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Psychedex
Facts label

Phentermine Facts

Stimulant; Substituted amphetamine; Norepinephrine releasing agent

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 8 mgLight8 – 15 mgCommon15 – 37.5 mgStrong37.5 – 37.5 mgHeavynot recorded

Starts in 30 – 60 minLasts 8 – 14 hoursAfter-effects 12 – 24 hours

Body and dependence

Acute toxicity
Moderate
Chronic toxicity
Moderate
Physical dependence
Negligible
Psychological dependence
Low
Withdrawal
None recorded
Compulsive redosing
Low

Tolerance

Builds
Rapid
Fully resets after
Not recorded
Carries over to
amphetamine; methamphetamine; MDMA

Effectslikely at a common dose

Perception
none likely · 1 possible
Body
Appetite suppression; Stimulation; Vasoconstriction; Wakefulness; +14 possible, including Abnormal heartbeat, Insomnia, Heart rate perception changes
Thinking
none likely · 4 possible
Feeling
none likely · 3 possible, including Anxiety
Self
none likely · 4 possible, including Craving
Awareness
Sustained attention (vicara); +1 possible

Who shouldn't take it

Absolute
Cardiovascular disease; Agitated states; History of drug abuse; Hyperthyroidism; Sympathomimetic amine hypersensitivity; Pregnancy; Lactation; MAOI use (within 14 days); Glaucoma

Combinations60 recorded

Lethal (1)
MAOIs
Dangerous (28)
Alpha-2 adrenergic receptor antagonist; Anticholinergics; Caffeine; Ephedrine, Pseudoephedrine; GHB, Baclofen; Local anesthetics; MDMA, Amphetamines; MDMA, MDA; NDRIs (Wellbutrin); NRIs; Opioids; SNRIs; SSRIs; Stimulants; 5-HTP, Tryptophan; Antipsychotics; Buspirone; Dopamine agonists; DXM; GHB, GBL; Ibogaine; Ketamine, DXM, PCP; Lithium; NSAIDs; and 4 more, see full page
Caution (28)
See full page: psychedex.org/substances/phentermine
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/phentermine · Version r1 · Not medical adviceValues as of
On the printout