Psychoactive

A psychoactive drug or psychotropic substance is a chemical that alters brain function, resulting in temporary changes in perception, mood, consciousness, or behaviour. Such drugs are often used for recreational and spiritual purposes, as well as in medicine, especially for treating neurological and psychological illnesses.

Psychoactive drug chart

Legend

• Blue: Stimulants generally increase in potency to the upper left
• Red: Depressants generally increase in potency to the lower right
• Green: "Hallucinogens" are psychedelic to the left, dissociative to the right, and generally less predictable down and to the right
• White: Cannabis, though considered psychedelic at high doses, stands on its own

Other psychoactive drugs

• Aphrodisiacs
  • PT-141

• In a broader sense also:
  • Antiemetics
  • Analgesics
  • Antiepileptics

Ways Psychoactive Drugs Affect The Brain

There are many ways in which psychoactive drugs can affect the brain. While some drugs affect neurons presynaptically, others act postsynaptically and some drugs don't even attack the synapse, working on neural axons instead. Here is a general breakdown of the ways psychoactive drugs can work.

1. Prevent The Action Potential From Starting
   • Lidocaine, TTX (they bind to voltage-gated sodium channels, so no action potential begins even when a generator potential passes threshold)
2. Neurotransmitter Synthesis
   • Increase - L-Dopa, tryptophan, choline (precursors)
   • Decrease - PCPA (inhibits synthesis of 5HT)
   • Causes increased sensitivity to the five senses, due to an increasing number of signals being sent to the brain.
3. Neurotransmitter Packaging
   • Increase - MAO Inhibitors
   • Decreasing - Resperine (pokes holes in the synaptic vesicles of catecholamines)
4. Neurotransmitter Release
   • Increase - Black Widow Spider (Ach)
   • Decrease - Botulinum Toxin (Ach), Tetanus (GABA)
5. Agonists - Mimic the original NTs and activate the receptors
   • Muscuraine, Nicotine (Ach)
   • AMDA, NMDA (Glu)
   • Alcohol, Benzodiazepines (GABA)
6. Antagonists - Bind to the receptor sites and block activation
   • Atropine, Curare (Ach)
   • PCP (Glu)
7. Prevent Ach Breakdown -
   • Insecticides, Nerve Gas
8. Prevent Reuptake
   • Cocaine (DA), Amphetamines (E)
   • Tricyclics, SSRIs

- based on information taught in NSC 201, Vanderbilt University

Related articles

• Drug
• Stimulant
• Depressant
• Psychedelics, Dissociatives and Deliriants

External links

• Erowid
• Spirit Plants
• Drug Wise Newsletter: A Newsletter on Psychotropic Drugs