Which approach best assesses substance use disorders in individuals with schizophrenia?

• A. Screen for alcohol, cannabis, stimulants, and other substances using validated tools; assess impact on symptoms and treatment adherence
• B. Rely on patient denial
• C. Only ask about alcohol
• D. Diagnose substance use based on observation alone

Answer: (A)

Systematic screening with validated tools for multiple substances and assessing how use affects schizophrenia symptoms and treatment adherence is best. In people with schizophrenia, co-occurring substance use is common and can worsen psychotic symptoms, lead to more frequent relapses, and interfere with antipsychotic adherence and overall functioning. Using validated instruments for a range of substances—rather than focusing on a single substance or relying on subjective impressions—helps quantify severity, identify patterns, and inform integrated treatment planning. This approach also directly addresses how substance use interacts with psychiatric symptoms and adherence, which is crucial for effective management. Relying on denial, only asking about one substance, or making diagnoses based on observation alone miss many cases and fail to capture the impact on treatment outcomes.