Comprehensive Guide to Psychoactive Drugs: Names, Routes, and Effects on Brain and Behavior

Psychopharmacology

Study of the ways drugs affect the nervous system and behavior

Chemical name

Describes a drug's complex molecular structure

Generic name

Name of the drug's active ingredient; often a shortened, simpler version of the chemical name

Brand name

Unique trademarked name given by the manufacturer

Blood Plasma

The liquid component of your blood; contributes to 55% of your blood's total volume

Absorption Rate

The time to reach maximum plasma concentration

Blood-Brain Barrier (BBB)

Endothelial cell walls in capillaries in the brain fit together tightly, forming 'tight' junctions

Astrocytes

Supportive cells in the brain that help maintain the blood-brain barrier

BBB-Free Brain Sites

Specialized brain regions where the BBB is weak or absent

Circumventricular Organ (CVO)

Specialized brain regions where the BBB is weak or absent, allowing communication with the blood

Metabolism

The process by which the body breaks down drugs into more water-soluble compounds for easier excretion

Cytochrome p450 enzyme family

Involved in the metabolism of drugs in the liver

Excretion

The process of eliminating metabolized drugs through urine, feces, sweat, breast milk, and exhaled air

Neurotransmission

The process by which neurotransmitters are released, activate receptors, and are removed from the synapse

Agonist

A substance that binds to a receptor and activates it, producing a biological response similar to the natural neurotransmitter

Antagonist

A substance that binds to a receptor but does not activate it, blocking or reducing the effect of the natural neurotransmitter

Competitive binding

Occurs at the neurotransmitter binding site where the drug competes with the neurotransmitter to bind to the receptor

Non-competitive binding

Occurs at an alternate binding site on the same receptor

Direct agonist

A type of competitive binding that directly activates the receptor

Direct antagonist

A type of competitive binding that directly blocks receptor activation

Indirect agonist

A type of non-competitive binding that enhances receptor activation

Indirect antagonist

A type of non-competitive binding that weakens receptor activation

Psychoactive drug

A chemical substance that changes the function of the nervous system and results in alterations of perception, mood, cognition, and behavior

Group 1

Antianxiety Agents and Sedative Hypnotics

Group 2

Antipsychotic Agents

Group 3

Antidepressants

Group 4

Opioid Analgesics

Group 5

Psychotropics

Behavioral Stimulants

A category of psychotropic drugs that enhance behavior.

Psychedelic and Hallucinogen Stimulants

Substances that alter perception and cognition.

General Stimulants

Drugs that increase alertness and energy.

Barbiturates

Indirect agonist of GABA-A receptors with sedative-hypnotic properties.

Benzodiazepines

Indirect agonist of GABA-A receptors with anti-anxiety properties.

Ketamine

Used medically for induction and maintenance of anesthesia or pain management.

Xylazine

Nn-opiod sedative or tranq used for sedation, anesthesia, muscle relaxation, and analgesia in animals.

Antipsychotic Agents

Type of psychoactive drugs to treat psychosis.

Psychosis

A mental state characterized by a loss of contact with reality.

First-Generation Antipsychotics

Mainly D2 receptor antagonists that also block noradrenergic, cholinergic, and histamine receptors.

Second-Generation Antipsychotics

D2 and 5-HT2 receptor antagonists that increase selectivity, enhancing effect and lowering side effects.

Antidepressants

A class of drugs used to treat depression and related mood disorders.

Major Depressive Disorder (MDD)

Characterized by prolonged feelings of worthlessness and guilt, general slowing of behavior, and frequent thoughts of suicide.

Tricyclic Antidepressants (TCAs)

Inhibit the reuptake of serotonin and norepinephrine.

Monoamine Oxidase Inhibitors (MAOIs)

Block the monoamine oxidase enzyme responsible for the degradation of serotonin, dopamine, and norepinephrine.

Selective Serotonin Reuptake Inhibitors (SSRIs)

Increase the amount of 5-HT in the brain by inhibiting serotonin uptake.

Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs)

Increase the amount of 5-HT and norepinephrine by blocking the reuptake system.

Therapeutic lag

The 2-3 weeks period indicating that simply elevating serotonin levels alone will not treat depression.