The slightly modified term “co-occurring substance misuse and mental health problems” refers more specifically to the observation that these co-occurring substance use and mental issues are frequently associated with the misuse of drugs and alcohol in ways that may complicate and contribute to psychological illness. In this context, the term “substance misuse” refers to the use of illegal drugs, the illicit use of prescription drugs and/or the excessive use of alcohol. When substance misuse and mental health problems co-occur in the same individual, this is termed a “dual diagnosis” or “co-morbidity”, although it should be noted that these two terms may apply more generally to any two conditions existing simultaneously in the same individual.
The increased awareness of the co-existence of mental health and substance abuse issues in clients seeking or requiring psychological treatment represents an acknowledgement that mental health issues may have complex, multi-faceted origins that require individualized approaches to treatment and recovery (Drake & Wallach, 2000). It has also drawn attention that many individuals who are substance abusers are not simply guilty of criminal or excessive behaviours, but may abuse drugs or alcohol in the context of undiagnosed or untreated mental illness (Brems et al., 2006). The purpose of this essay is to explore some of the current assessment and therapeutic approaches to the treatment of clients presenting with this type of dual diagnosis, including cognitive behavioural therapy (CBT), motivational interviewing (MI), and brief interventions. Cognitive behavioural therapy is a therapeutic approach that is based on the premise that psychological issues are the product of aberrant thought processes and associated behaviours (Mueser et al., 2005). The goal of this approach is