heroin

drug
Also known as: diacetylmorphine
Also called:
diacetylmorphine

heroin, highly addictive morphine derivative that makes up a large portion of the illicit traffic in narcotics. Heroin is made by treating morphine with acetic anhydride; the resulting substance is four to eight times as potent as morphine. (Morphine is an alkaloid found in opium, which is the dried milky exudate obtained from the unripe seedpods of the poppy plant.)

Heroin was first synthesized from morphine by a British chemist in 1874 and was introduced as a commercial product by the Bayer Company of Germany in 1898; it was originally used as a narcotic analgesic, but its undesirable side effects were found to far outweigh its value as a pain-killing drug, and there are now strict prohibitions on its use in many countries. In the United States, for example, narcotics such as heroin are regulated under the Controlled Substances Act, which established a classification system with five schedules to identify drugs based on their potential for abuse, their applications in medicine, and their likelihood of producing dependence. The act is implemented by the Drug Enforcement Administration, which is empowered to prosecute violators of laws governing these controlled substances.

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Physiological effects

Heroin constricts the user’s pupils, slows respiration, heartbeat, and gastrointestinal activity, and induces sleep. Among those addicted to it, however, heroin’s most valued effect is the ecstatic reaction that it gives after being intravenously injected; within seconds a warm, glowing sensation spreads over the body. This brief but intense rush is then followed by a deep, drowsy state of relaxation and contentment that is marked by a clouding of consciousness and by poor concentration and attention. This state lasts two to four hours and then gradually wears off. Some individuals do react negatively to heroin, experiencing only anxiety, nausea, and depression.

Heroin in powder form can be sniffed, or inhaled. When dissolved in water, it can be injected subcutaneously (skin-popping) or intravenously (mainlining). But heroin addicts, as opposed to novice users of the drug, almost invariably inject it intravenously, because this produces the most rapid and intense euphoric effects.

Heroin addiction

Heroin is a highly addictive drug, and an addict must usually inject heroin about twice a day in order to avoid the discomfort of withdrawal symptoms; these include restlessness, body aches, insomnia, nausea, vomiting, and diarrhea. An addict trying to break the body’s dependence on heroin must undergo an intense withdrawal period lasting three or four days, with symptoms lessening markedly thereafter. Heroin addicts also develop a high tolerance to the drug; thus an addict must use the drug more often or in greater amounts to achieve the desired euphoric effects. Nevertheless, these effects tend to disappear completely in the case of very heavy use, although the physical addiction remains.

A heroin addiction is expensive to maintain, and such addicts, when not gainfully employed, often must find other ways to support their habit, some examples being borrowing money from friends and family under false pretenses and engaging in criminal activity, prostitution, identity theft and fraud, and drug peddling. Heroin addicts—and opioid addicts more generally—commit a disproportionately large share of crimes in countries where drug use is problematic.

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Heroin illegally available on the street is of varying purity, anywhere from 1 to 100 percent. More dilute versions of the drug are produced by mixing it with baking soda, quinine, starch, sugar, or other substances. Especially dangerous combinations include the use of rat poison or the narcotic drug fentanyl. The unwitting injection of relatively pure heroin is a major cause of heroin overdose, the main symptoms of which are extreme respiratory depression deepening into coma and then into death. Aside from this danger, heroin addicts are prone to hepatitis and other infections stemming from their use of dirty or contaminated syringes; scarring of the surfaces of the arms or legs is another common injury, because of repeated needle injections and subsequent inflammation of surface veins.

The private use and possession of heroin is illegal in most countries of the world, although the drug may be used as a painkiller for terminal cancer patients and others who suffer severe pain. Most illegally distributed heroin comes from opium produced in the Middle East, Southeast Asia, and Mexico. At the start of the 21st century, the leading opium-producing countries included Afghanistan, Myanmar (Burma), and Laos. Heroin addiction first appeared in the early 20th century, and for several decades thereafter it was customarily confined to the marginal or criminal elements in Western societies. But from the 1960s on its use spread to youths in middle- and upper-income families and to populations in less-developed regions. Heroin use and trafficking are worldwide problems, and both national and international law enforcement and regulatory agencies seek to control and suppress those activities.

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Kara Rogers.

drug abuse, the excessive, maladaptive, or addictive use of drugs for nonmedical purposes despite social, psychological, and physical problems that may arise from such use. Abused substances include such agents as anabolic steroids, which are used by some athletes to accelerate muscular development and increase strength and which can cause heart disease, liver damage, and other physical problems; and psychotropic agents, substances that affect the user’s mental state and are used to produce changes in mood, feeling, and perception. The latter category, which has a much longer history of abuse, includes opium (and such derivatives as heroin), hallucinogens, barbiturates, cocaine, amphetamines, tranquilizers, the several forms of cannabis, and alcohol. A brief treatment of drug abuse follows. For full treatment, see drug use. See also steroid.

The history of nonmedical drug consumption is ancient. The discovery of the mood-altering qualities of fermented fruits and substances such as opium has led to their use and, often, acceptance into society. Just as alcohol has a recognized social place in the West, so many other psychotropics have been accepted in different societies.

The major problem that arises from the consumption of psychotropic drugs is dependence, the compulsion to use the drug despite any deterioration in health, work, or social activities. Dependence varies from drug to drug in its extent and effect; it can be physical or psychological or both. Physical dependence becomes apparent only when the drug intake is decreased or stopped and an involuntary illness called the withdrawal (or abstinence) syndrome occurs. Drugs known to produce physical dependence are the opiates (i.e., opium and its derivatives) and central-nervous-system depressants such as barbiturates and alcohol. Psychological dependence is indicated when the user relies on a drug to produce a feeling of well-being. This type of dependence varies widely with both substance and user. In its most intense form the user becomes obsessed with the drug and focuses virtually all his interest and activity on obtaining and using it.

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Another related phenomenon is tolerance, a gradual decrease in the effect of a certain dose as the drug is repeatedly taken; increasingly larger doses are needed to produce the desired effect. Tolerance does not always develop. It is most marked with habitual opiate users. The term addiction is often used synonymously with dependence but should probably be reserved for drugs known to cause physical dependence.

Other hazards of drug abuse include general risks, such as the danger of infection by the AIDS virus and other diseases that can be communicated by use of nonsterile needles or syringes when drugs are taken by injection. Some hazards are associated with the specific effects of the particular drug—paranoia with high doses of stimulants, for example. In addition, adverse social effects stemming from drug abuse are numerous.

Heroin, an opiate that is not used medically in the United States, is one of the drugs most associated with abuse and addiction in the eyes of the public. In general, opiates are called narcotics because they are used medically to relieve pain and produce sleep. Other opiates that have been abused are opium, morphine, pethidine, codeine, dipipanone, and methadone. Methadone is often used in substitution therapy as a less-addictive opiate that, theoretically at least, can be used to wean the user off heroin and eventually off opiates altogether.

Drugs that either depress or stimulate the central nervous system have long been used for nonmedical reasons. Depressants include all sedatives and hypnotics such as barbiturates and benzodiazepines (minor tranquilizers). These are usually taken by mouth but can be injected. The main stimulants are amphetamines or their derivatives and cocaine, a natural component of the leaves of the coca plant. Amphetamines can be taken by mouth or injected; cocaine is either injected or inhaled through the nose. One form of cocaine (freebase, or crack) is generally smoked.

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Other drugs that are frequently abused include cannabis (marijuana, hashish, etc., from the hemp plant Cannabis sativa), PCP, and such hallucinogens, or psychedelics, as LSD and mescaline.

The purchase, sale, and nonmedical consumption of all the aforementioned drugs are illegal, and these psychotropic drugs can be obtained only on the black market. However, this is not the only route to drug abuse. Alcohol, for instance, can be legally purchased throughout much of the world, despite its high potential for abuse. Also, dependence on prescribed drugs is not uncommon, especially with tranquilizers and hypnotics. What was once a serious social problem of dependence on prescribed barbiturates has been overtaken largely by the widespread use of benzodiazepine tranquilizers such as diazepam (Valium), alprazolam (Xanax) and chlordiazepoxide (Librium) . Millions of legal prescriptions for these drugs are issued every year.

Problems relating to drug abuse can also occur with substances not normally thought of as drugs. Solvent abuse, commonly known as “glue-sniffing,” is a growing problem, especially among teenagers and even younger children. The inhalation of volatile solvents produces temporary euphoria but can lead to death by respiratory depression, asphyxiation, or other causes.

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Adam Augustyn.