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Psychedex
Facts label

Fenethylline Facts

Stimulant; Substituted amphetamine; Adenosine receptor antagonist

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 10 mgLight20 – 40 mgCommon40 – 100 mgStrong100 – 200 mgHeavy200+ mg

Starts in 90 – 120 minLasts 3 – 4 hoursAfter-effects 2 – 6 hours

Body and dependence

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

Tolerance

Builds
Moderate
Fully resets after
14 days
Carries over to
amphetamine; methamphetamine; other amphetamine-type stimulants

Effectslikely at a common dose

Perception
none likely · 2 possible
Body
Appetite suppression; Stimulation; Wakefulness; +20 possible, including Heart rate perception changes, Insomnia, Vasoconstriction
Thinking
none likely · 14 possible, including Compulsive redosing urge
Feeling
none likely · 8 possible, including Anxiety, Anhedonia, Depression
Self
none likely · 7 possible, including Craving, Ego inflation
Time
none likely · 1 possible
Awareness
none likely · 1 possible

Who shouldn't take it

Absolute
Known Brugada syndrome; Recent myocardial infarction or unstable angina; MAOI use (current or within 14 days)
Relative
Cardiac conduction abnormalities or prolonged QT interval; Coronary artery disease; Psychotic disorders or family history of schizophrenia; Hepatic impairment affecting CYP2D6 or CYP1A2; Pregnancy and lactation; Concurrent CYP2D6-metabolized drugs with narrow therapeutic index

Combinations62 recorded

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