Antipsychotic Drug Treatment of Schizophrenic Patients with Substance Abuse Disorders

Abstract

Background/Aim: In recent years, there has been a growing interest in developing adequate treatments for patients with a diagnosis of schizophrenia and a comorbid substance use disorder (SUD). In the present paper we aim to critically review published reports on the use of conventional and second-generation antipsychotics in the treatment of patients with schizophrenia and comorbid SUD, to provide clinicians with a clearer view of the pharmacological treatment of this highly prevalent dual diagnosis based upon the evidence arising from the scientific literature. Methods: A search of the relevant literature from Medline, PsycLIT and EMBASE databases, included in the Science Citation Index, and available up to November 2006 was conducted using the terms: ‘schizophrenia’, ‘substance use disorder’ and ‘antipsychotics’. Results: While research on the use of conventional antipsychotics has remained limited, the majority of studies suggest the effectiveness of second-generation antipsychotics, particularly clozapine, for patients with schizophrenia and a comorbid substance use disorder. Conclusion: In the absence of randomized controlled trials that could provide more reliable information, clinical decisions may need to rely on indirect data provided by the increasing number of case reports, open trials and retrospective studies showing a decrease in cigarette smoking, alcohol, cocaine or cannabis use and an improvement of overall psychiatric symptoms.

Treatment of substance abusing patients with comorbid psychiatric disorders

“…Emergency department studies find that cannabis is the drug most often associated with exacerbations of schizophrenia and acute psychotic episodes and cannabis use contributes to poor treatment outcomes for psychotic patients (Latt et al, 2011; Moore et al, 2007). The atypical antipsychotic clozapine has been found to be the most effective medication in reducing alcohol and cannabis use (Green et al, 2003; Lybrand & Caroff, 2009; San et al, 2007), while findings on other medications are equivocal. Baker and colleagues' (2010) review suggests that using antipsychotics may be helpful in reducing cannabis use but studies that have found improvement have used active psychotherapies, thereby obscuring the degree of benefit from pharmacotherapy.…”

Protocols of Dual Diagnosis Intervention in Schizophrenia

“…In contrast, second-generation antipsychotics could have a greater effect, improving the defectual symptoms and decreasing the craving. 87 There are also studies on first and second-generation antipsychotics used as intramuscular formulations.…”

The World Federation of Societies of Biological Psychiatry (WFSBP) Guidelines for the Biological Treatment of Substance Use and Related Disorders. Part 2: Opioid dependence

“…Although patients with schizophrenia have a four-fold risk of substance use disorders, few studies have been conducted in patients with the comorbid conditions (for a review see San et al 2007;Wobrock and Soyka 2008). Treatment with antipsychotics may be necessary and is safe in most patients, but pharmacological interventions that are specifi c for substance dependence must be kept in mind (Eap et al 2002;McKane-Katz et al 2010).…”

“…Treatment with antipsychotics may be necessary and is safe in most patients, but pharmacological interventions that are specifi c for substance dependence must be kept in mind (Eap et al 2002;McKane-Katz et al 2010). Despite the absence of randomized controlled trials, treatment with secondgeneration antipsychotics can generally be safely recommended (San et al 2007;Wobrock and Soyka 2008). There is limited evidence for clozapine to reduce craving in patients with comorbid substance use disorders and schizophrenia (Drake et al 2000;Brunette et al 2006;Green et al 2003Green et al , 2008.…”