25B-NBOMe

Use and effects

The dose range of 25B-NBOMe has been given as 50 to 700μg sublingually, with a typical dose estimate of 400μg. Doses over 800μg are said to be very strong. Its onset sublingually is said to be 15minutes to 2hours and to be longer than that of LSD.

Toxicity and harm potential

Neurotoxic and cardiotoxic actions

Emergency treatment

Interactions

Pharmacology

Pharmacodynamics

25B-NBOMe is a selective serotonin 5-HT2 receptor agonist. It showed roughly the same affinity for the serotonin 5-HT2A, 5-HT2B, and 5-HT2C receptors in one study (Ki = 0.5–1.7nM). However, in another study, it showed 12- to 20-fold selectivity for the serotonin 5-HT2A receptor (Ki = 0.5nM) over the serotonin 5-HT2B and 5-HT2C receptors (Ki = 10 and 6.2nM, respectively). The drug is highly selective for the serotonin 5-HT2 receptors over a variety of other serotonin receptors, as well as over various other monoamine receptors and over the monoamine transporters (200-fold selectivity). However, 25B-NBOMe is a low-potency partial agonist of the rat and mouse trace amine-associated receptor 1 (TAAR1) but is inactive at the human TAAR1.

25B-NBOMe has been found to increase levels of glutamate, serotonin, dopamine, and acetylcholine in the frontal cortex, striatum, and nucleus accumbens in rats. Other serotonergic psychedelics like LSD and DOI have also been found to increase glutamate levels in the frontal cortex in rodents, and this effect can be blocked by the serotonin 5-HT2A receptor antagonist volinanserin (MDL-100,907). 25B-NBOMe shows an inverted U-shaped dose–response curve in terms of neurotransmitter elevations in multiple brain areas. This may be due to an inhibitory effect of serotonin 5-HT2C receptors at higher doses. 25B-NBOMe produces the head-twitch response, a behavioral proxy of psychedelic effects, in rodents, and this effect shows an inverted U-shaped dose–response curve similarly to its influences on neurotransmitter levels. The head twitches and hallucinogenic effects of 25B-NBOMe may be due to increased cortical glutamate release secondary to serotonin 5-HT2A receptor activation. The effects of 25B-NBOMe on levels of other neurotransmitters, such as accumbal dopamine concentrations, may also be mediated by activation of serotonin 5-HT2A receptors and glutamate elevation. It has been suggested that the serotonin elevations with 25B-NBOMe may be involved in its production of serotonin syndrome in humans.

Unlike many other serotonergic psychedelics, 25B-NBOMe has been found to produce reinforcing effects in rodents, including conditioned place preference (CPP) and self-administration, and hence may have misuse potential. Accordingly, 25B-NBOMe robustly increased dopamine levels in the nucleus accumbens in rodents similarly to but a lesser extent than methamphetamine, and its reinforcing effects could be blocked by the dopamine receptor antagonists SCH-23390 and haloperidol. Serotonin 5-HT2A receptor activation is known to increase dopamine release in the mesolimbic pathway. However, the reinforcing effects of 25B-NBOMe were not blocked by the selective serotonin 5-HT2A receptor antagonist ketanserin. Similarly to 25B-NBOMe, 25N-NBOMe has also shown reinforcing effects in rodents. More research is needed to elucidate how 25B-NBOMe and other NBOMe drugs produce reinforcing effects in animals.

25B-NBOMe has been found to decrease locomotor activity in rodents.

25B-NBOMe has been found to produce neurotoxicity in rodents.

Chemistry

Analogues

Analogues of 25B-NBOMe include 2C-B, DOB, 25B-NB, DOB-NBOMe, 25I-NBOMe, 25C-NBOMe, 25B-NBOH, 25B-NBF, 2CBFly-NBOMe, 2CBCB-NBOMe (NBOMe-TCB-2), DMBMPP, and 25B-NAcPip, among others.

History

25B-NBOMe was first described in the scientific literature, in the form of conference abstracts, by Ralf Heim and colleagues at the Free University of Berlin by 1999.

Society and culture

Legal status

Canada

As of October 31, 2016; 25B-NBOMe is a controlled substance (Schedule III) in Canada.

China

As of October 2015 25B-NBOMe is a controlled substance in China.

Czech Republic

25B-NBOMe is banned in the Czech Republic.

Finland

Scheduled in the "government decree on substances, preparations and plants considered to be narcotic drugs".

Russia

Banned as a narcotic drug since May 5, 2015.

Sweden

In Sweden, the Riksdag added 25B-NBOMe to schedule I ("substances, plant materials and fungi which normally do not have medical use") as narcotics in Sweden as of August 1, 2013, published by the Medical Products Agency in their regulation LVFS 2013:15 listed as 25B-NBOMe 2-(4-bromo-2,5-dimetoxifenyl)-N-(2-metoxibensyl)etanamin.

United Kingdom

United States

In November 2013, the U.S. Drug Enforcement Administration placed 25B-NBOMe (along with 25I-NBOMe and 25C-NBOMe) in Schedule I of the Controlled Substances Act, making it illegal to manufacture, buy, possess, process, or distribute.

Notes

References

References

1. Anvisa. (2023-07-24). "RDC Nº 804 - Listas de Substâncias Entorpecentes, Psicotrópicas, Precursoras e Outras sob Controle Especial". [[Diário Oficial da União]].
2. "Substance Details 25B-NBOMe".
3. (2009). "Theoretical study of the interaction of agonists with the 5-HT2A receptor". Universität Regensburg.
4. (January 2011). "Theoretical studies on the interaction of partial agonists with the 5-HT2A receptor". Journal of Computer-Aided Molecular Design.
5. (March 2014). "Synthesis and structure-activity relationships of N-benzyl phenethylamines as 5-HT2A/2C agonists". ACS Chemical Neuroscience.
6. (3 July 2014). "25C-NBOMe: preliminary data on pharmacology, psychoactive effects, and toxicity of a new potent and dangerous hallucinogenic drug". BioMed Research International.
7. (July 2014). "Serotonin 2A receptor agonist binding in the human brain with [¹¹C]Cimbi-36". Journal of Cerebral Blood Flow and Metabolism.
8. (November 2020). "25B-NBOMe, a novel N-2-methoxybenzyl-phenethylamine (NBOMe) derivative, may induce rewarding and reinforcing effects via a dopaminergic mechanism: Evidence of abuse potential". Addiction Biology.
9. (2010-12-16). "Design and Synthesis of Selective Serotonin Receptor Agonists for Positron Emission Tomography Imaging of the Brain.". University of Copenhagen.
10. (August 2013). "Preclinical safety assessment of the 5-HT2A receptor agonist PET radioligand [ 11C]Cimbi-36". Molecular Imaging and Biology.
11. "From molecule to man: The full CIMBI-36 story". cimbi.dk.
12. "Imanova announces the launch of a new imaging biomarker to investigate the serotonin system in psychiatric illness". imanova.co.uk.
13. (June 2019). "Psychedelic effects of psilocybin correlate with serotonin 2A receptor occupancy and plasma psilocin levels". Neuropsychopharmacology.
14. (October 2018). "Monoamine Transporter and Receptor Interaction Profiles in Vitro Predict Reported Human Doses of Novel Psychoactive Stimulants and Psychedelics". Int J Neuropsychopharmacol.
15. "25B-NBOMe (2C-B-NBOMe)".
16. (15 May 2025). "Kᵢ Database".
17. (June 2025). "Toxicodynamic insights of 2C and NBOMe drugs - Is there abuse potential?". Toxicol Rep.
18. (December 2015). "Receptor interaction profiles of novel N-2-methoxybenzyl (NBOMe) derivatives of 2,5-dimethoxy-substituted phenethylamines (2C drugs)". Neuropharmacology.
19. (April 2011). "Radiosynthesis and in vivo evaluation of a series of substituted 11C-phenethylamines as 5-HT (2A) agonist PET tracers". Eur J Nucl Med Mol Imaging.
20. (January 2013). "Extensive rigid analogue design maps the binding conformation of potent N-benzylphenethylamine 5-HT2A serotonin receptor agonist ligands". ACS Chem Neurosci.
21. Hansen, M. (2010). Design and Synthesis of Selective Serotonin Receptor Agonists for Positron Emission Tomography Imaging of the Brain: PhD Thesis. Faculty of Pharmaceutical Sciences, University of Copenhagen. https://bitnest.netfirms.com/external/Theses/Hansen2011
22. (March 2014). "Synthesis and structure-activity relationships of N-benzyl phenethylamines as 5-HT2A/2C agonists". ACS Chem Neurosci.
23. (August 2016). "Synthesis and evaluation of (18)F-labeled 5-HT2A receptor agonists as PET ligands". Nucl Med Biol.
24. (November 2016). "5-HT2A/5-HT2C Receptor Pharmacology and Intrinsic Clearance of N-Benzylphenethylamines Modified at the Primary Site of Metabolism". ACS Chem Neurosci.
25. (June 2017). "Detailed Characterization of the In Vitro Pharmacological and Pharmacokinetic Properties of N-(2-Hydroxybenzyl)-2,5-Dimethoxy-4-Cyanophenylethylamine (25CN-NBOH), a Highly Selective and Brain-Penetrant 5-HT2A Receptor Agonist". J Pharmacol Exp Ther.
26. (December 2020). "In vitro characterization of new psychoactive substances at the μ-opioid, CB1, 5HT1A, and 5-HT2A receptors-On-target receptor potency and efficacy, and off-target effects". Forensic Sci Int.
27. (October 2020). "In vitro structure-activity relationship determination of 30 psychedelic new psychoactive substances by means of β-arrestin 2 recruitment to the serotonin 2A receptor". Arch Toxicol.
28. (December 2017). "Measuring inhibition of monoamine reuptake transporters by new psychoactive substances (NPS) in real-time using a high-throughput, fluorescence-based assay". Toxicol in Vitro.
29. (April 2016). "In Vitro Characterization of Psychoactive Substances at Rat, Mouse, and Human Trace Amine-Associated Receptor 1". J Pharmacol Exp Ther.
30. (May 2023). "Off-target activity of NBOMes and NBOMe analogs at the µ opioid receptor". Arch Toxicol.
31. (December 2020). "DARK Classics in Chemical Neuroscience: NBOMes". ACS Chem Neurosci.
32. (December 2023). "Molecular and Medical Aspects of Psychedelics". Int J Mol Sci.
33. (2020). "NBOMes-Highly Potent and Toxic Alternatives of LSD". Front Neurosci.
34. (November 2020). "25B-NBOMe, a novel N-2-methoxybenzyl-phenethylamine (NBOMe) derivative, may induce rewarding and reinforcing effects via a dopaminergic mechanism: Evidence of abuse potential". Addict Biol.
35. (October 2019). "A novel designer drug, 25N-NBOMe, exhibits abuse potential via the dopaminergic system in rodents". Brain Res Bull.
36. (August 2017). "Locomotor and discriminative stimulus effects of four novel hallucinogens in rodents". Behav Pharmacol.
37. (April 2021). "Neurochemical and Behavioral Effects of a New Hallucinogenic Compound 25B-NBOMe in Rats". Neurotox Res.
38. (December 2023). "Hallucinogenic activity, neurotransmitters release, anxiolytic and neurotoxic effects in Rat's brain following repeated administration of novel psychoactive compound 25B-NBOMe". Neuropharmacology.
39. Heim, R., Pertz, H. H., & Elz, S. (1999). Preparation and in vitro pharmacology of novel secondary amine-type 5-HT2A receptor agonists: from submillimolar to subnanomolar activity. Arch. Pharm. Pharm. Med. Chem, 332, 34. https://bitnest.netfirms.com/external/Arch.Pharm.Pharm.Med.Chem/331.S1.34
40. (4 May 2016). "Regulations Amending the Food and Drug Regulations (Part J — 2C-phenethylamines)".
41. (27 September 2015). "关于印发《非药用类麻醉药品和精神药品列管办法》的通知". China Food and Drug Administration.
42. "Látky, o které byl doplněn seznam č. 4 psychotropních látek (příloha č. 4 k nařízení vlády č. 463/2013 Sb.)". Ministerstvo zdravotnictví.
43. "543/2008".
44. "Постановление Правительства РФ от 30.06.1998 N 681 "Об утверждении перечня наркотических средств, психотропных веществ и их прекурсоров, подлежащих контролю в Российской Федерации" (с изменениями и дополнениями)".
45. "Föreskrifter om ändring i Läkemedelsverkets föreskrifter (LVFS 2011:10) om förteckningar över narkotika;". lakemedelsverket.se.
46. "2016 - Final Rule: Placement of Three Synthetic Phenethylamines Into Schedule I".