A 45-year-old woman with a history of schizophrenia, recently initiated on a new antipsychotic medication for persistent auditory hallucinations, presents to her outpatient psychiatric clinic with her daughter. Over the past week, she has become increasingly restless and agitated, often pacing continuously around the home and expressing an overwhelming urge to move. Her daughter notes that the patient becomes distressed and irritable if attempts are made to encourage her to sit still. Despite the dose escalation of her antipsychotic, her agitation has worsened, and there is no clear change in her underlying psychotic symptoms. She denies any new focal weakness, numbness, or difficulty speaking. On examination, she constantly shifts in her seat and taps her feet but exhibits no overt abnormal involuntary movements. Her vital signs are stable: temperature 36.8°C, blood pressure 128/78 mmHg, respiratory rate 16/min, and pulse 88/min. Which of the following is the most appropriate initial management strategy, and what is a potential severe long-term complication if this condition is left untreated?