Abstract Introduction Neuroleptic Malignant Syndrome (NMS) is a rare but potentially life-threatening complication of antipsychotic use, characterized by fever, autonomic dysfunction, altered mental status, and neuromuscular abnormalities. It occurs in approximately 0.02% to 3% of patients receiving antipsychotic medications, with first-generation neuroleptics, such as haloperidol, carrying a higher risk. Although NMS remains uncommon, early recognition is critical as it is associated with significant morbidity and mortality if untreated. The mainstay of management involves immediate discontinuation of the offending agent, aggressive supportive care, and targeted pharmacologic therapy. This case highlights the importance of early recognition and a multidisciplinary approach in managing NMS to prevent severe complications and prolonged hospitalization. Case Description A 24-year-old male with a history of major depressive disorder, cannabis use disorder, and substance-induced mood disorder was admitted to the psychiatric unit due to aggressive behavior and medication noncompliance. During hospitalization, he received multiple doses of oral and intravenous haloperidol for agitation. Subsequently, a rapid response was activated due to a sudden decline in mental status, accompanied by diaphoresis, hyperthermia, hyperreflexia, muscle rigidity, and myoclonus. Given concerns for NMS, the patient was transferred to the medical intensive care unit for further management. Neurology and toxicology were consulted. A CT head, brain MRI, lumbar puncture, and EEG were performed, all of which were non-contributory. The patient was initially treated with phenobarbital and a clonidine taper for persistent dysautonomia. Given ongoing autonomic instability and muscular rigidity, bromocriptine was initiated and gradually tapered over an extended period, leading to a gradual resolution of symptoms. Following clinical improvement, the patient was transferred back to the psychiatric unit for further stabilization and was ultimately discharged after a 50-day hospitalization. Discussion NMS is a rare but serious condition associated with antipsychotic use. This case highlights key clinical features of NMS, including autonomic instability, hyperthermia, muscle rigidity, and altered mental status, which can mimic other neurological and systemic conditions. The extensive diagnostic workup, including neuroimaging, lumbar puncture, and EEG, was essential in ruling out alternative causes, reinforcing the importance of a high index of suspicion for NMS in patients receiving neuroleptic medications. Given the association between first-generation antipsychotics and increased NMS risk, clinicians should remain vigilant, particularly in patients with multiple psychiatric comorbidities. A multidisciplinary strategy, along with tailored pharmacologic and supportive care, is crucial for optimizing patient outcomes. Further research into risk stratification and alternative management strategies would improve early diagnosis and treatment efficacy for NMS. This abstract is funded by: None
Sedaghati et al. (Fri,) studied this question.