Degree Name

Master of Science

Department or Program

Rehabilitation Counseling


Flowers, Carl R.


Individuals with co-occurring mental illness and substance use disorder (SUD) encounter a number of challenges that significantly diminish their quality of life. As compared to persons with either a mental illness or SUD alone, those with co-occurring disorders often have significantly more impairment in functioning, more severe symptoms, and are at an increased risk of health problems, hospitalization, incarceration, and suicide, amongst other negative consequences. Furthermore, those with co-occurring disorders are often more difficult to engage and retain in treatment, and have a worse prognosis than those with a single disorder. Treatment facilities are often not equipped with adequate assessment instruments for detecting co-occurring disorders and clinicians may not be sufficiently trained to treat both disorders. This review examines the impact of co-occurring disorders for individuals with a dual diagnosis, as well as treatment approaches and interventions that have been researched and demonstrated efficacy in the treatment of persons with co-occurring disorders. Therapeutic approaches such as Cognitive Behavioral Therapy (CBT), Motivational Interviewing (MI), Contingency Management (CM), and Family Psychoeducation are discussed, as well as other interventions such as case management services, vocational services, and pharmacotherapy.