Experimental and Clinical Aspects of Drug Dependence

Abstract

Dependence disorders defy easy classification and definition, and drug abuse can be regarded as inappropriate and repetitive self-administration of inessential psychoactive substances. This description seems innocuous enough, yet there is ample room for disagreement over the interpretation of adjectives such as “inappropriate,” “repetitive,” “inessential,” and “psychoactive.” Nevertheless, it is as well to confine discussions of the concepts of abuse and dependence within broad but identifiable limits, since arguments about “what really is dependence” tend to drift into considerations of newspapers, television, sex, suspender-belts, religion, and, of course, parents. There is considerable confusion over whether the definition of drug abuse is based on some form of statistical deviation from the norm, or whether the criterion should be “all or none.” A single illicit experience with heroin can be contrasted with an occasional drink, but many former alcoholics would regard even a single lapse as abuse. The search for common underlying “defects” in the histories, environments, personalities, and physiological characteristics of dependent subjects has met with little success, and there do not seem to be good grounds for treating the many types and forms of drug dependence as a unitary disorder. No absolute criteria can be specified, and distinctions between use and abuse depend on the drug, the subject, the context in which they interact, and also the characteristics of the observer.