A patient has been prescribed chlorpromazine for schizophrenia. During a follow-up visit, the nurse observes the patient for signs of tardive dyskinesia. Which of the following?

Tardive dyskinesia is a serious, potentially irreversible movement disorder caused by prolonged use of dopamine receptor-blocking agents such as first-generation antipsychotics like chlorpromazine. The hallmark of tardive dyskinesia is involuntary, repetitive, purposeless movements, most notably rhythmic movements of the tongue, face, lips, and extremities. These movements often include lip smacking, tongue protrusion, grimacing, and choreiform limb movements. The proposed mechanism involves dopamine receptor supersensitivity in the nigrostriatal pathway following chronic blockade. Muscle rigidity and bradykinesia describe parkinsonian side effects caused by acute dopamine blockade in the nigrostriatal pathway, a distinct adverse effect from tardive dyskinesia that typically appears earlier in treatment. Sudden onset of confusion and agitation could describe acute drug-induced delirium or another adverse reaction but does not characterize tardive dyskinesia. Elevated blood pressure and tachycardia are more consistent with neuroleptic malignant syndrome, a rare but life-threatening reaction to antipsychotics characterized by hyperthermia, muscle rigidity, autonomic instability, and altered consciousness. Nurses must monitor patients on long-term antipsychotic therapy using standardized tools such as the Abnormal Involuntary Movement Scale to detect tardive dyskinesia early and report findings to the prescriber promptly.