A nurse in an emergency department is assessing a client who has been taking haloperidol for 3 months. The client has a temperature of 39.5* C (103.4° F), blood pressure of 150/110 mm Hg, and muscle rigidity. Which of the following complications should the nurse suspect?

A. "Gradually decrease the dose once tolerance to the effect is reached." - Gradually decreasing the dose may help mitigate daytime sedation, but it's not the most appropriate initial response. Additionally, it should be done under the guidance of a healthcare provider.

B. "Take most of the daily dose at bedtime." - This response is appropriate because diphenhydramine commonly causes drowsiness, and taking most of the dose at bedtime can help minimize daytime sedation.

C. "Take the medication with meals." - Taking diphenhydramine with meals may reduce the risk of gastrointestinal upset but is unlikely to significantly decrease daytime sedation.

D. "Distribute the doses evenly throughout the day." - This approach may not effectively minimize daytime sedation because diphenhydramine's sedative effects are prolonged and may persist throughout the day if taken at regular intervals. Taking most of the dose at bedtime is a more practical strategy.

A. Akathisia: Akathisia is characterized by restlessness and an inability to sit still. While it can be a side effect of antipsychotic medications like haloperidol, it does not present with fever, hypertension, and muscle rigidity, as described in the scenario.

B. Neuroleptic malignant syndrome (NMS): NMS is a potentially life-threatening condition associated with antipsychotic medications like haloperidol. It is characterized by hyperthermia, autonomic dysfunction (e.g., hypertension), altered mental status, and severe muscle rigidity. The client's symptoms of fever, elevated blood pressure, and muscle rigidity are consistent with NMS.

C. Tardive dyskinesia: Tardive dyskinesia is a movement disorder characterized by involuntary, repetitive movements of the face, tongue, and other body parts. It is a long-term side effect of antipsychotic medications and typically develops after prolonged use, unlike the acute onset seen in the scenario.

D. Agranulocytosis: Agranulocytosis is a rare but serious side effect of antipsychotic medications, characterized by a severe reduction in white blood cell count, leading to an increased risk of infection. The symptoms described in the scenario are not consistent with agranulocytosis.