addiction

State of dependence caused by frequent and regular use of drugs, alcohol, or other substances. It is characterized by uncontrolled craving, tolerance, and symptoms of withdrawal when access is denied. Habitual use produces changes in body chemistry and treatment must be geared to a gradual reduction in dosage.

The meaning of ‘addiction’ is complicated and depends partly on the drug to which is being referred. Typical addictive drugs are alcohol, nicotine (in cigarette smoke), cocaine (including crack), heroin, amphetamines, and barbiturates.

It is thought that there are three stages to an addiction. In the first stage the dose of the drug has to be continually increased in order to get the same effect. This is called tolerance. The second stage is when the person is dependent on the drug and feels depressed or ill if they do not take it. In the third stage, the person has a compulsion to seek out the drug and this drug-seeking becomes a dominant part of their lives.

Dependence Dependence on a drug can be very different from one drug to another. The most dangerously addictive drugs result in a physical addiction. Cocaine and heroin are examples of this kind of drug. A cocaine addict who does not get a dose of the drug becomes agitated, confused, fatigued, emotionally depressed, and acutely anxious; experiences physical effects, such as irregular heartbeat and oversensitivity to pain; and has a desperate urge to take the drug again. For other drugs, such as alcohol, withdrawal does not produce such severe effects.

Drug-seeking behaviour Drug-seeking behaviour is perhaps the least understood part of the process of addiction. We do not know the extent to which this is driven by chemical processes in the body, thought processes in the mind, or the social influence of the people in contact with the addict. However, there is no doubt that drug-seeking behaviour and mood changes destroy the lives of addicts.

Addictive drugs Initially, only opium and its derivatives (morphine, heroin, codeine) were recognized as addictive. However, many drugs, whether therapeutic (for example, tranquillizers) or recreational (such as cocaine and alcohol), are now also known to be addictive.

Causes of addiction Some research has indicated a genetic predisposition to addiction, although the results are inconclusive and contentious. Environmental effects and psychological make-up are other factors. Although physical addiction always has a psychological element, not all psychological dependence is accompanied by physical dependence. A carefully controlled withdrawal programme can reverse the chemical changes of habituation. Cure is difficult because of the many factors contributing to addiction.