The mystery of addiction
Authors: David F Musto
Journal: The Lancet (1999)

David F Musto trained at the University of Washington, Seattle, and Yale University. He is professor of child psychiatry and the history of medicine at Yale University. The third edition of his book The American Disease: Origins of Narcotic Control has been published by Oxford University Press. In Roman law an addictus was a debtor turned over to his creditor to serve as a bondman or servant. Unlike a slave, the addictus could be released when his debt had been paid (which would suggest some therapeutic optimism if applied to a drug user). Over the past millennium the concept of addiction has evolved. Although currently the term addiction is used to describe widely varying degrees of seriousness, the core sense is usually an inability to control one's use of some activity such as drug taking, even when the addict agrees that it is destructive. The fascinating mystery of addiction—that the spirit is willing but the flesh is weak—has led to ingenious, persistent, and colossal efforts to separate the addict from the addictive behaviour. Addiction has been increasingly linked to habit-forming substances that are the product of chemical technology. The earliest example, distilled spirits, had been made possible through the distillation apparatus, probably introduced into Europe from Arabia in the 12th century. Production of nearly pure alcohol followed, but in very small amounts. Informed opinion held that alcohol preserved the body since studies showed that meat left in an alcohol solution did not rot compared with the control meat placed in water. As long as distilled spirits were scarce, their use caused few difficulties. Around the 16th century, however, production rose substantially and so did related problems. The availability of a cheap beverage that was four or more times as powerful as traditional beer or wine raised a dilemma for society that struggled to adjust to the impact of high-alcohol content drinks. Violence, low productivity, disrupted families, and sickness countered claims of health traditionally ascribed to distilled spirits. That distilled spirits had the power to addict seemed certain to alarmed observers. Others argued that the imbiber was taking the healthier course by drinking until drunk. A dramatic clash between these two views extended the duration of the London gin epidemic over the first half of the 18th century. To this day, large populations still maintain that alcohol is a healthy tonic, even when taken to intoxication, whereas others condemn alcohol as a poison that can only harm the user. Internationally, opium and its derivatives have rivalled alcohol as a source of concern and addictive liability. From its original habitat, the Anatolian Highlands, the cultivation of the opium poppy has been extended in a profuse band that extends to the Golden Triangle of southeast Asia. It is now grown in South America as well. The opium habit with its characteristic withdrawal pattern has become the model addiction. Morphine, the primary active ingredient in crude opium, had been first isolated in the first decade of the 19th century. Produced in large amounts by the 1830s, morphine offered pain relief as well as the possibility of addiction. The most successful addictive relative of opium is heroin, introduced as a cough suppressant by the Bayer Company in 1898. Cocaine, although isolated and named in 1860, was not widely used until the 1880s. At first considered a cure for an opium or morphine habit, cocaine had its own array of side-effects—paranoia, hyperstimulation, and cardiac sensitivity that offset its initial effect as an anaesthetic and euphoriant. Cocaine's potential for compulsive use meets the common-sense definition of addiction, although some investigators have denied that it is addictive because it does not follow the course of opium withdrawal. This interpretation has been confusing for the public which equates addictive with danger and non-addictive with safety. Addictive substances have increased exponentially as we end the millennium. Not only have chemists succeeded in isolating the active ingredients of crude opium and the coca leaf; more recently biochemists have created drugs that do not exist in nature but have a powerful effect on the brain. Amphetamine, methamphetamine, and Ecstasy are 20th-century stimulants; and pethidine and methadone are examples of synthetic opiates. During the past two decades we have been closing in on the biology of addiction. Past explanations for addiction extended from the "addictive personality" to the invincible impact of the drug. The belief that anyone can become addicted has alternated with the conviction that only those with a particular diathesis—physical, mental, or social—will succumb to addiction. For a thousand years addiction has been a concern, but the details of its process have been only guessed at. Contributing to an eagerly awaited explanation is the human genome project which may well explain why some people cannot control drug use. On the other hand, this hope may just reflect the trend over the past decades toward biological determinism. The mystery of addiction is so central to our existence that it probably will be solved only when the mystery of human personality is unravelled.