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25I-NBF Stats & Data

Psychedelic Stimulant Research-chemical

2c-i-nbf Nbf-2c-i Cimbi-21

NPS DataHub

MW415.25

FormulaC17H19FINO2

CAS919797-21-0

IUPACN-[(2-fluorophenyl)methyl]-2-(4-iodo-2,5-dimethoxyphenyl)ethanamine

SMILESCOc1cc(CCNCc2ccccc2F)c(OC)cc1I

InChIKeyLPBKNBHMWRBPHT-UHFFFAOYSA-N

Phenethylamines; Cathinones; 2020/1. Von 2-Phenethylamin abgeleitete Verbindungen; 2021/1. Von 2-Phenethylamin abgeleitete Verbindungen; 2022/1. Von 2-Phenethylamin abgeleitete Verbindungen

Chemical Class Phenethylamine

Psychoactive Class Psychedelic / Stimulant

Half-Life Human plasma half-life not published; animal models suggest 2 – 3 h, but active metabolites/prolonged receptor occupancy extend subjective effects.

Receptor Profile

Receptor Actions

Agonists

5-HT2A receptor agonist (partial, potent)

5-HT2B receptor agonist (cardiotoxic)

Other

β-arrestin 2 signaling pathway bias

History & Culture

25I-NBF emerged as part of the broader NBOMe and NBF series of N-benzyl phenethylamine derivatives developed for research purposes. The compound has been investigated in its carbon-11 radiolabelled form (designated Cimbi-21) as a potential ligand for positron emission tomography (PET) imaging, specifically for mapping the distribution of 5-HT2A serotonin receptors in the brain. Prior to its scheduling in various jurisdictions, 25I-NBF was briefly available commercially in limited markets as a novel psychoactive substance. However, its period of availability was relatively short before regulatory action was taken across multiple countries.

Effect Profile

Curated

Psychedelic 6.2

Strong visuals with moderate headspace and body load, mild auditory effects

Visual Intensity×3

Headspace Depth×3

Auditory Effects×1

Body Load / Somatic Effects×1

Stimulant 3.1

Strong anxiety/jitters with moderate euphoria, low stimulation and focus

Stimulation / Energy×3

Euphoria / Mood Lift×2

Focus / Productivity×2

Anxiety / Jitters×1

Based on reports from:

Erowid Experience Reports PsychonautWiki 25I-NBF

Tolerance & Pharmacokinetics

drugs.wiki

Half-Life

Human plasma half-life not published; animal models suggest 2 – 3 h, but active metabolites/prolonged receptor occupancy extend subjective effects.

Addiction Potential

No evidence for physical dependence. Psychological habit-forming potential is low to moderate; tolerance builds quickly after single use.

Tolerance Decay

Full tolerance 1d Half tolerance 7d Baseline ~14d

Rapid tolerance build similar to NBOMe/LSD is reported anecdotally; noticeable tolerance persists several days and may take 1–2 weeks to normalize.

Cross-Tolerances

LSD/psilocybin/2C-series/NBOMe-series

60% ●○○

Legal Status

Country	Status	Notes
Hungary	Illegal	Classified as a prohibited substance under national drug legislation.
Japan	Illegal	Controlled as a designated substance under Japanese drug control laws.
Latvia	Illegal	Prohibited under national controlled substances legislation.
Sweden	Schedule I	Added to the Narcotic Drugs Punishments Act on January 26, 2016. Listed under Swedish Schedule I as a substance without accepted medical use, published by the Medical Products Agency in regulation HSLF-FS 2015:35.
United Kingdom	Class A	Controlled under the Misuse of Drugs Act 1971 via the N-benzylphenethylamine catch-all clause. Class A substances carry the most severe penalties, including up to 7 years imprisonment for possession.
United States	State-level scheduling (Vermont)	Not federally scheduled at the national level. The state of Vermont has independently classified 25I-NBF as an illegal substance. Federal prosecution may still be possible under the Federal Analogue Act when sold for human consumption.

Harm Reduction

drugs.wiki

• 25I-NBF appears several-fold less potent than 25I-NBOMe yet retains broadly similar qualitative effects; mg-level errors can still be medically serious. Use a 0.001 g scale only to prepare a liquid for volumetric dosing; do not eyeball powders.

• NBOMe/NBxx compounds have caused severe toxicity and deaths at what some considered “recreational” doses; risk is heightened by uneven dosing, intranasal powder use, and stimulant/MAOI combinations.

• Misrepresentation on blotter is documented: NBOMe-class drugs have been sold as LSD. Use reagents (Ehrlich or Hofmann positive suggests an indole like LSD; NBOMes typically do not react with Ehrlich) and prefer trusted drug checking. A bitter/metallic taste and oral numbness can accompany NBOMe/NBxx tabs.

• Strong vasoconstriction, tachycardia and hypertension are the main acute physical risks; cold, pale/numb extremities, chest pain, or severe headache warrant immediate medical care. Avoid other vasoconstrictors (nicotine, decongestants, stimulants).

• Insufflation increases adverse events and local tissue irritation; if used intranasally, a dilute measured solution is safer than powder to reduce hot-spots. Buccal/sublingual routes are generally preferred.

• Oral activity across NBOMe/NBxx varies; do not assume that swallowing a blotter eliminates effects or risk.

• Start with an allergy test (≤ 0.5 mg buccal) on first exposure; wait a full day before any reassessment due to variability and slow-onset outliers.

• Strongly avoid poly-drug use, especially serotonergic agents (MAOIs, tramadol, DXM, triptans) and stimulants (amphetamines, MDMA, cocaine). These combinations increase risks of hypertension, seizures, and serotonin toxicity.

• Temperature dysregulation and overexertion have been noted with NBOMe-class drugs; take breaks, keep cool, sip fluids, and avoid redosing during the peak.

• Mental effects depend heavily on set and setting; anxious or chaotic environments increase the risk of panic or unsafe behavior. Trip sitter and a calm space are recommended.

• Post-acute stimulation/insomnia is common; avoid using depressants like large alcohol doses or non-prescribed benzodiazepines to force sleep due to interaction risks.