[Dual diagnosis of psychosis and addiction. From principles to practice]

The prevalence of comorbidity of psychosis and substance abuse/addiction has been on the rise during the last 10-20 years. Meanwhile, dual diagnosis patients (DD patients) represent a large core group among patients with schizophrenia, and they are difficult to treat. Biological, psychological, and social factors may account for the comorbidity, and the single factors may interact with each other. DD patients tend to have poor compliance and unfavorable outcomes with frequent psychotic relapses and hospitalizations. Efficient treatment models integrate traditional psychiatric therapy and therapy of addiction and modify or adjust the two components to each other. The most successful programs offer integrated treatment for both disorders in one setting. These programs focus on outpatient treatment, they offer pharmacotherapy, motivation therapy, psychoeducation, cognitive-behavioral therapy, and family interventions, and they can achieve significant improvements of social adjustment and decreases of substance use.