Drug abuse and dependence
Drug abuse and dependence (Forensic Science)
Drugs are psychoactive substances that affect moods and behaviors by altering brain chemistry and function. Drugs of abuse include medically prescribed (barbiturates and pain relievers), legal (cigarettes and nicotine), and illegal (marijuana and heroin) substances. Some drugs, such as alcohol, have been used since ancient times, whereas others, such as methamphetamine and so-called designer drugs, are relatively new. People consume drugs to feel good (some drugs result in feelings of euphoria, confidence, and relaxation), to keep from feeling bad (some drugs combat feelings of anxiety, depression, and hopelessness), to accelerate performance (some drugs heighten alertness and enhance physical strength and prowess in athletic competition), and to experience altered sensory perceptions (some drugs cause users to see or hear unusual or unreal phenomena).
Drugs of abuse can be placed into five major classes according to their effects. The first class consists of stimulants, which increase alertness and decrease fatigue. Examples of stimulant drugs are amphetamines, Benzedrine, caffeine, Dexedrine, ephedrine, and nicotine. The second class consists of depressants, which reduce tension, alleviate nervousness, and induce sedation. Examples of sedative drugs are barbiturates (such as Nembutal, Seconal, Tunial, and Veronal), Valium, and Xanax. The third class consists of hallucinogens, which change sensory perceptions. Examples of hallucinogens are...
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The Addictive Process (Forensic Science)
Drug use can escalate to abuse or dependence problems, which are also called substance-use disorders. The progression to uncontrolled use depends on several risk factors. For example, biological factors play a role in addiction—that is, genetics can predispose an individual to addictive behavior. Such a predisposition is shared among close biological relatives. Scientists estimate that genes account for nearly half of a person’s vulnerability to a substance-use disorder.
Age of first use and psychiatric history are also important elements in risk for problems with drug use. Younger users are more likely to become addicted because developing adolescent brains are more susceptible to drugs’ ability to change brain chemistry and function. Persons with mental illness are also more likely to abuse or become dependent on drugs. In addition, exposure to parents’ or peers’ use of drugs can increase the risk of addiction. The mode of drug ingestion can also increase the potential for drug abuse and dependence. A drug that is inhaled or injected intravenously is more addictive than a drug that is ingested orally. The former reaches the brain faster and produces more intense highs and lows. Drug-seeking behavior intensifies in response to the cycle of peaks and valleys that the user experiences.
Psychoactive drugs are thought to become addictive through their activation of the brain’s mesocorticolimbic dopamine...
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Substance-Use Disorders (Forensic Science)
Substance-abuse and -dependence disorders are diagnosed according to the criteria specified in the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders. A substance-abuse disorder is diagnosed when drug use in the past twelve months leads to significant distress and impairment in functioning and meets at least one of the following diagnostic criteria: failure to fulfill obligations at work, school, or home; recurring use of substances in dangerous situations (such as driving while intoxicated); recurring substance-use-related criminal justice involvement; and continued substance use that leads to interpersonal conflicts.
A drug-dependence disorder, which is more serious than a drug-abuse disorder, is diagnosed when drug use in the past twelve months has reached the level of abuse and meets at least three of seven criteria that include tolerance (increasing amounts of the drug must be taken to achieve desired effects), physical withdrawal (symptoms that accompany the cessation of drug use, such as tremors, chills, drug craving, restlessness, bone and muscle pain, sweating, and vomiting), and persistent failure to reduce drug consumption.
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Prevalence of Substance-Use Disorders (Forensic Science)
The annual National Survey on Drug Use and Health assesses the prevalence of substance-use disorders in the United States in the preceding twelve months. In 2005, the findings of this survey indicated that an estimated 22 million persons aged twelve and older were classified with a substance-abuse or -dependence problem (9 percent of the U.S. population). Among these individuals, more than 3 million were classified with abuse of or dependence on both alcohol and illicit drugs, more than 3.5 million abused or were dependent on illicit drugs but not alcohol, and more than 15 million abused or were dependent on alcohol but not illicit drugs.
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Further Reading (Forensic Science)
Abadinsky, Howard. Drug Use and Abuse: A Comprehensive Introduction. 6th ed. Belmont, Calif.: Thomson/Wadsworth, 2008. Covers all aspects of drug and alcohol abuse, including the history of drugs and their pharmacological effects. Also discusses the impacts of drug abuse on society.
Hoffman, John, and Susan Froemke, eds. Addiction: Why Can’t They Just Stop? New York: Rodale, 2007. Companion volume to a television series of the same name presents detailed descriptions of the effects of drugs on the brain, drug treatment methods, and recovery. Features many engaging case studies and sidebars.
Karch, Steven B., ed. Drug Abuse Handbook. 2d ed. Boca Raton, Fla.: CRC Press, 2007. Provides a compendium of authoritative information on various aspects of drug abuse. Contributing authors include medical, legal, and treatment professionals.
National Institute on Drug Abuse. Drugs, Brains, and Behavior. Washington, D.C.: National Institutes of Health, 2007. Brief, highly readable document explains the science of addiction in nontechnical terms.
Substance Abuse and Mental Health Services Administration. Results of the 2005 National Survey on Drug Use and Health: National Findings. Washington, D.C.: Author, 2006. Presents the findings of an annual survey on drug use conducted by the U.S. Department of Health and Human Services with a sample of the general population of the...
(The entire section is 236 words.)