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Psychedex
Facts label

1Fe-LSD Facts

Psychedelic; Lysergamide; Serotonin 2A receptor agonist

Dose and durationby route · individual sensitivity varies

Oral(µg)
Threshold< 25 µgLight25 – 100 µgCommon100 – 250 µgStrong250 – 400 µgHeavy400+ µg

Starts in 30 – 90 minLasts 8 – 12 hoursAfter-effects 2 – 6 hours

Body and dependence

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

Tolerance

Builds
Rapid
Fully resets after
14 days
Carries over to
LSD; psilocybin; mescaline; DMT; 1P-LSD; 1cP-LSD; 1V-LSD; other 5-HT2A agonist psychedelics

Effectslikely at a common dose

Perception
Auditory enhancement; Brightness alteration; Color alteration; Color enhancement; Environmental patterning; Geometry; Holotropic state; Music enhancement; Perspective distortion; Tracers; Visual breathing; Visual drifting; Visual morphing; +24 possible, including Visual haze / noise, Spatial disorientation, Vestibular distortion
Body
Insomnia; Appetite suppression; Body high; Body scan awareness; Pupil dilation; Spontaneous body sensations; Stimulation; Wakefulness; +26 possible, including Muscle tension, Heart rate perception changes, Motor control impairment
Thinking
Immersion enhancement; Aesthetic enhancement; Cognitive flexibility; Conceptual thinking; Introspection enhancement; Multiple thought streams; Novelty enhancement; Openness enhancement; Pattern recognition enhancement; Thought acceleration; Thought connectivity; +26 possible, including Decision impairment, Suggestibility enhancement, Analysis suppression
Feeling
Euphoria; Emotional enhancement; Simultaneous emotions; +8 possible, including Emotional lability, Anxiety, Paranoia
Self
Emotional susceptibility; +13 possible, including Derealization, Depersonalization, Ego inflation
Time
Temporal disorientation; Time alteration; +3 possible
Transpersonal
none likely · 1 possible
Awareness
Personal insight; +5 possible

Who shouldn't take it

Absolute
Psychotic disorders; Pregnancy; Lithium use; MAOI use
Relative
Cardiovascular conditions; Severe anxiety disorders or psychological crisis; Iron overload conditions

Combinations61 recorded

Lethal (1)
MAOIs
Dangerous (18)
MDMA, MDA; NRIs; Buspirone; Dopamine agonists; GHB, Baclofen; GHB, GBL; Ibogaine; Ketamine, DXM, PCP; Lithium; Local anesthetics; MDMA, Amphetamines; NDRIs (Wellbutrin); Psychedelics; Salvia, Ibogaine; SNRIs; SSRIs; Stimulants; Synthetic cannabinoids
Caution (37)
See full page: psychedex.org/substances/1fe-lsd
Not graded (5)
Not listed never means safe.

Seek help immediately if

Most difficulty is psychological (intense fear, panic, confusion) and passes with calm support — the signs below mean seek emergency help:

  • Very high body temperature; hot, dry skin
  • Seizures
  • Chest pain; fast or irregular heartbeat
  • Severe muscle rigidity, tremor, or twitching (possible serotonin syndrome)
  • Cold, pale, or blue fingers/toes — severe vasoconstriction (notably NBOMe / DOx)
  • Persistent vomiting; unconsciousness; uncontrollable agitation or risk of self-harm

What to do

  1. Stay calm and reassure — remind them they took a drug and the effect will pass
  2. Move to a calm, quiet, safe space with low light; reduce noise and sensory input
  3. Keep them from harm — they may act on fear or confusion; stay with them, don't leave them alone
  4. Talk them down gently; don't grab or restrain unless they're in danger
  5. For the medical signs above (overheating, seizure, chest pain, vasoconstriction, unresponsive) call emergency services
  6. If overheating, cool the body; be ready to give rescue breaths / CPR

The experience is time-limited and usually resolves with calm reassurance in a safe setting — psychological first aid, not medication. Serious physical harm is uncommon for classic psychedelics (LSD, psilocybin) but real for some potent phenethylamines (NBOMe, DOx), where hyperthermia, seizures, and vasoconstriction warrant emergency care.

988 Suicide & Crisis LifelineFireside Project: 62-FIRESIDE

psychedex.org/substances/1fe-lsd · Version r1 · Not medical adviceValues as of
On the printout