A 21-year-old man presents to the Emergency Department with a 6-month history of unusual behavior.

Comprehensive and Detailed Explanation:

The patient presents with classic symptoms of schizophrenia: delusions, hallucinations, social withdrawal, and disorganized appearance. The first-line treatment is antipsychotic medication—risperidone is a well-tolerated option among second-generation antipsychotics.

Toronto Notes 2023 – Psychiatry, “Schizophrenia”:

“Schizophrenia is treated with second-generation antipsychotics such as risperidone. These reduce positive symptoms like delusions and hallucinations.”

MCCQE1 Objectives (Psychiatry > 71-3: Psychotic Disorders):

“Candidates must recognize and manage schizophrenia with antipsychotics and distinguish from other mood or personality disorders.”

CBT (E) is supportive but not first-line. ECT (A) is used for severe depression or catatonia. Valproic acid (C) and carbamazepine (D) are mood stabilizers, not first-line for schizophrenia.

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