Self-medication hypothesis of substance use: testing Khantzian's updated theory.

Substance use research has been a salient focus for mental health professionals in recent years. Several organizations, including the American Psychological Association, have been pressing for more substance use research, particularly clinically relevant, theory-based investigations. However, there are few theories of substance use, and even fewer with scientific support. One theory is the Self Medication Hypothesis by Khantzian (1977, 1974), a theory with 30 years of research. However, recent modifications in Khantzian's theory (1999) have not been properly tested. Specifically, two areas require further investigation: Khantzian's belief that more negative affect should be related directly to more substance use, and expanding the number of affective states examined, including alexithymia, to better operationalize Khantzian's belief that several painful and ambiguous forms of affect may be implicated in the self-medicating process. The current study assessed anxiety, depression, hostility and alexithymia levels in 70 methadone maintenance treatment patients. Results indicated that affective measures did not have the expected relationship with reported substance use. The authors advocate for the exploration of multiple factors, not merely emotional regulation, in the variability of substance use.