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Psychedex
Facts label

Dextromethorphan Facts

Dissociative; Substituted morphinan; NMDA receptor antagonist

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 75 mgLight100 – 200 mgCommon200 – 400 mgStrong400 – 700 mgHeavy700+ mg

Starts in 30 – 120 minLasts 8 – 12 hoursAfter-effects 4 – 24 hours

Body and dependence

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

Tolerance

Builds
Moderate
Fully resets after
10 days
Carries over to
ketamine; PCP; nitrous oxide; memantine

Effectslikely at a common dose

Perception
none likely · 30 possible, including Spatial disorientation, Vestibular distortion, Visual acuity suppression
Body
Motor control impairment; +27 possible, including Nystagmus (eye wobbles), Dizziness, Nausea
Thinking
Cognitive impairment; Decision impairment; +25 possible, including Analysis suppression, Confusion, Memory suppression
Feeling
none likely · 7 possible, including Anxiety, Emotional lability
Self
none likely · 8 possible, including Derealization, Depersonalization, Communication suppression
Time
none likely · 4 possible, including Temporal disorientation
Awareness
none likely · 3 possible

Who shouldn't take it

Absolute
MAOI use
Relative
Respiratory compromise; Serotonergic medication use; Psychotic disorders; Hepatic impairment; CYP2D6 poor metabolizer status; Pregnancy and breastfeeding

Combinations64 recorded

Lethal (8)
Benzodiazepines, Barbiturates; GHB, Baclofen; GHB, GBL; Local anesthetics; MDMA; PCP; Tramadol; αMT
Dangerous (39)
Alpha-2 adrenergic receptor antagonist; Amphetamines; Antihistamines; Benzodiazepines; Buprenorphine, Kratom; Cannabis, THC; Gabapentin, Pregabalin; MAOIs; MDMA, Amphetamines; Naltrexone; NRIs; NSAIDs; Stimulants; THC; 5-HTP, Tryptophan; Anticholinergics; Antipsychotics; Atypical antipsychotics; Buspirone; Caffeine; CBD; Clonidine, Guanfacine; Dopamine agonists; DXM; and 15 more, see full page
Caution (14)
See full page: psychedex.org/substances/dextromethorphan
Not graded (3)
Not listed never means safe.

Seek help immediately if

  • Severe disorientation; unable to move or speak (deep dissociation / "k-hole")
  • Complete loss of coordination — cannot stand or walk safely
  • Vomiting while incapacitated (choking / aspiration risk)
  • Very high blood pressure; fast heart rate
  • Slow or shallow breathing at high doses (especially mixed with depressants)
  • Unconsciousness; rarely, seizures

What to do

  1. Move them somewhere safe, away from stairs, water, roads, and sharp edges — they cannot protect themselves
  2. Place in the recovery position if vomiting or unconscious (aspiration is a key risk)
  3. Stay with them and reassure calmly; keep the environment quiet
  4. If breathing is slow/shallow or they are unresponsive, call emergency services
  5. Do not let them wander; do not leave them alone
  6. Be ready to give rescue breaths / CPR

Effects wear off with time in a safe, monitored setting. The main dangers are physical injury and aspiration while incapacitated, and respiratory depression when combined with other depressants — not the dissociation itself.

988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE

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