Adolescent with Cannabis Use Disorder and Comorbid Depression
A 16-year-old boy is brought by his parents due to declining school performance, social withdrawal, and frequent marijuana use. He admits to using cannabis daily for the past year, starting before school and using throughout the day. He has stopped participating in sports and has few friends. He reports feeling sad and hopeless most days for the past 6 months but denies suicidal ideation. He has no history of trauma or other substance use. His parents are concerned and want him to stop. He is ambivalent about quitting. He has been seen by a school counselor but not by a mental health professional. His physical exam is unremarkable.
1. What is your approach to assessing and addressing his cannabis use and depressive symptoms?
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Use a confidential, non-judgmental approach. Screen for cannabis use disorder using DSM-5 criteria; he likely meets criteria for moderate to severe CUD. Screen for depression with a validated tool (e.g., PHQ-9 modified for adolescents). Assess for suicidal ideation and safety. Provide psychoeducation about the bidirectional relationship between cannabis and depression. Use motivational interviewing to explore his ambivalence and build rapport. Recommend abstinence from cannabis and offer behavioral interventions such as cognitive behavioral therapy (CBT) and motivational enhancement therapy (MET). Consider family therapy to improve communication and support. If depression persists after 2-4 weeks of abstinence, consider psychiatric evaluation for possible antidepressant treatment. Engage the parents in a supportive role without being punitive. Arrange follow-up and consider referral to adolescent substance use treatment.
2. His parents ask about medication for his depression. How do you respond?
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Explain that his depressive symptoms may be partly substance-induced and that abstinence is the first step. Medications like SSRIs are not first-line for adolescent depression unless moderate to severe and unresponsive to psychotherapy. If after a period of abstinence (e.g., 4-6 weeks) he still meets criteria for major depressive disorder, consider evaluation by a child and adolescent psychiatrist for an SSRI (e.g., fluoxetine or escitalopram) with close monitoring for suicidality. Emphasize that medication alone is not a substitute for addressing substance use. Discuss the importance of therapy and family support. Address any concerns about confidentiality and consent for treatment.