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LSA Facts

Psychedelic; Lysergamide; Serotonin 2A receptor agonist

Description

LSA (lysergic acid amide) — also known as ergine — is a naturally-occurring psychedelic of the lysergamide class. It activates serotonin receptors in the brain, producing perceptual shifts with an unusually strong sedative component compared to other classical psychedelics.[1]

Subjective effects include euphoria, visual hallucinations, dreamlike sedation, time alteration, introspective thought, and muscle weakness.[2] The experience is heavier and more inward-turning than LSD — a weighted, dreamlike state with less visual elaboration.[1]

LSA does not produce physical dependence, and no lethal dose has been established.[2] The primary physical danger is vasoconstriction — it caused one documented brain pressure crisis with seizures,[3] compounded by seed alkaloid content that varies up to 8.6-fold between products.[4]

Dose and durationby route · individual sensitivity varies

Oral(mg)
Threshold< 0.5 mgLight0.5 – 1.5 mgCommon1.5 – 4 mgStrong4 – 8 mgHeavy8+ mg

Starts in 30 – 120 minLasts 4 – 10 hoursAfter-effects 6 – 24 hours

Body and dependence

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

Tolerance

Builds
Rapid
Fully resets after
7 days
Carries over to
LSD; psilocybin; mescaline; DMT; DOI

Effectslikely at a common dose

Perception
Sleep-transition hallucinations; +32 possible, including Spatial disorientation, Vestibular distortion, Visual haze / noise
Body
Sedation; Nausea; Pupil dilation; Vasoconstriction; Bodily heaviness; +28 possible, including Muscle tension, Motor control impairment, Dizziness
Thinking
none likely · 32 possible, including Thought loops, Cognitive impairment, Language suppression
Feeling
none likely · 8 possible, including Anxiety, Emotional lability, Paranoia
Self
none likely · 7 possible, including Depersonalization, Derealization, Social disconnection
Time
none likely · 4 possible, including Temporal disorientation
Transpersonal
none likely · 1 possible
Awareness
none likely · 4 possible

Who shouldn't take it

Absolute
Pregnancy
Relative
Hypertension; Cardiovascular disease; Cerebrovascular disease; Epilepsy; Psychotic disorders; Bipolar disorder; Concurrent serotonergic medication

Combinations61 recorded

Lethal (1)
MAOIs
Dangerous (17)
Dopamine agonists; Lithium; MDMA, MDA; NRIs; GHB, Baclofen; GHB, GBL; Ibogaine; Ketamine, DXM, PCP; Local anesthetics; MDMA, Amphetamines; NDRIs (Wellbutrin); Psychedelics; Salvia, Ibogaine; SNRIs; SSRIs; Stimulants; Synthetic cannabinoids
Caution (38)
See full page: psychedex.org/substances/lsa
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

Version r1 · Not medical advice

References

  1. [1]
    ^abCastro P, Maia J (2024) Investigating LSA - a 'legal high' analogue to LSD, frequently used in the digital realm with relatively unknown effects — European Psychiatry doi:10.1192/j.eurpsy.2024.1150
  2. [2]
    ^abCastro PSCC, Leopoldo K, Pedro MOP, Takitane J, Bombana HS, Negrao AB, Scholz JR, Castaldelli-Maia JM (2025) Lysergic Acid Amide (LSA), an LSD Analog: Systematic Review of Pharmacological Effects, Adverse Outcomes, and Therapeutic Potentials — Pharmacy (Basel, Switzerland) doi:10.3390/pharmacy13040098
  3. [3]
    ^Legriel S, Bruneel F, Spreux-Varoquaux O, Birenbaum A, Chadenat ML, Mignon F, Abbosh N, Henry-Lagarrigue M, Revault D'Allonnes L, Guezennec P, Troche G, Bedos JP (2008) Lysergic Acid Amide-Induced Posterior Reversible Encephalopathy Syndrome with Status Epilepticus — Neurocritical Care doi:10.1007/s12028-008-9096-5
  4. [4]
    ^Paulke A, Kremer C, Wunder C, Wurglics M, Schubert-Zsilavecz M, Toennes SW (2014) Identification of legal highs — ergot alkaloid patterns in two Argyreia nervosa products — Forensic Science International doi:10.1016/j.forsciint.2014.06.025
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