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Psychedex
Facts label

4F-MPH Facts

Stimulant; Phenidate; Dopamine reuptake inhibitor

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 5 mgLight5 – 10 mgCommon10 – 15 mgStrong15 – 20 mgHeavy20+ mg

Starts in 30 – 60 minLasts 4 – 8 hoursAfter-effects 5 – 10 hours

Also recorded: Insufflated. See full page: psychedex.org/substances/4f-mph

Body and dependence

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

Tolerance

Builds
Moderate
Fully resets after
5 days
Carries over to
methylphenidate; ethylphenidate; isopropylphenidate; other phenidate analogs

Effectslikely at a common dose

Perception
none likely · 3 possible
Body
Wakefulness; Appetite suppression; Stimulation; +18 possible, including Insomnia, Vasoconstriction, Heart rate perception changes
Thinking
none likely · 15 possible, including Compulsive redosing urge
Feeling
none likely · 9 possible, including Anxiety, Anhedonia, Dysphoria
Self
none likely · 7 possible, including Craving, Ego inflation
Time
none likely · 2 possible
Awareness
none likely · 1 possible

Who shouldn't take it

Absolute
Severe cardiovascular disease; Concurrent MAOI use; Pheochromocytoma
Relative
Hypertension; Seizure disorders; Anxiety disorders; History of psychosis or bipolar disorder; Hepatic impairment; Pregnancy and lactation

Combinations62 recorded

Lethal (2)
Ibogaine; Tramadol
Dangerous (29)
Alpha-2 adrenergic receptor antagonist; Amphetamines; Benzodiazepines, Barbiturates; Ephedrine, Pseudoephedrine; Local anesthetics; MAOIs; MDMA, Amphetamines; MDMA, MDA; NDRIs (Wellbutrin); NRIs; Opioids; SSRIs; Stimulants; Anticholinergics; Antipsychotics; Buspirone; Caffeine; Dopamine agonists; DXM; GHB, Baclofen; GHB, GBL; Ketamine, DXM, PCP; Lithium; NSAIDs; and 5 more, see full page
Caution (28)
See full page: psychedex.org/substances/4f-mph
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/4f-mph · Version r1 · Not medical adviceValues as of
On the printout