Chemical addiction is the general description for an addiction to a substance that must be injected or ingested. Alcohol, opiates, and cocaine are the most common of these chemicals. Though each of them is addictive, they have different effects on the body.
Addiction to alcohol, for example, may be the result of heavy drinking coupled with a malfunctioning type of cell in the liver of the alcoholic. Many adults can drink large quantities of alcoholic beverages and suffer only a "hangover"—headache and nausea. The malfunctioning liver in the alcoholic, however, does not detoxify the byproducts of alcohol ingestion rapidly. The resultant accumulation of a chemical called acetaldehyde causes several symptoms, including pain, which can be relieved by the intake of more alcohol. The consumption of ever-increasing amounts of alcohol with greater frequency can lead to organ failure and death if the alcoholic is left untreated.
Opium, produced by a species of poppy, is an ancient addictive substance that is still produced for its cash value. Although raw opium is not the form most addicts encounter, purified, powdered opium has been used in many forms for hundreds of years. Tincture of opium, or laudanum, was introduced about 1500. Paregoric, a familiar household remedy today, dates from the early 1700s.
Heroin, a derivative of opium, has become a common addictive drug. Heroin is a powder dissolved in water and injected into the user's vein, giving an immediate sensation of warmth and relaxation. Physical or mental pain is relieved, and the user enters a deeply relaxed state for a few hours. The powder can also be inhaled for a milder effect. Heroin is extremely addictive and with only a few doses the user is "hooked." Morphine, a refinement of opium, was discovered in the early 1800s. It was first used as an effective analgesic, or painkiller, and it is still used for that purpose. Its fast action makes it a drug of choice to ease the pain of wounded soldiers during wartime. Morphine has one-fifth the addictive power of heroin.
Cocaine in its various forms is another class of addictive compounds. In fact, it is the most addictive of these drugs; some people need only a single exposure to the drug to become addicted. Cocaine is processed from the coca plant and is used in the form of a white powder. It can be inhaled, ingested, injected, or mixed with marijuana and smoked. It is also further processed into a solid crystalline substance marketed as "crack." Unlike the opiates, which bring on a warm feeling and immobility, cocaine makes its users energetic. This strong stimulation and period of hyperactivity (usually no more than half an hour) is quickly followed by a period of intense depression, fatigue, and paranoia. In order to relieve these harsh side effects, the user will typically retreat to taking more cocaine or using another drug, for example alcohol or heroin. Suicide is a common occurrence among cocaine addicts.
Any of these chemical substances can become the object of intense addiction. Addicts of the opiates and cocaine must have increasingly frequent doses to maintain their desired physiological effects. Soon the addict has difficulty focusing on anything else, making it nearly impossible to hold a job or maintain a normal lifestyle. These drugs are of economic importance not only because of their high cost, but also because of the crimes committed to obtain the cash necessary to buy the drugs. The drug enforcement resources dedicated to policing those crimes and the rehabilitation programs provided to the drug addicts are costly.
Some experts consider drinking large amounts of coffee or cola beverages evidence of an addiction to caffeine. In fact, these substances do provide a short-term mood lift to the user. The first cup of coffee in the morning, the midmorning coffee break, the cola at lunch, and the dinner coffee are habitual. Withdrawal from caffeine, which is a stimulant, can cause certain mood changes and a longing for additional caffeine.
Tobacco use is also addictive (due to the nicotine found in tobacco). Cigarette smoking, for example, is one of the most difficult habits to stop. Withdrawal symptoms are more pronounced in the smoker than in the coffee drinker. Reforming smokers are subject to swift mood swings and intense cravings for a cigarette. A long-time smoker may never overcome the desire for cigarettes.
Withdrawal symptoms are caused by psychological, physical, and chemical reactions in the body. As the amount of addictive chemical in the blood begins to fall, the urge to acquire the next dose is strong. The hard drugs such as heroin and cocaine produce intense withdrawal symptoms that, if not eased by another dose of the addictive substance or an appropriate medication, can leave the user in painful helplessness. Strong muscle contractions, nausea, vomiting, sweating, and pain increase in strength until it becomes extremely difficult for the user to stay away from the drug.