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5-3 Psychoactive Drugs - Psychoactive drugs may cause altered states of
consciousness, modify our perceptions or change our moods. Drugs may
be legally prescribed or illegally gained and used. Illegal drug use is a
major issue across the world including among American teenagers. Drugs
may cause dependence or addiction. There are various categories of drugs
based on their effects on the body. Depressants slow down mental and
physical activity, stimulants increase CNS activity, and hallucinogens
modify a person’s perceptual experiences and produce artificial visions.
Many specific drugs within these categories may be used for medical
reasons and each has short-term effects, overdose effects, health risks, and
risk of dependence.
Uses of Psychoactive Drugs
1.
Psychoactive drugs are substances that act on the nervous system to alter states of consciousness,
modify perceptions, and change moods.
2.
Drug use for personal gratification can be dangerous because it leads to drug dependence, personal
disarray, and a predisposition to serious, sometimes fatal diseases.
3.
When a person has to take more and more of the drug to achieve the same desired effect, they have
become tolerant.
4.
Physical dependence is the physiological need for a drug. Without the drug the person exhibits
withdrawal symptoms.
Psychological dependence is a strong desire to repeat using the drug for emotional reasons.
5.
6.
For drug use to be considered an addiction there has to be a physical and/or psychological
dependence on the drug.
Psychoactive drugs cause an increase in dopamine levels in the brain’s reward system pathways,
especially in the ventral tegmental area and the nucleus accumbens.
Types of Psychoactive Drugs
7.
1.
Depressants
 Depressants slow down mental and physical activity.
a.
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Alcohol
 Alcohol acts as a depressant and slows down the brain’s activity. People may act more
free and loosen up a bit after a few drinks because the area of the brain involved in
inhibition and judgment slows down.
 Activities that involve intellectual functioning and motor skills become impaired.
 Researchers believe the frontal cortex holds a memory for the pleasure that was involved
in prior alcohol use and therefore contributes to continued drinking.
 Next to caffeine, alcohol is the most widely used drug in the United States.
 Alcoholism involves long-term, repeated, uncontrolled, compulsive, and excessive use of
alcoholic beverages that impairs the drinker’s health and social relationships.
 Fifty to sixty percent of those people that become alcoholics do so because of some
genetic disposition. This may be because the brains of people genetically predisposed to
alcoholism may be unable to produce enough dopamine, which is a neurotransmitter that
elicits pleasure.
Barbiturates
 A barbiturate is a depressant drug that decreases the activity of the central nervous
system.
 Barbiturates were originally prescribed as sleep aids.
 With increased usage they can lead to impaired memory and decision making.
Tranquilizers
 Tranquilizers are depressants that reduce anxiety and induce relaxation.
 Tranquilizers are usually prescribed to calm an anxious, nervous person.
Opiates
 Opiates consist of opium and depress the central nervous system’s activity.
 When the drugs leave the brain their synapses become understimulated.
 For many hours after taking the drug the person may feel euphoric and pain-free and have
an increased desire for food and sex.
2.
Stimulants
 Stimulants increase activity in the central nervous system.
a.
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b.
Caffeine
 Caffeine is the world’s most widely used drug.
 The term caffeinism is overindulgence in caffeine. It brings about mood changes, anxiety,
and sleep disruption. It usually occurs in people who drink five or more cups of coffee a
day.
Nicotine
 Nicotine is the main psychoactive ingredient in all forms of smoking and smokeless
tobacco.
 It is highly addictive. It stimulates the brain’s rewards centers by raising dopamine levels.
 Behavioral effects include improved attention and alertness, reduced anger and anxiety,
and pain relief.
c.
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 Amphetamines are also known as “uppers” and people use them to boost energy, stay
awake, or lose weight. They are often prescribed as diet pills.
 They increase the release of dopamine, which enhances the user’s activity level and
causes pleasurable effects.
 Crystal meth is probably the most insidious illicit drug. It causes a strong euphoric
feeling, especially the first time it is taken.
Cocaine
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Amphetamines
 Cocaine comes from the coca plant. It is either snorted or injected in the form of crystals
or powder.
 It enters the bloodstream quickly, producing a rush of euphoric feelings that lasts for
about 15-30 minutes.
 Crack is a potent form of cocaine. It is believed to be one of the most addictive
substances known, even more so than heroine, barbiturates, and alcohol.
MDMA (Ecstasy)
 MDMA has both stimulant and hallucinogenic properties.
 Street names are Ecstasy, X, XTC, hug, beans, and love drug.
 It has adverse effects on memory and cognitive processing.
3.
Hallucinogens
 Hallucinogens modify a person’s perceptual experiences and produce visual images that
are not real.
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Marijuana
 Marijuana comes from the dried leaves and flowers of the hemp plant.
 The active ingredient in marijuana is THC, which does not affect a specific
neurotransmitter. However, it does disrupt the membranes of neurons and affects the
functioning of many neurotransmitters and hormones.
 The physical effects include an increase in pulse rate and blood pressure, reddening of the
eyes, coughing, and dryness of the mouth.
 Psychological effects include a mixture of excitatory, depressive, and mildly
hallucinatory characteristics that make it difficult to classify the drug.
 It can impair attention and memory. When used in large amounts, it can alter sperm count
and change hormonal cycles.
LSD
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 When using LSD, objects can appear to change their shape and glow. Colors become like
a kaleidoscope and amazing images unfold. Time seems to slow down.
 LSD’s effects on the body include dizziness, nausea, and tremors.
 It acts primarily on the neurotransmitter serotonin, but it can also affect dopamine.