Co-occurring Substance and Mental Health Disorders

Abstract

The terms “dual diagnosis” and “co-occurring” are used to refer to patients with both psychiatric and substance use disorders, but recent research has broadened the concept to identify patients with the presence of any two or more medical conditions as well as numerous related psychosocial conditions that derive, to varying degrees, from the medical diagnoses. Traditionally, medical care for the dually diagnosed patient has focused treatment on the individual diseases and has had unintended consequences in patients with dual diagnoses, namely, the potential for high treatment burden (e.g., polypharmacy, frequent appointments, multiple procedures) or worsening of one disease by treatment of another. Within the mental health care system, this siloing (i.e., operating in isolation) of healthcare delivery approach has led to fragmented and stymied mental health care delivery. This chapter reviews the evolution of treatment for the dually diagnosed individual and veteran from the sequential approach to parallel and finally integrated approach that affords the most benefits with the least harm.