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25B-NBOMe Facts

Psychedelic; Substituted phenethylamine; Serotonin 2A receptor agonist

Description

25B-NBOMe — N-Bomb, Smiles — is a synthetic psychedelic of the phenethylamine class. It activates serotonin receptors in the brain, producing the visual distortions and cognitive shifts characteristic of classical psychedelics.[1]

Subjective effects include geometric visual patterns, color enhancement, thought acceleration, emotional lability, and intense physical stimulation. The experience is more bodily aggressive than most classical psychedelics — potent psychedelic perceptual shifts collide with a heavy cardiovascular load that feels physically punishing.

No physical dependence has been documented, but 25B-NBOMe carries critical acute toxicity — fatal blood concentrations overlap with non-fatal ones, leaving no safe threshold definable.[2][3][4] It also activates adrenergic receptors, constricting blood vessels and producing cardiac arrhythmia risk not seen with classical psychedelics.[1]

Dose and durationby route · individual sensitivity varies

Sublingual(µg)
Threshold< 50 µgLight100 – 250 µgCommon250 – 500 µgStrong500 – 750 µgHeavy750+ µg

Starts in 15 – 30 minLasts 8 – 12 hoursAfter-effects 4 – 12 hours

Body and dependence

Acute toxicity
Critical
Chronic toxicity
Moderate
Physical dependence
None
Psychological dependence
Low
Withdrawal
None recorded
Compulsive redosing
Negligible

Tolerance

Builds
Rapid
Fully resets after
14 days
Carries over to
LSD; psilocybin; mescaline; DMT; 25I-NBOMe; 25C-NBOMe; 2C-B

Effectslikely at a common dose

Perception
Color enhancement; Visual drifting; Color alteration; Symmetrical texture repetition; Environmental patterning; Geometry; Visual breathing; +26 possible, including Spatial disorientation, Visual haze / noise, Double vision
Body
Stimulation; Vasoconstriction; Pupil dilation; Wakefulness; Body scan awareness; +30 possible, including Insomnia, Muscle tension, Abnormal heartbeat
Thinking
Novelty enhancement; +31 possible, including Cognitive impairment, Memory suppression, Cognitive dysphoria
Feeling
none likely · 10 possible, including Emotional lability, Anxiety, Dysphoria
Self
none likely · 10 possible, including Derealization, Depersonalization, Communication suppression
Time
Time alteration; +3 possible, including Temporal disorientation
Transpersonal
none likely · 1 possible
Awareness
none likely · 3 possible

Who shouldn't take it

Absolute
Cardiac arrhythmias; Long QT syndrome; Uncontrolled hypertension; Coronary artery disease; Epilepsy; Psychotic disorders; Pregnancy and breastfeeding
Relative
Bipolar disorder; Hepatic impairment; Renal impairment

Combinations61 recorded

Lethal (1)
MAOIs
Dangerous (18)
MDMA, MDA; NRIs; Buspirone; Dopamine agonists; GHB, Baclofen; GHB, GBL; Ibogaine; Ketamine, DXM, PCP; Lithium; Local anesthetics; MDMA, Amphetamines; NDRIs (Wellbutrin); Psychedelics; Salvia, Ibogaine; SNRIs; SSRIs; Stimulants; Synthetic cannabinoids
Caution (37)
See full page: psychedex.org/substances/25b-nbome
Not graded (5)
Not listed never means safe.

Seek help immediately if

Most difficulty is psychological (intense fear, panic, confusion) and passes with calm support — the signs below mean seek emergency help:

  • Very high body temperature; hot, dry skin
  • Seizures
  • Chest pain; fast or irregular heartbeat
  • Severe muscle rigidity, tremor, or twitching (possible serotonin syndrome)
  • Cold, pale, or blue fingers/toes — severe vasoconstriction (notably NBOMe / DOx)
  • Persistent vomiting; unconsciousness; uncontrollable agitation or risk of self-harm

What to do

  1. Stay calm and reassure — remind them they took a drug and the effect will pass
  2. Move to a calm, quiet, safe space with low light; reduce noise and sensory input
  3. Keep them from harm — they may act on fear or confusion; stay with them, don't leave them alone
  4. Talk them down gently; don't grab or restrain unless they're in danger
  5. For the medical signs above (overheating, seizure, chest pain, vasoconstriction, unresponsive) call emergency services
  6. If overheating, cool the body; be ready to give rescue breaths / CPR

The experience is time-limited and usually resolves with calm reassurance in a safe setting — psychological first aid, not medication. Serious physical harm is uncommon for classic psychedelics (LSD, psilocybin) but real for some potent phenethylamines (NBOMe, DOx), where hyperthermia, seizures, and vasoconstriction warrant emergency care.

988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE

Version r1 · Not medical advice

References

  1. [1]
    ^abRickli A, Luethi D, Reinisch J, Buchy D, Hoener MC, Liechti ME (2015) Receptor interaction profiles of novel N-2-methoxybenzyl (NBOMe) derivatives of 2,5-dimethoxy-substituted phenethylamines (2C drugs) — Neuropharmacology doi:10.1016/j.neuropharm.2015.08.034
  2. [2]
    ^Shanks KG, Sozio T, Behonick GS (2015) Fatal Intoxications with 25B-NBOMe and 25I-NBOMe in Indiana During 2014. — Journal of Analytical Toxicology doi:10.1093/jat/bkv058
  3. [3]
    ^Al-Imam A (2018) 25b-NBOMe: A Case Report of Sudden Death and Insightful View of Google Trends Data. — Iranian Journal of Psychiatry and Behavioral Sciences doi:10.5812/ijpbs.9870
  4. [4]
    ^Gee P, Schep LJ, Jensen BP, Moore G, Barrington S (2016) Case series: toxicity from 25B-NBOMe--a cluster of N-bomb cases. — Clinical Toxicology doi:10.3109/15563650.2015.1115056
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