25B-NBOMe, also known as NBOMe-2C-B, Cimbi-36, Nova, or BOM 2-CB, belongs to the phenethylamine psychedelic class and was initially discovered in 2004 by Ralf Heim at the Free University of Berlin. This compound functions as a potent full agonist for the 5HT2A receptor.
Anecdotal reports from users have suggested that 25B-NBOMe can induce hallucinogenic effects at doses as low as 250–500 µg, demonstrating similar potency to other phenethylamine-derived hallucinogens like Bromo-DragonFLY. The duration of its effects is reported to last approximately 12–16 hours. However, when used in the radiolabeled form for tracer doses, the parent compound is swiftly eliminated from the bloodstream.
Recent research conducted by Custodio et al. in 2019 examined the potential involvement of a dysregulated dopaminergic system, neuroadaptation, and changes in brain waves that might contribute to the rewarding and reinforcing properties of 25B-NBOMe in rodents.
A carbon-11 labelled version of this compound, [11C]Cimbi-36, was synthesized and validated as a radioactive tracer for positron emission tomography (PET) in Copenhagen. As a 5-HT2A receptor agonist PET radioligand, [11C]Cimbi-36 was believed to serve as a functional marker of these receptors and a potential indicator of serotonin release, allowing for the assessment of serotonin levels in vivo. Clinical trials involving [11C]Cimbi-36 as a PET ligand in humans are currently underway.

IUPAC name
CAS Number1026511-90-9 
PubChem CID9977044
CompTox Dashboard (EPA)DTXSID50907974
Chemical and physical data
Molar mass380.282 g·mol−1

Toxicity and harm potential

NBOMe compounds are frequently linked to severe toxicity and even fatal outcomes. Extensive research on the NBOMe family of compounds has revealed their potential for neurotoxic and cardiotoxic effects. Individuals who have encountered NBOMe compounds have commonly reported symptoms of autonomic dysfunction, including sympathomimetic toxicity, such as vasoconstriction, hypertension, and tachycardia, alongside hallucinations. These symptoms may be accompanied by restlessness, seizures, hyperthermia, profuse sweating, muscle rigidity, rhabdomyolysis, and, tragically, fatalities. Researchers have noted that intoxication with NBOMe often manifests signs of serotonin syndrome. Additionally, the likelihood of experiencing seizures is higher with NBOMes when compared to other psychedelics.

A concerning aspect is that NBOMe and NBOH compounds are sometimes deceitfully marketed as LSD, even sold on blotter papers. This misrepresentation is problematic because they differ significantly in terms of taste and safety profiles from genuine LSD. Despite their high potency, recreational doses of LSD have generally resulted in few cases of acute toxicity. Regrettably, fatalities attributed to NBOMe intoxication underscore that many individuals may have ingested the substance, believing it to be LSD. Researchers have also pointed out that individuals familiar with LSD may mistakenly assume NBOMe is equally safe. Tragically, apart from physical effects, there have been instances of self-harm and suicide linked to NBOMe use.

Due to limited documentation on NBOMe consumption, the long-term effects of these substances still need to be discovered. It’s worth noting that NBOMe compounds are not active when ingested orally, and they are typically consumed sublingually.: 3 Sublingual administration may lead to numbness of the tongue and mouth, followed by a distinctive metallic chemical taste. Researchers have identified this physical side effect as a key distinguishing factor between NBOMe compounds and LSD.

Neurotoxic and Cardiotoxic Actions:

Many NBOMe compounds exhibit high-potency agonist activity at various 5-HT receptors, and prolonged stimulation of the 5-HT2B receptor, in particular, can lead to cardiac valvulopathy, especially at high doses and with chronic use. Research has strongly associated 5-HT2B receptors with drug-induced valvular heart disease. The high affinity of NBOMe compounds for adrenergic α1 receptors contributes to their stimulant-like cardiovascular effects.

In laboratory studies, 25C-NBOMe demonstrated cytotoxicity in neuronal cell lines SH-SY5Y, PC12, and SN471. It was more potent than methamphetamine in reducing cell viability, with neurotoxicity involving the activation of the MAPK/ERK cascade and inhibition of the Akt/PKB signalling pathway. Furthermore, 25C-NBOMe, along with its derivative 25D-NBOMe, reduced the viability of cardiomyocytes H9c2 cells and downregulated the expression of p21 (CDC24/RAC)-activated kinase 1 (PAK1), an enzyme known for its cardiac protective effects.

Preliminary studies involving 25C-NBOMe have indicated toxicity to development, heart health, and brain health in zebrafish, rats, and Artemia salina. Further research is needed to determine the applicability of these toxicology results to humans and to assess the impact of the substance on pregnant women and their developing fetuses.

Emergency Treatment:

Currently, there are no specific antidotes for NBOMes, and the management of acute intoxication relies on symptomatic treatments. These may include the administration of benzodiazepines, antipsychotic medications, and antiarrhythmic agents like beta blockers. Some emergency interventions are tailored to address rhabdomyolysis, a condition that can lead to critical complications such as metabolic acidosis and acute kidney injury.

Legal status


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


Since May 5, 2015, 25B-NBOMe has been classified as a banned narcotic drug in Russia.


In Sweden, 25B-NBOMe was included in schedule I, encompassing substances, plant materials, and fungi typically devoid of medical use. This classification was implemented on August 1, 2013, and published by the Medical Products Agency under regulation LVFS 2013:15, listing it as 25B-NBOMe, which is 2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine.

United Kingdom:

In the United Kingdom, this substance is categorized as a Class A drug due to its inclusion in the N-benzyl phenethylamine catch-all clause in the Misuse of Drugs Act 1971.

United States:

In November 2013, the U.S. Drug Enforcement Administration designated 25B-NBOMe (alongside 25I-NBOMe and 25C-NBOMe) as Schedule I substances under the Controlled Substances Act, rendering their manufacture, purchase, possession, processing, and distribution illegal.


Since October 2015, 25B-NBOMe has been classified as a controlled substance in China.

Czech Republic:

The Czech Republic has also prohibited the use of 25B-NBOMe.


  • What is 25B-NBOMe?
  • 25B-NBOMe is a synthetic hallucinogenic substance belonging to the NBOMe family. It is chemically related to the phenethylamine 2C-B and is known for its hallucinogenic properties.
  • How is 25B-NBOMe typically consumed?
  • 25B-NBOMe is often taken sublingually (under the tongue), where it can be absorbed into the bloodstream. It is essential to note that it is not active when ingested orally.
  • What are the effects of 25B-NBOMe?
  • 25B-NBOMe is known for inducing hallucinations and altering perception. Users have reported visual distortions, changes in thought processes, and sometimes intense emotional experiences. These effects can be unpredictable and vary between individuals.
  • What are the risks associated with 25B-NBOMe?
  • 25B-NBOMe is associated with potentially severe risks, including life-threatening toxicity and fatalities. Some individuals have experienced autonomic dysfunction, sympathomimetic toxicity (vasoconstriction, hypertension, tachycardia), and even seizures.
  • Is 25B-NBOMe legal?
  • The legal status of 25B-NBOMe varies by country. It is classified as a controlled substance in many places, and its possession, distribution, or use may be illegal.
  • What distinguishes 25B-NBOMe from other hallucinogenic substances?
  • 25B-NBOMe is chemically distinct from other hallucinogens and is known for causing numbing of the tongue and mouth when taken sublingually. This characteristic taste and sensation can help differentiate it from other substances like LSD.
  • Can 25B-NBOMe be confused with other drugs?
  • Yes, 25B-NBOMe is sometimes misrepresented as LSD. Blotter papers containing 25B-NBOMe can have a bitter taste, unlike the typically tasteless or slightly metallic taste of LSD.
  • Are there any long-term effects of 25B-NBOMe use?
  • Due to limited documentation, the long-term effects of 25B-NBOMe use need to be better understood. Research on this topic is ongoing.
  • Is there emergency treatment available for 25B-NBOMe intoxication?
  • Currently, there are no specific antidotes for 25B-NBOMe. Acute intoxication is managed through symptomatic treatments, which may include benzodiazepines, antipsychotic medications, and antiarrhythmic agents.
  • Is 25B-NBOMe still available on the market?
  • The availability of 25B-NBOMe may vary by location and over time. However, it is important to note that its use may be illegal in many jurisdictions due to safety concerns. It is strongly discouraged to use unregulated substances.


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