Question

What are the three categories of psychoactive substances?

This question is for a narcotics class

Answer 1

Psychoactive drugs - chemical substances that alter perceptions and moods

Substance abuse disorder - a disorder characterized by continued substance craving and use despite significant life disruption and/or physical risk.

The three categories - depressants, stimulants, and hallucinogens - are important.

Depressants and their effects

Drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions.

a) Alcohol - Alcohol is a central nervous system (CNS) depressant; meaning it slows neural activity in the brain and spinal cord. GABA, an inhibitory neurotransmitter, and glutamate, an excitatory neurotransmitter, both interact with alcohol to produce the effects we associate with drinking. When alcohol enters the body, it acts as an agonist with inhibitory GABA receptors making them inhibitorier. MRI scans show brain shrinkage (enlarged ventricles) in women with alcohol use disorder (left) compared with women in a control group (right). Slowed neural processing cause’s reactions to slow, speech to slur, and skilled performance to deteriorate. Alcohol can disrupt memory formation, and heavy drinking can also have long-term effects on the brain and cognition. Alcohol suppresses REM sleep, which is needed for memory consolidation.

b) Barbiturates - drugs that depress central nervous system activity, reducing anxiety but impairing memory and judgment. Barbiturates such as Nembutal, Seconal and Amytal are sometimes prescribed to induce sleep or reduce anxiety. In larger doses, they can impair memory and judgment. If combined with alcohol, the total depressive effect on body functions can be lethal.

c) Opiates - Opium and its derivatives, such as morphine and heroin; depress neural activity, temporarily lessening pain and anxiety. As blissful pleasure replaces pain and anxiety, the user’s pupils constrict, breathing slows, and the person becomes lethargic. Those who become addicted to this short-term pleasure may pay a long-term price: a gnawing craving for another fix, a need for progressively larger doses (as tolerance develops), and the extreme discomfort of withdrawal. When repeatedly flooded with an artificial opiate, the brain eventually stops producing endorphins, its own opiates. If the artificial opiate is then withdrawn, the brain will lack the normal level of these painkilling neurotransmitters. In recent years, more and more people have been unable or unwilling to tolerate this state and have paid an ultimate price - death by overdose.

Stimulants and their effects

Drugs (such as caffeine, nicotine, and the more powerful cocaine, amphetamines, methamphetamine, and Ecstasy) that excite neural activity and speed up body functions. People use stimulants to feel alert, lose weight, or boost mood or athletic performance.

a) Nicotine - a stimulating and highly addictive psychoactive drug found in tobacco. Tobacco products include cigarettes, cigars, chewing tobacco, pipe tobacco, snuff, and e-cigarettes (vaping). Virtually nobody starts smoking past the vulnerable teen years. Eager to hook customers whose addiction will give them business for years to come, cigarette companies target teens. Nicotine reaches the brain within 7 seconds, twice as fast as intravenous heroin. Within minutes, the amount in the blood soars.

b) Cocaine - a powerful and addictive stimulant derived from the coca plant; produces temporarily increased alertness and euphoria Cocaine is snorted, injected, or smoked. It enters the bloodstream quickly, producing a rush of euphoria that depletes the brain’s supply of the neurotransmitters dopamine, serotonin, and norepinephrine.

c) Methamphetamine - a powerfully addictive drug that stimulates the central nervous system, with accelerated body functions and associated energy and mood changes; over time, appears to reduce baseline dopamine levels. “Meth’s” aftereffects may include irritability, insomnia, hypertension, seizures, social isolation, depression, and occasional violent outbursts.

d) Ecstasy - a synthetic stimulant and mild hallucinogen produces euphoria and social intimacy, but with short-term health risks and longer-term harm to serotonin producing neurons and to mood and cognition. As an amphetamine derivative, Ecstasy (MDMA) triggers dopamine release, but its major effect is releasing stored serotonin and blocking its reuptake, thus prolonging serotonin’s feel-good flood. Ecstasy’s dehydrating effect, can lead to severe overheating, increased blood pressure, and death.

Hallucinogens and their effects

Psychedelic (“mind-manifesting”) drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input.

a) LSD - a powerful hallucinogenic drug; also known as acid (lysergic acid diethylamide). The emotions of an LSD (or acid) trip vary from euphoria to detachment to panic. Users’ mood and expectations (their “high hopes”) influence the emotional experience, but the perceptual distortions and hallucinations have some commonalities.

b) Marijuana (cannabis) and THC - Marijuana (cannabis) is usually classified as a mild hallucinogen because it amplifies sensitivity to colors, sounds, tastes, and smells. But like alcohol, marijuana also relaxes, disinhibits, and may produce a euphoric high. Marijuana leaves and flowers contain THC (delta-9- tetrahydrocannabinol), the psychoactive ingredient. Whether smoked or eaten THC produces a mix of effects.