25I-NBF is approximately 6-8 times less potent than 25I-NBOMe but shares a similar qualitative effect profile and comparable safety concerns. Primary activity occurs through potent partial agonism at 5-HT2A and 5-HT2C receptors with bias toward β-arrestin 2 signaling; peripheral α-adrenergic activity contributes to vasoconstriction and cardiovascular strain. Oral bioavailability is low; sublingual, buccal, or insufflated administration is typically used. Marked vasoconstriction, tachycardia, and hypertension have been reported at doses of 8 mg and above. Fatal intoxications with closely related NBOMe compounds have occurred, often involving polydrug combinations with stimulants or MAOIs.
Also known as: 2c-i-nbf, Nbf-2c-i, Cimbi-21, 2-fluorophenyl, 4-iodo-2,5-dimethoxyphenyl
Classification
Chemical: Phenethylamine
Psychoactive: Psychedelic
Psychoactive: Stimulant
Tag: Hallucinogen
Tag: Research-Chemical
Tag: Tentative
Effects
Stimulation
Increased Heart Rate
Vasoconstriction
Jaw Tension
Restlessness
Numbness
Time Distortion
Euphoria
Empathy
Anxiety
Confusion
Thought Loop
Visual Patterning
Color Enhancement
Closedeye Visuals
Bodily Control Enhancement
Tactile Enhancement
Open Eye Visuals
Routes of Administration
Sublingual
Dosage
Threshold: 1 – 2 mg
Light: 2 – 4 mg
Common: 4 – 8 mg
Strong: 8 – 12 mg
Heavy: 12 mg +
Duration
Onset: 0.17-0.5 h
Comeup: 0.5-1 h
Peak: 2-4 h
Offset: 2-4 h
After Effects: 8-18 h
Total Duration: 6-10 h
Insufflated
Dosage
Threshold: 0.5 mg
Light: 1 – 2 mg
Common: 2 – 5 mg
Strong: 5 – 8 mg
Heavy: 8 mg +
Duration
Onset: 0.08-0.25 h
Comeup: 0.33-0.75 h
Peak: 2-4 h
Offset: 2-4 h
After Effects: 6-16 h
Total Duration: 5-9 h
Oral
Dosage
Threshold: 4 mg
Light: 6 – 10 mg
Common: 10 – 16 mg
Strong: 16 – 22 mg
Heavy: 22 mg +
Duration
Onset: 0.5-1 h
Comeup: 0.75-1.5 h
Peak: 2-4 h
Offset: 2-4 h
After Effects: 8-18 h
Total Duration: 6-10 h
Harm Reduction
Check interactions before mixing substances, pay attention to dose spacing and hydration, and treat all dosage guidance as approximate rather than guaranteed safe.
Sources
Substance data is aggregated from the following public harm-reduction and reference sources.
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25I-NBF - DrugsPRO efnisleiðsögn
25I-NBF: 25I-NBF is approximately 6-8 times less potent than 25I-NBOMe but shares a similar qualitative effect profile and comparable safety concerns. Primary activity occurs through potent partial agonism at 5-HT2A and 5-HT2C receptors with bias toward β-arrestin 2 signaling; peripheral α-adrenergi
