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Psychedex
Facts label

4-FMA Facts

Stimulant; Substituted amphetamine; Monoamine releasing agent

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 10 mgLight25 – 50 mgCommon50 – 75 mgStrong100 – 125 mgHeavy125+ mg

Starts in 20 – 40 minLasts 4 – 8 hoursAfter-effects 3 – 12 hours

Body and dependence

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

Tolerance

Builds
Moderate
Fully resets after
10.5 days
Carries over to
amphetamine; methamphetamine; cocaine; MDMA; other dopaminergic stimulants

Effectslikely at a common dose

Perception
none likely · 8 possible
Body
Appetite suppression; Dry mouth; Pupil dilation; Stimulation; Wakefulness; +24 possible, including Dehydration sensation, Heart rate perception changes, Insomnia
Thinking
Cognitive euphoria; Thought acceleration; +20 possible, including Compulsive redosing urge, Suggestibility enhancement
Feeling
Euphoria; +9 possible, including Anhedonia, Anxiety, Depression
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
Concurrent MAOI use; Concurrent tramadol use
Relative
Pre-existing cardiovascular or cerebrovascular disease; Pre-existing hypertension; Seizure disorder; Hepatic impairment; CYP2D6 poor metabolizer phenotype; Concurrent CYP2D6 or CYP3A4 inhibitors; Pregnancy; Concurrent serotonergic medications

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-fma
Not graded (3)
Not listed never means safe.

Seek help immediately if

  • Chest pain; racing, pounding, or irregular heartbeat
  • Very high body temperature; heavy sweating; hot, flushed skin
  • Severe agitation, paranoia, panic, or confusion
  • Severe headache; muscle rigidity or twitching
  • Seizures
  • Signs of stroke — face drooping, one-sided weakness, slurred speech
  • Difficulty breathing; collapse or unconsciousness

What to do

  1. Call emergency services for chest pain, overheating, seizure, or unresponsiveness
  2. Move them to a cool, quiet place and reduce stimulation
  3. Cool the body — remove excess clothing, apply cool damp cloths, fan them
  4. Keep them calm; reassure — panic worsens the cardiovascular strain
  5. If seizing, protect from injury (don't restrain); recovery position afterward
  6. Monitor breathing and be ready to give rescue breaths / CPR

Most stimulant overdoses settle with cooling, a calm environment, and time. The medical danger is hyperthermia, cardiac events (arrhythmia, heart attack, stroke), and seizures — get help immediately if any appear.

988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE

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