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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. 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. 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. 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 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. a. 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 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.