LSD Facts
Psychedelic;
Description
LSD (lysergic acid diethylamide) — acid, tabs, blotter, Lucy — is a semi-synthetic psychedelic of the lysergamide class. It activates serotonin receptors in the brain, disrupting the brain's normal filtering of sensory and cognitive input.[1]
Subjective effects include geometric visual patterns, intensified colors, time alteration, accelerated thought, and ego dissolution — the sense that the self's boundaries have dissolved. The experience is slow-building and all-encompassing, with a stimulating, electric quality that distinguishes it from psilocybin mushrooms.[2]
LSD produces no physical dependence and has no confirmed lethal dose in humans.[3] The primary risks are psychological — high doses can produce panic, paranoid thinking, and dangerous behavior, and combining LSD with lithium causes seizures in roughly half of documented cases.
Dose and durationby route · individual sensitivity varies
Starts in 20 – 45 minLasts 7 – 12 hoursAfter-effects 6 – 48 hours
Body and dependence
- Acute toxicity
- Negligible
- Chronic toxicity
- Low
- Physical dependence
- None
- Psychological dependence
- Negligible
- Withdrawal
- None recorded
- Compulsive redosing
- Negligible
Tolerance
- Builds
- Rapid
- Fully resets after
- 14 days
- Carries over to
- psilocybin;
mescaline; DMT; psilocin; 2C-B; 2C-E; 2C-I
Effectslikely at a common dose
- Perception
- Auditory enhancement;
Geometry; Visual drifting; Visual breathing; Visual morphing; Color enhancement; Music enhancement; Tracers; +24 possible, including Visual haze / noise, Spatial disorientation, Vestibular distortion - Body
- Wakefulness;
Insomnia; Stimulation; Pupil dilation; Body high; Body scan awareness; +20 possible, including Temperature dysregulation, Heart rate perception changes, Muscle tension - Thinking
- Thought connectivity;
Conceptual thinking; Novelty enhancement; Aesthetic enhancement; Pattern recognition enhancement; Thought acceleration; +26 possible, including Language suppression, Confusion, Decision impairment - Feeling
- Emotional enhancement;
Euphoria; +5 possible, including Emotional lability - Self
- none likely · 7 possible, including Communication suppression
- Time
- Time alteration;
+2 possible, including Temporal disorientation - Awareness
- none likely · 8 possible
Who shouldn't take it
Combinations61 recorded
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
- Stay calm and reassure — remind them they took a drug and the effect will pass
- Move to a calm, quiet, safe space with low light; reduce noise and sensory input
- Keep them from harm — they may act on fear or confusion; stay with them, don't leave them alone
- Talk them down gently; don't grab or restrain unless they're in danger
- For the medical signs above (overheating, seizure, chest pain, vasoconstriction, unresponsive) call emergency services
- 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
References
- [1]^Holze F, Vizeli P, Müller F, Ley L, Duerig R, Varghese N, Zizzari P, Liechti ME (2021) Acute dose-dependent effects of lysergic acid diethylamide in a double-blind placebo-controlled study in healthy subjects — Neuropsychopharmacology doi:10.1038/s41386-020-00883-6
- [2]^Ley L, Holze F, Arikci D, Becker AM, Straumann I, Klaiber A, Coviello F, Dierbach S, Thomann J, Duthaler U, Luethi D, Varghese N, Eckert A, Liechti ME (2023) Comparative acute effects of mescaline, lysergic acid diethylamide, and psilocybin in a randomized, double-blind, placebo-controlled cross-over study in healthy participants — Neuropsychopharmacology doi:10.1038/s41386-023-01607-2
- [3]