Successful management of delirium with dexmedetomidine in a patient with haloperidol-induced neuroleptic malignant syndrome: A case report

Abstract

BACKGROUND

We report a case of lorazepam-induced agitated delirium treated with haloperidol, which in turn triggered the onset of neuroleptic malignant syndrome (NMS). The latter condition, a medical emergency, was effectively treated with medical treatment and dexmedetomidine, a versatile and highly selective short-acting alpha-2 adrenergic agonist with sedative-hypnotic and anxiolytic effects.

CASE SUMMARY

A 65-year-old man with a history of bipolar disorder presented to the emergency department with severe abdominal discomfort after binge eating. During his hospital stay, he received intravenous lorazepam for insomnia. On the next day, he became delirious and was thus treated with seven doses (5 mg each) of haloperidol over a 48 h period. Signs of NMS (hyperthermia, rigidity, myoclonus of upper limbs, impaired consciousness, tachypnea, and dark urine) became apparent and haloperidol was immediately suspended and brisk diuresis was initiated. On intensive care unit admission, he was confused, disoriented, and markedly agitated. Dexmedetomidine infusion was started with the goal of achieving a Richmond Agitation-Sedation Scale score of -1 or 0. NMS was resolved gradually and the patient stabilized, permitting discontinuation of dexmedetomidine after 3 d.

CONCLUSION

Dexmedetomidine may be clinically helpful for the management of NMS, most likely because of its sympatholytic activity.

Keywords: Haloperidol; Dexmedetomidine; Delirium; Neuroleptic malignant syndrome; Alpha-2 adrenergic agonists; Case report

Core Tip: Neuroleptic malignant syndrome (NMS), a life-threatening condition characterized by hyperthermia, rigidity, altered mental status, and dysautonomia, can occur in 0.02%–3% of patients who receive haloperidol. Herein, we report a case of lorazepam-induced agitated delirium treated with haloperidol, which further triggered NMS. The NMS was effectively managed with medical therapy and dexmedetomidine, a versatile and highly selective short-acting alpha-2 adrenergic agonist with sedative-hypnotic and anxiolytic effects. Dexmedetomidine may be clinically helpful for the management of NMS because of its sympatholytic activity. In the presence of rapid shallow breathing, dexmedetomidine may provide better patient comfort with less respiratory depression than does propofol.