Psychiatric Comorbidity of Cannabis Use Disorder

  • David A. Gorelick


Objective: This chapter reviews the epidemiology and treatment of cannabis use disorder (CUD) with psychiatric comorbidity.

Methods: We summarize the findings of English-language epidemiological studies reporting current (past-year) comorbidity and of controlled clinical trials of treatment in which the majority of participants had diagnosed CUD and a specific comorbid disorder.

Results: There is substantial CUD comorbidity among community-dwelling adults with major psychiatric disorders: 4–6% for depression, 14% for bipolar disorder, 5% for anxiety disorder, and 16% for schizophrenia. Conversely, there is substantial psychiatric comorbidity among community-dwelling adults with CUD: 18–32% for depression, 8–9% for bipolar disorder, and 23–40% for anxiety disorder. No treatment is proven effective for CUD comorbidity; small-scale trials suggest that combined motivational enhancement therapy/cognitive behavioral therapy focused on both CUD and the psychiatric disorder may be effective. Single, small-scale trials suggest that lithium may be effective for comorbid bipolar disorder and clozapine for comorbid schizophrenia.

Conclusions: CUD with comorbid psychiatric disorders is common, and some behavioral interventions appear efficacious; however, there are no proven effective pharmacological treatments for this disorder.


Cannabis use disorder Cannabis Marijuana Comorbidity Schizophrenia Depression Bipolar disorder Anxiety disorder Personality disorder Treatment 


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Authors and Affiliations

  1. 1.Department of PsychiatryUniversity of Maryland School of MedicineBaltimoreUSA

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