The Impact of Quetiapine on the Drug Abuse Patterns of Addicted Schizophrenic Patients

The Impact of Quetiapine on the Drug Abuse Patterns of Addicted Schizophrenic Patients

The lifetime of substance use disorders in schizophrenia is close to 50%. Substance abuse in schizophrenia is associated with negative consequences. Unfortunately, there no clear guidelines for the pharmacological treatment of this dual diagnosis population. Preliminary results suggest that second-generation antipsychotic drugs (mainly clozapine) may relieve drug cravings in schizophrenia. We performed a 12-week pilot study to evaluate the impact of quetiapine, a second-generation antipsychotic, on substance abuse parameters, psychiatric symptoms and side effects in patients schizophrenia and comorbid substance use disorders. Our expectation was a 20 % decrease in drug cravings from baseline to end-point.

Inclusion Criteria:

• Patients with as schizophrenia spectrum disorder
• Patients with a comorbid substance use disorder

Exclusion Criteria:

• Patients already on quetiapine or clozapine
• Patients hospitalized or acutely ill
• Total score lower than 65 on the PANSS
• Pregnancy
• Female subjects of childbearing potential without adequate contraception
• Abnormal liver function (hepatic enzymes more than 3 times the upper normal limits)
• Any clinically meaningful unstable renal, hepatic, cardiovascular, respiratory, cerebrovascular disease or other serious, progressive physical disease.