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25B-NBOMe can be fatal at heavy doses.[1]

It is strongly discouraged to take large amounts of this substance or to insufflate (snort) it. Please see this section for more details.

Summary sheet: 25B-NBOMe
Chemical Nomenclature
Common names 25B-NBOMe
Substitutive name 2C-B-NBOMe, BOM 2-CB, Cimbi-36, New Nexus, Nova
Systematic name 2-(4-Bromo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl) methyl]ethanamine
Class Membership
Psychoactive class Psychedelic
Chemical class Phenethylamine
Routes of Administration

WARNING: Always start with lower doses due to differences between individual body weight, tolerance, metabolism, and personal sensitivity. See responsible use section.

Threshold 50 - 100 µg
Light 100 - 300 µg
Common 300 - 500 µg
Strong 500 - 700 µg
Heavy 25B-NBOMe can be fatal at heavy doses.[1]
Total 8 - 12 hours
Onset 20 - 40 minutes
Come up 30 - 90 minutes
Peak 4 - 6 hours
Offset 2 - 4 hours
After effects 2 - 6 hours
Threshold 25 - 50 µg
Light 50 - 200 µg
Common 200 - 350 µg
Strong 350 - 500 µg
Heavy 25B-NBOMe can be fatal at heavy doses.[1]
Total 8 - 12 hours
Onset 2 - 5 minutes
After effects 2 - 6 hours

DISCLAIMER: PW's dosage information is gathered from users and resources for educational purposes only. It is not a recommendation and should be verified with other sources for accuracy.

25B-NBOMe (also known as Cimbi-36 and 2C-B-NBOMe) is novel synthetic psychedelic substance of the phenethylamine chemical class. It produces an array of visually-dominant and stimulating psychedelic effects when administered.

The name 25B-NBOMe, which short-hand for 2C-B-NBOMe, is a derivative of the phenethylamine psychedelic 2C-B. It was discovered in 2004 by Ralf Heim at the Free University of Berlin.[2] It acts as a potent partial agonist for the 5-HT2A receptor.[3] It has been used in clinical trials with an evaluation dose for safety consideration to humans of only 1 microgram. Such a dose was determined to be only 1/300th the dose expected to be hallucinogenic to humans and that recreational use would greatly exceed doses determined to be safe to humans.[3]

Anecdotal reports from users suggest 25B-NBOMe to be an active hallucinogen at a dose of as little as 250–500 µg, making it a similar potency to other phenethylamine derived hallucinogens such as Bromo-DragonFLY.[4] It is worth noting that compounds of the NBOMe class are not orally active and should therefore be taken sublingually by placing the substance into one's mouth and allowing it to slowly absorb over a period of 15-30 minutes.

This substance had no history of human use before being sold online as a designer drug in 2010.[citation needed] Extremely little is known about the pharmacological properties, metabolism, and toxicity of 25B-NBOMe in humans, and numerous members of the 25x-NBOMe series have been associated with hospitalizations and deaths. Along with its highly sensitive dose-response and unpredictable effects, many reports also suggest that this substance may be overly difficult to use safely. Therefore it is highly advised to approach this poorly understood, potentially deadly psychedelic substance with the proper amount of precaution and harm reduction practices if choosing to use it.


A comparison of 25B-NBOMe and 2C-B.

25B-NBOMe or 2C-B-NBOMe is a serotonergic N-benzyl derivative of the substituted phenethylamine psychedelic known as 2C-B. 25B-NBOMe is a substituted phenethylamine with methoxy groups CH3O- attached to carbons R2 and R5 as well as a bromine atom attached to carbon R4. It differs from 2C-B structurally through a substitution on the amine (NH2) with a 2-methoxybenzyl (BOMe) group. 25B-NBOMe shares this 2-methoxybenzyl substitution with other chemicals of the NBOMe family. This NBOMe addition contains a methoxy ether CH3O- bound to a benzene ring at R2.


Further information: Serotonergic psychedelic

25B-NBOMe has efficacy at the 5-HT2A receptor where it acts as a potent partial agonist.[5][6][7][8] However, the role of these interactions and how they result in the psychedelic experience continues to remain elusive.

Subjective effects

The effects listed below are based upon the subjective effects index and personal experiences of PsychonautWiki contributors. These effects should be taken with a grain of salt and will rarely (if ever) occur all at once, but heavier doses will increase the chances of inducing a full range of effects. Likewise, adverse effects become much more likely on higher doses and may include serious injury or death.

Physical effects

Visual effects

Cognitive effects

Experience reports

There are currently no anecdotal reports which describe the effects of this compound within our experience index. Additional experience reports can be found here:

Toxicity and harm potential

25B-NBOMe is a relatively new substance, and little is known about its pharmacological risks or its interaction with other substances. The lethal dosage has not yet been determined. One case has been reported on where 25B-NBOMe was identified as the cause of death for a 17-year-old boy.[9]

It is advised that due to 25B-NBOMe's extreme potency it should not be insufflated as this method of administration is potentially fatal at heavy dosages.[10]

25B-NBOMe has been used in clinical trials with an evaluation dose for safety consideration to humans of only 1 microgram; Such a dose is 300× lower than the dose expected to be hallucinogenic to humans and it is expected that recreational use would greatly exceed doses determined to be safe to humans.[11]

It is strongly recommended that one use harm reduction practices when using this substance.

Tolerance and addiction potential

25B-NBOMe is not habit-forming and the desire to use it can actually decrease with use. It is most often self-regulating.

Tolerance to the effects of 25B-NBOMe are built almost immediately after ingestion. After that, it takes about 1 week for the tolerance to be reduced to half and 2 weeks to be back at baseline (in the absence of further consumption). 25B-NBOMe presents cross-tolerance with all psychedelics, meaning that after the consumption of 25B-NBOMe all psychedelics will have a reduced effect.

Dangerous interactions

Although many psychoactive substances are safe to use on their own, they can quickly become dangerous or even life-threatening when combined with other substances. The following lists some known dangerous combinations, but may not include all of them. A combination that appears to be safe in low doses can still increase the risk of injury or death. Independent research should always be conducted to ensure that a combination of two or more substances is safe to consume.


  • Austria: 25B-NBOMe is illegal to possess, produce and sell under the NPSG (Neue-Psychoaktive-Substanzen-Gesetz Österreich).[citation needed]
  • Brazil - Possession, production and sale is illegal as it is listed on Portaria SVS/MS nº 344.[13]
  • China: As of October 2015 25B-NBOMe is a controlled substance in China.[14]
  • Germany - Possession, production and sale is illegal.[15]
  • United Kingdom - 25B-NBOMe is a Class A drug in the United Kingdom as a result of the N-benzylphenethylamine catch-all clause.[16]
  • Sweden: 25B-NBOMe is classed as Schedule I.[17]
  • United States: On Nov 15, 2013, the DEA added 25B-NBOMe to Schedule I using their emergency scheduling powers, making it "temporarily" in Schedule I for 2 years.[18]
  • Latvia: 25B-NBOMe is a Schedule I controlled substance.[19]
  • New Zealand: 25B-NBOMe is a Schedule 2 controlled substance in New Zealand.[20]
  • Canada: 25B-NBOMe would be considered Schedule III as it is a derivative of 2,5-dimethoxyphenethylamine.[21]
  • Italy: In Italy 25B-NBOMe is a Schedule 1 controlled substance, meaning it's illegal in this state.[22]

See also

External links


  1. 1.0 1.1 1.2 Other or Unknown NBOMe Compound Fatalities / Deaths by Erowid | https://www.erowid.org/chemicals/nbome/nbome_death.shtml
  2. Ralf Heim (February 28, 2010). "Synthese und Pharmakologie potenter 5-HT2A-Rezeptoragonisten mit N-2-Methoxybenzyl-Partialstruktur. Entwicklung eines neuen Struktur-Wirkungskonzepts." (in German). diss.fu-berlin.de. Retrieved 2013-05-10.
  3. 3.0 3.1 Hansen, M.; Phonekeo, K.; Paine, J. S.; Leth-Petersen, S.; Begtrup, M.; Bräuner-Osborne, H.; Kristensen, J. L. (2014). "Synthesis and Structure-Activity Relationships of N-Benzyl Phenethylamines as 5-HT2A/2C Agonists". ACS Chemical Neuroscience. 5 (3): 243–9. PMID 24397362. https://doi.org/10.1021/cn400216u
  4. Bromo-Dragonfly Dosage by Erowid | https://erowid.org/chemicals/bromo_dragonfly/bromo_dragonfly_dose.shtml
  5. Synthesis and pharmacology of potent 5-HT 2A receptor agonists with N-2-methoxybenzyl partial structure | http://www.diss.fu-berlin.de/diss/receive/FUDISS_thesis_000000001221
  6. Theoretical study of the interaction of agonists with the 5-HT2A receptor | http://epub.uni-regensburg.de/12119/
  7. Theoretical studies on the interaction of partial agonists with the 5-HT2A receptor | http://link.springer.com/article/10.1007%2Fs10822-010-9400-2
  8. Synthesis and Structure–Activity Relationships of N-Benzyl Phenethylamines as 5-HT2A/2C Agonists | http://pubs.acs.org/doi/abs/10.1021/cn400216u
  9. Designer Drug Identified As Cause Of Plano Teen’s Death | http://dfw.cbslocal.com/2015/02/19/designer-drug-identified-as-cause-of-plano-teens-death/
  10. http://www.erowid.org/chemicals/nbome/nbome_death.shtml
  11. Preclinical Safety Assessment of the 5-HT2A Receptor Agonist PET Radioligand [11C]Cimbi-36 | https://bitnest.netfirms.com/external.php?id=%257DbxUgX%255DCY%2504%2505wzx%2519%2505VYL%2502RI%257E%2560d
  12. Talaie, H., Panahandeh, R., Fayaznouri, M. R., Asadi, Z., & Abdollahi, M. (2009). Dose-independent occurrence of seizure with tramadol. Journal of medical toxicology, 5(2), 63-67. doi:10.1007/BF03161089
  13. http://portal.anvisa.gov.br/documents/10181/3115436/%281%29RDC_130_2016_.pdf/fc7ea407-3ff5-4fc1-bcfe-2f37504d28b7
  14. 关于印发《非药用类麻醉药品和精神药品列管办法》的通知 | http://www.sfda.gov.cn/WS01/CL0056/130753.html
  15. BtMG Anlage I | https://www.gesetze-im-internet.de/btmg_1981/anlage_i.html
  16. United Kingdom. (2014). Misuse of Drugs Act 1971 (S.I. 2014/1106). London: The Stationery Office Limited. Retrieved July 5, 2017, from http://www.legislation.gov.uk/uksi/2014/1106/made
  17. Läkemedelsverkets författningssamling - http://www.lakemedelsverket.se/upload/lvfs/LVFS_2013-15.pdf
  18. http://www.justice.gov/dea/divisions/hq/2013/hq111513.shtml
  19. Noteikumi par Latvijā kontrolējamajām narkotiskajām vielām, psihotropajām vielām un prekursoriem (2,5-Dimetoksifeniletānamīni) | http://likumi.lv/doc.php?id=121086
  20. http://www.legislation.govt.nz/act/public/1975/0116/latest/whole.html#DLM436576
  21. Controlled Drugs and Substances Act (S.C. 1996, c. 19) |http://laws-lois.justice.gc.ca/eng/acts/C-38.8/page-12.html#h-28
  22. Tabella 1 Stupefacenti dello Stato Italiano |http://www.salute.gov.it/imgs/C_17_pagineAree_3729_listaFile_itemName_0_file.pdf