25I-NBF (2C-I-NBF, NBF-2C-I, Cimbi-21) is a compound derived from the phenethylamine hallucinogen 2C-I. It exhibits potent partial agonism for the human 5-HT2A receptor, known for its involvement in various neurological processes. Notably, it isn’t very objective towards the β-arrestin 2 coupled signalling pathway, indicating its complex interaction within the receptor system. In research, its 11C radiolabeled form has been explored as a potential ligand for mapping the distribution of 5-HT2A receptors in the brain, primarily utilizing positron emission tomography (PET).

IUPAC name
CAS Number919797-21-0 
PubChem CID57469209
CompTox Dashboard (EPA)DTXSID00726753
Chemical and physical data
Molar mass415.247 g·mol−1


In Hungary, Japan, Latvia, and Vermont, the possession and use of 25I-NBF are prohibited by law.
In Sweden, the Riksdag classified 25I-NBF under Swedish schedule I (“substances, plant materials, and fungi which normally do not have medical use”) as of January 26, 2016. The classification was published by the Medical Products Agency (MPA) in regulation HSLF-FS 2015:35, with the compound listed as 25I-NBF and 2-(4-jodo-2,5-dimetoxifenyl)-N-(2-fluorophenyl)etanamin.
Similarly, 25I-NBF is categorized as a Class A drug in the United Kingdom according to the N-benzyl phenethylamine catch-all clause in the Misuse of Drugs Act 1971.


  1. What is 25I-NBF?
    25I-NBF is a synthetic hallucinogenic compound and a derivative of the phenethylamine 2C-I. It is known for its psychedelic effects and is part of the NBOMe family of drugs.
  2. How is 25I-NBF used?
    25I-NBF is typically consumed orally, but it can also be taken sublingually or through other routes of administration. It is often found in the form of blotters, powders, or liquid solutions.
  3. What are the effects of 25I-NBF?
    The effects of 25I-NBF include visual and sensory distortions, changes in mood, altered perception of time, and intensified sensory experiences. Users may also experience shifts in thought patterns and heightened emotional states.
  4. Are there any risks associated with 25I-NBF use?
    Yes, 25I-NBF is known to have significant health risks. It can lead to adverse reactions such as increased heart rate, elevated blood pressure, and potential psychological distress. Overdosing on 25I-NBF can result in severe complications, including life-threatening situations.
  5. Is 25I-NBF legal?
    The legal status of 25I-NBF varies by country and region. It is often classified as a controlled substance due to its hallucinogenic properties and associated risks. Always check the specific regulations in your area.
  6. Is 25I-NBF addictive?
    There is limited research on the addictive potential of 25I-NBF. However, substances with hallucinogenic properties are generally not associated with physical dependence. Psychological dependence can still occur in some cases.
  7. Are there any medical uses for 25I-NBF?
    No, 25I-NBF is not approved for any medical purposes. It is primarily used for recreational or research purposes, but its use is strongly discouraged due to its potential dangers.
  8. What should I do if I or someone I know experiences adverse effects from 25I-NBF?
    If you or someone experiences negative effects or overdoses on 25I-NBF, seek immediate medical assistance. Call emergency services for help and follow their instructions. Do not delay in seeking professional medical care in such situations.
  9. How can one minimize the risks associated with 25I-NBF use?
    The best way to minimize the risks associated with 25I-NBF is to avoid its use entirely. Education about the potential dangers and harm reduction practices can also help individuals make informed decisions and take necessary precautions.
  10. What are the long-term effects of 25I-NBF use?

Research on the long-term effects of 25I-NBF is limited. However, the potential risks of continued use may include persistent psychological distress, changes in cognitive function, and other adverse health outcomes. It is crucial to prioritize personal well-being and safety when considering substance use.


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  7. “A Magyarországon megjelent, a Kábítószer és Kábítószer-függőség Európai Megfigyelő Központjának Korai Jelzőrendszerébe (EMCDDA EWS) 2005 óta bejelentett ellenőrzött anyagok büntetőjogi vonatkozású besorolása” [Criminal classification of controlled substances published in Hungary and notified to the European Monitoring Center for Drugs and Drug Addiction (EMCDDA EWS) since 2005] (PDF) (in Hungarian).
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