To update clinicians on the latest in evidence-based treatments for substance use disorders (SUD) and non-substance use disorders among adults and suggest how these treatments can be combined into an evidence-based process that enhances treatment effectiveness in comorbid patients.

Articles were extracted from Pubmed using the search terms “dual diagnosis,” “comorbidity” and “co-occurring” and were reviewed for evidence of effectiveness for pharmacologic and psychotherapeutic treatments of comorbidity.

Twenty-four research reviews and 43 research trials were reviewed. The preponderance of the evidence suggests that antidepressants prescribed to improve substance-related symptoms among patients with mood and anxiety disorders are either not highly effective or involve risk due to high side-effect profiles or toxicity. Second generation antipsychotics are more effective for treatment of schizophrenia and comorbid substance abuse and current evidence suggests clozapine, olanzapine and risperidone are among the best. Clozapine appears to be the most effective of the antipsychotics for reducing alcohol, cocaine and cannabis abuse among patients with schizophrenia. Motivational interviewing has robust support as a highly effective psychotherapy for establishing a therapeutic alliance. This finding is critical since retention in treatment is essential for maintaining effectiveness. Highly structured therapy programs that integrate intensive outpatient treatments, case management services and behavioral therapies such as Contingency Management (CM) are most effective for treatment of severe comorbid conditions.

Creative combinations of psychotherapies, behavioral and pharmacological interventions offer the most effective treatment for comorbidity. Intensity of treatment must be increased for severe comorbid conditions such as the schizophrenia/cannabis dependence comorbidity due to the limitations of pharmacological treatments.