-0-471-72760-6.
  10. Pearl, S. M.; Herrick-Davis, K.; Teitler, M.; Glick, S. D. (Mar 27, 1995). "Radioligand-binding study of noribogaine, a likely metabolite of ibogaine". Brain Research. 675 (1-2): 342–344. doi:10.1016/0006-8993(95)00123-8. ISSN 0006-8993. PMID 7796150.
  11. 1 2 3 4 5 6 Maillet EL, Milon N, Heghinian MD, Fishback J, Schürer SC, Garamszegi N, Mash DC (2015). "Noribogaine is a G-protein biased κ-opioid receptor agonist". Neuropharmacology. 99: 675–88. doi:10.1016/j.neuropharm.2015.08.032. PMID 26302653.
  12. Ehrich JM, Messinger DI, Knakal CR, Kuhar JR, Schattauer SS, Bruchas MR, Zweifel LS, Kieffer BL, Phillips PE, Chavkin C (2015). "Kappa Opioid Receptor-Induced Aversion Requires p38 MAPK Activation in VTA Dopamine Neurons". J. Neurosci. 35 (37): 12917–31. doi:10.1523/JNEUROSCI.2444-15.2015. PMID 26377476.

This article is issued from Wikipedia - version of the 11/8/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.