Abstract
The self-medication hypothesis (SMH) is an intuitively appealing explanation for substance use. Conceptually, however, it is not always clear what the hypothesis entails, particularly when applied to persons with mental and substance use disorders. This makes empirical support for SMH difficult to evaluate. By classifying the self-reported reasons for substance use from 33 participants in a NIMH-funded qualitative study of dual diagnosis and homelessness, this study aims to evaluate the applicability of SMH. How one conceptualizes SMH will determine whether SMH is empirically supported. When SMH refers to using substances strictly to cope with symptoms of mental disorders, only 11 out of 72 attributions support it. When SMH refers to using substances to cope with painful feelings in general, more than half of all attributions support SMH. The significance of accurately understanding the various reasons people give for why they use substances is discussed. (Am J Addict 2007;16:160–165)