Treatment of schizophrenia and comorbid substance use disorder.

Comorbid alcohol and substance use disorders occur commonly among patients with schizophrenia and contribute to the morbidity of schizophrenia. These comorbid disorders add greatly to the financial costs and emotional toll that schizophrenia places on patients, families and the entire mental health system. While the basis for the increased abuse of alcohol and other substances in patients with schizophrenia have been linked by some investigators to "self-medication" of negative symptoms of schizophrenia or extrapyramidal system effects of typical antipsychotics, we have presented a neurobiologic formulation suggesting that alcohol or other substances may transiently correct a dysfunction of the dopamine-mediated mesocorticolimbic pathways in patients with schizophrenia - pathways linked to brain reward circuits.