Psychedelic Drugs: Classification and Effects

Psychedelic Drugs: Classification and Effects

• Anticholinergic:
  • Scopolamine (mAch antagonist): Low doses cause sedation, mild euphoria, and amnesia; high doses cause euphoria, hallucinations, and excitement. Peripheral effects include tachycardia, increased body temperature, and dry mouth. Used in twilight anesthesia.

Serotonergic Psychedelics

• LSD (Lysergic Acid Diethylamide):

  • Chemically similar to serotonin.
  • Developed in the 1930s to explore therapeutic possibilities (vasoconstriction) and, later, as a model of psychosis.
  • Binds to 5-HT2A receptors in the brain (prefrontal and cingulate cortex). Causes perceptual distortions (visual, auditory, space/time).
  • Synthesized in 1938.
  • Used in psychotherapy and by military in the 1950s-1970s.
  • Illegal (felony-level possession) since 1968.

• Ololiuqui:

  • Seeds of morning glory.
  • Psychedelic compound: lysergic acid amide (not the same as LSD).

• Bufotenine:

  • Alternative metabolite of serotonin.
  • Found in people with psychiatric disorders (?).
  • Found in the skin of toads of the genus Bufo.

• Psilocybin/Psilocin:

  • Found in "shrooms" (mushrooms).
  • Renewed interest in their use as adjunctive treatment for depression, PTSD, addiction, and end-of-life anxiety.

Catecholamine-like Psychedelics

• Mescaline:

  • Chemically similar to norepinephrine and dopamine.
  • Methoxy groups confer psychedelic properties by acting as agonists at the 5-HT2A receptor.
  • Causes anxiety, visual distortions, and tremors.

• Synthetic Methoxylated Amphetamine Derivatives (DOM, MDA, DMA, MDE, TMA, AMT, MDMA):

  • Increase the release of or inhibit the reuptake of monoamines and acetylcholine.
  • MDMA (Ecstasy):

• Developed in 1914 for appetite suppression.

• Tested by US military as a "brainwashing" drug in the 1950s.

• Interest in its use as psychological treatment in the 1970s.

• Popular among college students since the 1980s.

• Effects include empathy, insight, enhanced communication, and transcendent religious experiences.

• Potential for sympathomimetic effects (like anxiety), malignant hyperthermia, and neurotoxicity.

Antiglutamatergic Psychedelics

• Phencyclidine (PCP) and Ketamine:
  • NMDA receptor antagonists.
  • Can cause confusion, altered perception, stupor, and coma.
  • Originally developed as safer anesthetic and analgesic agents.

Kappa Opioid Agonist

• Salvinorin A:
  • Causes hallucinations and dysphoria.