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Psychedex
Facts label

βk-2C-B Facts

Psychedelic; Entactogen; Substituted cathinone; Serotonin 2A receptor agonist

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 50 mgLight60 – 80 mgCommon80 – 100 mgStrong100 – 150 mgHeavy150+ mg

Starts in 20 – 70 minLasts 8 – 12 hoursAfter-effects 2 – 6 hours

Body and dependence

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

Tolerance

Builds
Rapid
Fully resets after
7 days
Carries over to
LSD; psilocybin; mescaline; DOx series; 2C-x series

Effectslikely at a common dose

Perception
Color alteration; Color enhancement; +26 possible, including Visual haze / noise, Spatial disorientation
Body
Pupil dilation; Stimulation; Wakefulness; +20 possible, including Heart rate perception changes, Excessive sweating, Vasoconstriction
Thinking
none likely · 26 possible, including Memory suppression, Thought loops, Suggestibility enhancement
Feeling
none likely · 9 possible, including Emotional lability, Anxiety, Paranoia
Self
none likely · 7 possible, including Derealization
Time
none likely · 3 possible, including Temporal disorientation
Transpersonal
none likely · 1 possible
Awareness
none likely · 1 possible

Who shouldn't take it

Absolute
Cardiovascular disease; Personal or family history of psychotic disorders; Concurrent MAOI use
Relative
Seizure disorders; Hepatic impairment; CYP2D6 poor metabolizer phenotype; Pregnancy and lactation; Concurrent serotonergic medication

Combinations60 recorded

Lethal (1)
MAOIs
Dangerous (29)
Amphetamines; Ephedrine, Pseudoephedrine; Local anesthetics; MDMA, MDA; NRIs; Stimulants; Alpha-2 adrenergic receptor antagonist; Anticholinergics; Antipsychotics; Buspirone; Caffeine; Clonidine, Guanfacine; Dopamine agonists; GHB, Baclofen; GHB, GBL; Ibogaine; Ketamine, DXM, PCP; Lithium; MDMA, Amphetamines; NSAIDs; Opioids; Poppers (Alkyl nitrites); Poppers, Nitrates; Psychedelics; and 5 more, see full page
Caution (27)
See full page: psychedex.org/substances/bk-2c-b
Not graded (3)
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

psychedex.org/substances/bk-2c-b · Version r1.a1 · Not medical adviceValues as of
On the printout