Antipsychotics

A 38-year-old man with schizophrenia has been on risperidone 6 mg/day for 2 years. He presents with complaints of galactorrhea, amenorrhea in his wife (who is also on psychiatric treatment), and erectile dysfunction. You suspect antipsychotic-induced hyperprolactinemia. Which investigation is most appropriate to confirm the diagnosis?

A 32-year-old man with schizophrenia has been on antipsychotic therapy for 6 months. He now presents with involuntary orofacial movements, tongue protrusion, and choreiform limb movements. Which is the most common antipsychotic-induced movement disorder he is experiencing?

A 38-year-old man with schizophrenia has been on risperidone 6 mg/day for 2 years with good symptom control. He now presents with tremor, rigidity, and hyperthermia (38.5°C). His creatine kinase is 1200 U/L, and serum creatinine is 1.8 mg/dL (baseline 0.9 mg/dL). What is the most appropriate immediate next step?

Which feature best distinguishes typical antipsychotics from atypical antipsychotics in terms of their neurochemical receptor profile?

A 32-year-old man with schizophrenia is started on haloperidol 10 mg daily. After 3 weeks, he develops severe akathisia and oculogyric crisis. His psychiatrist switches him to olanzapine 10 mg daily. Which pharmacological feature of olanzapine best explains the resolution of his extrapyramidal side effects?