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Psychedex
Facts label

Methylnaphthidate Facts

Stimulant; Phenidate; Dopamine reuptake inhibitor

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 4 mgLight10 – 15 mgCommon15 – 30 mgStrong30 – 50 mgHeavy50+ mg

Starts in 1 – 10 minLasts 2 – 5 hoursAfter-effects 1 – 8 hours

Also recorded: Insufflated. See full page: psychedex.org/substances/methylnaphthidate

Body and dependence

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

Tolerance

Builds
Moderate
Fully resets after
10 days
Carries over to
methylphenidate; ethylphenidate; isopropylphenidate; cocaine

Effectslikely at a common dose

Perception
none likely · 6 possible
Body
Appetite suppression; Pupil dilation; Stimulation; Wakefulness; +18 possible, including Insomnia, Vasoconstriction, Muscle tension
Thinking
none likely · 19 possible, including Compulsive redosing urge, Cognitive dysphoria
Feeling
none likely · 7 possible, including Anxiety, Anhedonia, Depression
Self
none likely · 7 possible, including Craving, Ego inflation
Time
none likely · 2 possible
Awareness
Sustained attention (vicara); +2 possible

Who shouldn't take it

Absolute
Pre-existing cardiovascular disease; MAOI use
Relative
Seizure disorders; History of psychosis or bipolar disorder; Concurrent serotonergic medication (SSRIs, SNRIs, triptans)

Combinations64 recorded

Lethal (4)
Cocaine; Ibogaine; MDMA; 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/methylnaphthidate
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/methylnaphthidate · Version r1.a1 · Not medical adviceValues as of
On the printout