The ‘junkie’ taking a ‘fix’ in a squalid room, with heroin and syringe; the alcoholic lying dead-drunk on a park bench surrounded by empty bottles which once contained cheap wine; the chain-smoker who keeps extra packets of cigarettes in the house just in case supplies run out when the shops are shut – these are our characteristic or stereotyped images of addiction. They convey the idea that drug use – or abuse – is compulsive; that the habit of using drugs has taken over the personality; and that a high price has been paid in terms of the normal priorities of life. Yet these extreme descriptions do not apply to all addicts, many of whom spend much of their time leading what most people would regard as ‘normal’ lives.
What is addiction?
Although images of drug addiction are readily available, a scientific definition is not. The term ‘addiction’ has never been precisely defined. Many medical authorities, including the World Health Organization (WHO), prefer to think not in terms of addiction but of ‘dependence’. Drug dependence can be considered as having either a psychological or a physical origin. Psychological dependence occurs when a drug pro-duces both pleasure and the strong motivation to keep on repeating the pleasurable experience. If a regular user finds that the absence of a drug causes symptoms such as sweating, shaking, nausea or even headaches, the drug is said to have established in the user a state of physical dependence. The collection of symptoms are referred to as a drug withdrawal, or abstinence, syndrome.
These definitions sound straightforward enough but the distinction between psychological and physical dependence is in fact very blurred. Cannabis, for example, is a drug known to produce pleasure, and many people who experience that pleasure want to experience it again. Some, therefore, become regular users of the drug and it is difficult to persuade them to stop, even if the use of cannabis is illegal and the penalties include imprisonment. So the drug obviously produces psychological dependence, if only in some of its users.
If someone used to taking cannabis is prevented from getting supplies, he or she does not experience tre-mors, vomiting or other obvious symptoms of with-drawal or abstinence. The drug is therefore considered as free from the risk of physical dependence. Nevertheless, the person may want the drug again so much that he (or she) feels really depressed and irritable without it. He may describe his wish to take the drug as a ‘craving’, a feeling so strong that it is almost a bodily sensation rather than a mental state. In practice, therefore, the distinction between physical and psychological dependence is often very unclear; and many people continue to use the term addiction, even if they are professionally involved in the problems of drug abuse.
Man is in many ways a creature of habit. Some of his habits are pharmacological: they involve taking drugs which affect the mind. Because these habits are often also social (such as smoking and drinking) and because they involve the hands and mouth, certain types of drug-inspired behaviour stand out against other forms of habitual activity. It would be wrong, however, to think that drug addiction can be set totally apart from other compulsive routines. Consequently, it is now quite common to find the concept of addiction used to explain patterns of re-peated behaviour that have nothing to do with the taking of drugs. People talk in general, but imprecise, terms of television addicts, workaholics, and children who are addicted to playing Space Invaders or similar video games. Compulsive gamblers have long been seen as addicts; so too are people who are never happy unless they have food in their mouths; love has been described as the most powerful form of addiction – that to a person.
The original concept of addiction centred on the class of drugs called narcotics: opium, obtained from the juice of the opium poppy, and its purified and more powerful forms such as heroin and morphine. The presence of withdrawal has already been mentioned as a characteristic of addictive drugs. The withdrawal phenomenon is linked to another characteristic fea-ture: the development of tolerance, which means that increasingly large doses of the drug are required to obtain the same effect. A dose that would be lethal for an inexperienced user can be tolerated, apparently without harm, by the habitual user. The body seeks to maintain an internal balance, a process called homeostasis. This is evident in cases of disease, when the body attempts to fight off illness, but also occurs when the body is put into an abnormal state through the use of drugs. Tolerance occurs as the body develops ways of counteracting the drugs’ chemical effects. With drugs such as the opiates, which depress the brain’s activity, compensation takes the form of an increase in the brain mechanisms that produce a feeling of excitement. The first dose of a depressant drug, therefore, produces a marked fall in brain activity, but if the same amount is given again the effects are less intense. This process of increasing tolerance develops until the original dose of the drug has hardly any effect. If, however, the drug is suddenly withdrawn, the body mechanisms designed to counterbalance its effects are still there, so there is a rebound increase in brain activity. Exactly the reverse occurs with a stimulant drug such as amphetamine: the original effect is an increase in brain activity and the withdrawal pheno-menon is depression. The concepts of tolerance and withdrawal were developed to account for the ex-periences people have with addictive drugs. However, the need to have ever-increasing amounts of a sub-stance or activity in order to experience the same psychological or physical effect is not confined to drugs. Gamblers need to raise the stakes or increase the element of risk to obtain the same thrill, moun-taineers need to climb ever higher peaks, joggers to run longer distances, motorcyclists to have ever faster machines and stamp collectors to acquire rarer spe-cimens. This seems to be the same phenomenon of tolerance, leading to the same kind of escalation of ‘dosage’ as is often found in drug use. Physical or mental states similar to drug withdrawal can also be found when habits unrelated to drugs are suddenly broken. A workaholic feels totally ‘lost’ if he can no longer go to the office. A gambler ‘itches’ to have another bet, while someone in love is irritable and depressed, and may even become physically ill, when he or she cannot be with the loved one.
Causes of addiction
Because of the range of different behaviours that can be thought of as addictive, researchers now talk not of drugs addicting people but of people addicting them-selves. Addictions are seen not as a unique kind of behaviour but as habits taken to extreme – to the extreme of being unbreakable.
This new emphasis is valuable in drawing attention to factors in the individual and the environment that increase the likelihood of addiction of any kind. There is talk of the interaction between ‘the environment, the soil, and the seed’. The drug, or other object of addiction, is the seed but it needs the right conditions of environment and soil in which to grow. The importance of the environment is shown by a famous study of American soldiers who fought in Vietnam. Before going to Vietnam only two per cent had ever used heroin, but a third admitted using it while there, and half the users said they were addicted. Yet ten months after they returned to the United States, fewer than one per cent were still daily users of narcotics. In the appalling conditions of war, heroin, given its easy availability, was an inevitable route of escape. Once the war was over, it proved relatively easy to give up.
What of the ‘soil’, the individual’s character and constitution? Scientists are only just beginning to understand what has been termed the ‘addictive personality’. It does seem that people who are addicted in many different ways nonetheless have certain things in common. One is an inability to come to terms with reality; others include behavioural characteristics such as depression and a tendency to act on impulse. These aspects of personality can be shown to exist before the person becomes an addict, so they can probably be regarded as part of the cause, not just an effect, of compulsive drug use.
Research into the personalities of addicts complements investigations into the processes going on in the brain. One of the most interesting developments in the understanding of addiction took place in the mid-1970s, when researchers discovered that there are naturally occurring substances in the brain (termed endorphins and encephalins) which are similar in chemical structure to opiate drugs. This explains why people are so sensitive to the products of the poppy: by a coincidence of chemistry, the brain is already tuned to be receptive to them. It now seems that endorphins and encephalins may help explain addiction in general and not just dependence on opiates. Drugs which block the effects of opiates have also been shown to reduce consumption of alcohol in animals and of cigarettes in smokers. There is evidence too that strains of rats and mice that suffer from a tendency to overeat, and so become obese, have abnormally high levels of the brain’s own opiate substances. If we view the habits that lead to addiction as attempts (in their different ways) to achieve pleasure, it may not be surprising that opiates, which are the substances known to provide the most intense pleasure, should somehow be involved in all of them.
Treatment of addiction
The involvement of opiatelike chemicals suggests new ways of treating certain forms of addiction. It is known that the opiate-blocking drug naloxone can prevent the euphoria normally experienced following injection of substances such as heroin into the bloodstream. If the rewards accompanying drug use can be prevented in this way, the habit of using drugs should become weaker.
A similar approach may be applicable to alcohol abuse, although the usual treatment involves not blocking the intoxication caused by alcohol, but linking the drug with some very unpleasant sensation such as nausea. This effect is obtained by treating the patient with a chemical that interacts with alcohol to produce vomiting.
In the case of cigarette smoking, pharmacological, or drug-based, therapy involves use of a nicotine chewing-gum that replaces tobacco as the usual source of the drug. The detailed approach is different from that used to treat alcohol abuse, but the theory behind thetreatment is similar: break the association between the drug behaviour and its usual reward, and the habit should eventually disappear. These drug-based, pharmacological treatments are only one approach to addiction and they leave the underlying causes untouched. Many workers involved in the rehabilitation of drug addicts argue that the problems will remain until the personality and atti-tudes of the addict are changed (this will usually require some form of psychotherapy), and until social conditions that encourage addiction are improved.