A conceptual framework for explaining drug addiction.

The aim of this paper is to describe a conceptual framework of questions which an adequate theory of drug addiction must attempt to answer. First, a satisfactory definition of addiction is sought and it is concluded that it is best defined by repeated failures to refrain from drug use despite prior resolutions to do so. This definition is consistent with views of addiction that see decision-making, ambivalence and conflict as central features of the addict's behaviour and experience. On this basis, a three-level framework of required explanation is set out, consisting of (1) the level of neuroadaptation, (2) the level of desire for drugs and (3) the level of 'akrasia'or failures of resolve. The crucial argument is made that explanatory concepts used at the'lower' levels in this framework can never be held to be sufficient as explanations at higher levels, i.e. the postulation of additional determinants is always required at Levels 2 and 3. In particular, it is a failure to address problems at the highest level in the framework that marks the inadequacy of most existing theories of addiction. The paper concludes by considering the relevance of the ideas presented to the concept of 'compulsive drug use' and concludes that this concept is no longer useful in the explanation of addiction.