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Psychedex
Facts label

4-FA Facts

Stimulant; Entactogen; Substituted amphetamine; Monoamine releasing agent

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 25 mgLight25 – 75 mgCommon75 – 130 mgStrong130 – 150 mgHeavy150+ mg

Starts in 45 – 75 minLasts 5 – 8 hoursAfter-effects 6 – 12 hours

Body and dependence

Acute toxicity
High
Chronic toxicity
Moderate
Physical dependence
Low
Psychological dependence
Moderate
Withdrawal
Mild
Compulsive redosing
Moderate

Tolerance

Builds
Moderate
Fully resets after
10 days
Carries over to
amphetamine; methamphetamine; MDMA; methylphenidate

Effectslikely at a common dose

Perception
none likely · 10 possible
Body
Dry mouth; Pupil dilation; Appetite suppression; Stimulation; Insomnia; Wakefulness; +25 possible, including Dehydration sensation, Heart rate perception changes, Vasoconstriction
Thinking
Cognitive euphoria; Thought acceleration; +24 possible, including Cognitive dysphoria, Compulsive redosing urge, Thought disorganization
Feeling
Euphoria; +12 possible, including Anxiety, Depression, Anhedonia
Self
none likely · 9 possible, including Craving, Ego inflation
Time
none likely · 2 possible
Awareness
none likely · 2 possible

Who shouldn't take it

Absolute
Cardiovascular disease; Uncontrolled hypertension; Pregnancy; Concurrent MAOI use
Relative
Psychotic disorders; Concurrent serotonergic drug use; Concurrent antiretroviral therapy (CYP2D6 inhibitors)

Combinations61 recorded

Lethal (2)
MAOIs; Tramadol
Dangerous (33)
Alpha-2 adrenergic receptor antagonist; Anticholinergics; Atypical antipsychotics; Caffeine; Dopamine agonists; Ephedrine, Pseudoephedrine; Local anesthetics; MDMA, Amphetamines; MDMA, MDA; NDRIs (Wellbutrin); NRIs; Opioids; SNRIs; SSRIs; Stimulants; 5-HTP, Tryptophan; Antihistamines; Antipsychotics; Buspirone; Clonidine, Guanfacine; DXM; GHB, Baclofen; GHB, GBL; Ibogaine; and 9 more, see full page
Caution (23)
See full page: psychedex.org/substances/4-fa
Not graded (3)
Not listed never means safe.

Seek help immediately if

  • Overheating / very high body temperature — heavy sweating, then hot dry skin (the leading cause of MDMA deaths, worse when dancing in hot venues)
  • Muscle rigidity, jaw clenching, tremor, or twitching (possible serotonin syndrome)
  • Fast, pounding heartbeat; chest pain
  • Agitation, confusion; seizures
  • Hyponatremia (water intoxication) — headache, confusion, drowsiness, vomiting, and seizures from drinking too much water
  • Nausea/vomiting; collapse or unconsciousness

What to do

  1. Move them somewhere cool and help them cool down — overheating is the main danger
  2. Sip water to stay hydrated but DO NOT overdrink — roughly a cup (250 ml) per hour if active; too much water can be deadly (hyponatremia)
  3. Get them to rest and stop dancing
  4. For overheating, seizures, chest pain, muscle rigidity/tremor, confusion, or unresponsiveness, call emergency services
  5. Recovery position if drowsy or vomiting; stay with them
  6. Be ready to give rescue breaths / CPR

Most resolve with cooling, rest, sensible hydration, and time. The life-threatening dangers are hyperthermia, serotonin syndrome, and hyponatremia (too much water) — each a medical emergency, not something to wait out.

988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE

psychedex.org/substances/4-fa · Version r1.a1 · Not medical adviceValues as of
On the printout