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Common Abused Drugs and their Effects

Psychoactive Drugs


Psychoactive drugs are substances that change the way people feel, think, or behave. This includes plants that are used as drugs as well as drugs that are synthesized from chemicals.


Some psychoactive drugs have legitimate uses in the proper dose. The pioneer of pharmacology, Paracelsus[i], wrote, “Dose alone determines whether or not something is a poison.” The excessive doses used for recreational purposes can be very harmful physically as well as psychologically. For some synthetic drugs, there are no medicinal uses and no safe doses. Psychoactive drugs are addictive, and their abuse is potentially destructive to oneself and others.


-Major Categories




Stimulants include cocaine and amphetamines, as well as milder stimulants such as tobacco and coffee. People can become highly dependent on stimulants. Among the potential effects are increased alertness of mind and body, increased pulse rate and blood pressure, euphoria, insomnia, loss of appetite, and an illusion of well-being. When people have become accustomed to stimulants and can no longer obtain them, they can experience depression, disorientation, apathy, and long periods of sleep.




This category includes narcotics such as opium and heroin, tranquilizers such as barbiturates, sedatives such as alcohol, and anesthetics found in many inhalants. Narcotics relieve pain and produce euphoria, drowsiness, and constricted pupils; depressants slow down physical and mental functions. People can become very dependent on depressants; overdoses of heroin can cause coma and death. When people have become accustomed to depressants and can no longer obtain them, they can experience loss of appetite, nausea, chills, cramps, tremors, anxiety, insomnia, delirium, and panic.




Psychedelics include cannabis, hallucinogens such as mescaline (from peyote), and synthetic compounds such as LSD and PCP. Potential effects include distorted perceptions, altered thinking and emotions, hallucinations, poor motor coordination, and relaxed inhibitions. These substances may not be highly addictive, but users risk losing touch with reality.


-Commonly Abused Drugs




Cocaine is produced from coca plants grown in South America. Cocaine produces sensations of great energy and the illusion of well-being. It is extremely addictive, causing erratic behavior and strained relationships, leading to a progressive decay of a person's social life. Even a single use of cocaine can cause death. Crack, a purified form of cocaine causing paranoia and violence, has become a serious problem because it is rather inexpensive and easy to obtain.




These are often called “speed,” amphetamines speed up the heartbeat, breathing, blood pressure, and body temperature. They give the user a sense of power and alertness, but this can be accompanied by sleeplessness, irritation, dizziness, blurred vision, anxiety, and panic attacks. Amphetamines are less addictive than cocaine, but large doses can cause death by stroke or heart failure.




Heroin blocks pain and provides pleasure by imitating the body's natural pain-killing chemicals called endorphins. It is highly addictive, causing severe physical and psychological dependence. Heroin can give a sense of well-being, but this can be accompanied by vomiting, sleepiness, loss of balance, loss of concentration, and loss of appetite. Injecting heroin creates a powerful high, but users often share needles without sterilizing them, risking the spread of HIV. Large doses can lower the blood pressure and heart rate, bringing coma and death.


Marijuana (cannabis)


Marijuana, produced from the cannabis plant, induces pleasant sensations and sometimes mild hallucinations. However, repeated use of the drug impairs learning and memory and leads to sluggishness and low motivation. Sophisticated breeding techniques have made cannabis three to seven times more potent than before. It is often laced with other drugs such as heroin, PCP, or cocaine.




LSD (lysergic acid diethylamide) is a powerful psychedelic drug, causing hallucinations. The user experiences a “trip” to a world that may be full of delights or full of terrors. Users may experience suspicion, confusion, anxiety, panic, and loss of control. Delayed effects, or flashbacks, can occur even a long time after people stop using the drug.




PCP (phencyclidine) affects perception, memory, concentration, and judgment in unpredictable ways. Users often have delusions of extraordinary abilities and think they can do anything. PCP sometimes unleashes violent behavior, with users flying into a rage and killing people. It can also cause temporary madness; some PCP users have jumped from buildings thinking they could fly.




Inhalants are chemicals found in ordinary household products, such as glue, nail polish, and aerosol sprays. They are not drugs and can be easily purchased and used by young adolescents and their perceived risk is low[ii] which explains the increase of young people abusing them. When inhaled, these vapors cause brief numbness and a feeling of being high. They can cause drowsiness, headaches, nausea, fainting, fast heartbeat, and disorientation. Prolonged use can cause brain, lung, kidney, and liver damage, and even death.


Designer drugs


Drugs are defined in terms of their basic chemical formulas. To bypass legal restrictions, underground chemists modify the molecular structure of psychoactive drugs to produce similar compounds, known as designer drugs. These can be much stronger than the drugs they imitate.

One such drug, ecstasy, has become popular at teen clubs. Like amphetamines, ecstasy speeds up the nervous system by increasing physical and emotional energy levels. Users may feel happy, warm, loving, and more energetic; however, ecstasy can overheat the body and cause dehydration. Prolonged use can lead to brain or liver damage.


Another designer drug is rhypnol (known as “roofie”). A tasteless, colorless sleeping agent, it can be slipped into a drink without the victims' knowledge, causing them to pass out. Young women have reported waking up after a party in unfamiliar surroundings with unfamiliar people. Such circumstances can lead to robbery and rape.


The Institute for Social Research reported their 2014 findings of the growing trend of ecstasy use at even younger ages. “The erosion in perceived risk and disapproval -- which was sharpest among 8th graders -- left these groups more vulnerable to a possible rebound in use; some rebound appears to have occurred over the past decade.”[iii]


Anabolic steroids


Anabolic steroids are closely related to the male sex hormone, testosterone. Taken in combination with muscle building exercises and diet, steroids may contribute to an increase in body weight and muscular strength. Athletes sometimes use steroids hoping to enhance their performance, and young people may use steroids hoping to speed up their physical development. However, there are more than 70 harmful side effects to steroid use, including damage to the liver, heart, and reproductive organs. Psychological effects may include sudden aggressive behavior and depression.


-Gateway Drugs: Alcohol and Tobacco


It seems that using one psychoactive drug opens the way to using more. Alcohol and tobacco predispose people to try harder drugs such as cocaine and heroin. Young people are more likely to try hard drugs if they have tasted the intoxication of alcohol or marijuana and inhaled the smoke of cigarettes. Alcohol and tobacco, along with marijuana, are called “gateway drugs.”


Tobacco contains nicotine, which is a highly addictive drug. Smoking cigarettes is not a casual habit, but is driven by addiction to nicotine. As the body becomes habituated, smokers may need to smoke 40 or 50 cigarettes a day to receive the same feeling. Tobacco is the leading preventable cause of premature death in the United States, where an estimated 480,000 people die every year of from 21 diseases (12 types of cancer, 6 categories of cardiovascular disease, diabetes, chronic obstructive pulmonary disease, and pneumonia) brought on by tobacco use.[iv]  The US Department of Health and Human Services reports:


Tobacco use is a global epidemic among young people. As with adults, it poses a serious health threat to youth and young adults in the United States and has significant implications for this nation’s public and economic health in the future (Perry et al. 1994; Kessler 1995). The impact of cigarette smoking and other tobacco use on chronic disease, which accounts for 75% of American spending on health care (Anderson 2010), is well-documented and undeniable. Although progress has been made since the first Surgeon General’s report on smoking and health in 1964 (U.S. Department of Health, Education, and Welfare [USDHEW] 1964), nearly one in four high school seniors is a current smoker. Most young smokers become adult smokers.[v]


Tobacco companies have aggressively promoted smoking in the developing nations. The World Health Organization estimates that currently tobacco use:


[It] kills nearly 6 million people and causes hundreds of billions of dollars of economic damage worldwide each year… If current trends continue, by 2030 tobacco will kill more than 8 million people worldwide each year, with 80% of these premature deaths among people living in low- and middle-income countries. Over the course of the 21st century, tobacco use could kill a billion people or more unless urgent action is taken[vi]


Alcohol is humanity's oldest intoxicant, used since ancient times. The pleasure of alcohol comes from its chemical effect on the brain as a depressant, thereby reducing anxiety, helping people forget their worries, and lowering their inhibitions. Alcohol abuse impairs judgment and coordination, a serious problem when people are driving a car or operating machinery. Children born to alcoholic mothers may suffer physical and mental impairment. Long-term alcohol abuse causes liver damage.


Due to the lessening of inhibitions against immoral behavior, alcohol use among college students in America has become a significant public health hazard that affects the intellectual and social lives of students on campuses across the country. The National Institute of Alcohol Abuse and Alcoholism[vii] reported how many United States college students between the ages of 18 and 24 suffer the following consequences:


  • Death: 1,825 die each year from alcohol-related unintentional injuries.

  • Assault: More than 690,000 are assaulted by another student who has been drinking.

  • Sexual Abuse: More than 97,000 are victims of alcohol-related sexual assault or date rape.

  • Unsafe Sex: An estimated 400,000 have unprotected sex. 100,000 report having been too intoxicated to know if they consented to having sex.

  • Injury: 599,000 receive unintentional injuries while under the influence of alcohol.

  • Academic Problems: About 25 percent of college students report academic consequences of their drinking including missing class, falling behind, doing poorly on exams or papers, and receiving lower grades overall.

  • Health Problems/Suicide Attempts: More than 150,000 students develop an alcohol-related health problem and between 1.2 and 1.5 percent of students indicate that they tried to commit suicide within the past year due to drinking or drug use.


Unfortunately, the prevalence of alcohol abuse among middle and high school youth is high:

“In 2013 one eighth of all 8th graders (12%), one third of 10th graders (34%), and about a half of all 12th graders (52%) said they had been drunk at least once in their lifetime.”[viii]


Although many people can control their alcohol consumption, a certain percentage of the population is genetically susceptible to alcoholism. Sometimes called legal drugs because they are sold publicly, cigarettes and alcohol have psychoactive properties and can create addiction. Because of their widespread use, they are responsible for more health problems than all other drugs combined.


The probability that a 12- to 17-year-old smoker will one day use cocaine is 19 times greater than a non-smoker. A teenage drinker is 50 times more likely to one day use cocaine than someone who does not drink. A teenager who smokes marijuana is 85 times more likely to use cocaine than one who never smokes marijuana.[ix] Conversely, if people have never used alcohol, marijuana, or tobacco before the age of 21, it is very unlikely that they will ever use harder drugs.


Teen users are at significantly higher risk of developing an addictive disorder compared to adults, and the earlier they began using, the higher their risk. Nine out of 10 people who meet the clinical criteria for substance use disorders involving nicotine, alcohol, or other drugs began smoking, drinking, or using other drugs before they turned 18. People who begin using any addictive substance before age 15 are six and a half times as likely to develop a substance use disorder as those who delay use until age 21 or older (28.1 percent vs. 4.3 percent).[x]




[i] Theophrastus Bombastus von Hohenheim, called Paracelsus (1493-1 541 ), was a Swiss alchemist and medical doctor. He pioneered the modern science of pharmacology.


[ii] Johnston, L. D., O’Malley, P. M., Miech, R. A., Bachman, J. G., & Schulenberg, J. E., Monitoring the Future national survey results on drug use: 1975-2014: Overview, key findings on adolescent drug use. Ann Arbor: Institute for Social Research, The University of Michigan. 2015, p.16.


[iii] Ibid., p.36.


[iv] Brian D. Carter, M.P.H., Christian C. Abnet, Ph.D., et al., “Smoking and Mortality — Beyond Established Causes,” New England Journal of Medicine, Feb 12, 2015;372:631-40. DOI: 10.1056/NEJMsa1407211.


[v] US Department of Health and Human Services. “Preventing Tobacco Use Among Youth and Young Adults: A Report of the Surgeon General.” Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2012, p. 3.


[vi] “WHO Report on the Global Tobacco Epidemic, 2011: Warning About the Dangers of Tobacco,” World Health Organization, Geneva, Switzerland, 2011, p. 8.


[vii] “College Drinking Fact Sheet.” College Drinking. National Institute of Alcohol Abuse and Alcoholism, July 2013.


[viii] Johnston, L. D., O’Malley, P. M., Bachman, J. G., Schulenberg, J. E. & Miech, R. A., Monitoring the Future national survey results on drug use, 1975–2013: Volume I, Secondary school students. Ann Arbor: Institute for Social Research, The University of Michigan, 2014, pp. 90-91.


[ix] “Marijuana and Youth, The Fact Is ... ,”Join Together, 1996.


[x] “Adolescent Substance Abuse: America's #1 Public Health Problem,” National Center on Addiction and Substance Abuse at Columbia University, June 2011, p. 2.

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